257904 


A  little  fire  is  quickly  trodden  out ; 

Which,  being  suffer'd,  rivers  cannot  quench.'' 

—  SHAKESPEARE, 
Third  Part  of  Henry  VI,  Act  IF,  Scene  VIII. 


PREFACE 


IN  the  preparation  of  this  volume  it  has  been  the  author's 
aim  to  present,  in  a  manner  suitable  for  ready  reference,  the 
present  status  of  fire-resistance  as  applied  to  buildings,  including 
not  only  many  details  of  construction  which,  it  is  hoped,  will 
prove  of  practical  value  to  architects,  constructionists  and  un- 
derwriters, but  also  those  preventive  means  and  those  broad 
principles  of  scientific  fire-protective  design,  without  which  con- 
structive details  are  often  of  little  avail.  Numerous  tests  of 
materials  and  devices,  and  many  descriptions  of  past  experiences 
of  value  have  also  been  added,  in  some  detail,  for  the  benefit  of 
students  or  those  wishing  to  make  a  more  complete  study  of  the 
subject. 

In  the  past  too  much  stress  has  been  laid  upon  construction 
only,  and  fire-resistance  has  too  often  been  confounded  with 
non-combustibility.  Fire-resistance  worthy  of  the  appellation 
must  embrace,  first,  proper  planning  or  design,  which  is  the  fire- 
protective  feature  of  paramount  importance  in  theatres,  schools, 
etc.;  second,  construction;  and  last,  but  by  no  means  least, 
auxiliary  equipment  to  safeguard  both  the  construction  employed 
and  the  contents  of  the  structure.  Without  any  one  of  these 
essentials  of  fire  protection,  the  fire-resisting  qualities  of  a  build- 
ing are  questionable,  to  say  the  least. 

The  criticism  may  be  made  that  greater  stress  should  be  laid 
upon  a  better  average  of  building  construction  rather  than  upon 
high  standards  of"  detail  in  individual  units.  The  distinction 
would  be  that  a  good  average  would  tend  to  diminish  conflagra- 
tions, but,  unless  special  attention  be  paid  to  the  details  which 
often  constitute  the  crucial  weaknesses  in  case  of  fire,  separate 
buildings  would  still  be  subject  to  great  damage  and  loss  of  life. 

Many  quotations  are  given,  taken  from  reports  and  other 
sources,  in  order  to  show  the  best  present-day  opinion  of  those 
fire  protectionists  who  have  had  unusual  opportunities  for  ob- 
serving the  follies  of  past  experience.  The  author  would  grate- 
fully acknowledge  his  indebtedness  to  those  authorities,  as  well 

v 


VI  PREFACE 

as  his  obligations  to  Mr.  Edward  R.  Hardy,  of  the  New  York 
Fire  Insurance  Exchange,  for  much  help  in  connection  with 
Chapter  III,  Insurance,  —  to  Mr.  C.  H.  Blackall,  architect,  for 
criticism  and  advice  in  regard  to  Chapter  XXII,  Theatres,  — • 
to  Mr.  R.  Clipston  Sturgis,  architect,  for  criticism  and  sug- 
gestions regarding  the  planning  and  construction  of  Schools, 
Chapter  XXIII,  —  to  Mr.  Charles  T.  Main,  mill  engineer,  for 
criticism  and  assistance  in  regard  to  Factories,  Chapter  XXV,  — 
to  Mr.  L.  H.  Kunhardt,  Vice  President  and  Engineer  of  the 
Boston  Manufacturers'  Mutual  Fire  Insurance  Co.,  for  sug- 
gestions and  criticism  in  connection  with  Automatic  Sprinklers, 
especially  Chapters  XXX  and  XXXVI,  —  to  Mr.  Geo.  H. 
Bowen,  Superintendent  of  the  Boston  Automatic  Fire  Alarm 
Co.,  for  information  and  criticism  respecting  Chapter  XXXI, 
Automatic  Fire  Alarms,  —  to  Mr.  Ralph  Sweetland,  of  the  New 
England  Fire  Insurance  Exchange,  for  information  concerning 
Watchmen  and  Watch-clocks,  etc.,  in  Chapter  XXXIII,  —  to 
Mr.  R.  H.  Newbern,  Superintendent  of  the  Insurance  Depart- 
ment of  the  Pennsylvania  Railroad,  for  permission  to  quote  his 
valuable  discussion  of  Private  Fire  Departments  and  Fire  Drills 
in  Chapters  XXXV  and  XXXVII,  —  to  Mr.  John  R.  Freeman 
for  permission  to  quote  extensively  from  his  "On  the  Safeguard- 
ing of  Life  in  Theatres  "  and  to  reproduce  therefrom  his  plans  of 
a  model  theatre,  —  to  Mr.  F.  D.  Jackson,  of  the  Hecla  Iron 
Works,  Brooklyn,  N.  Y.,  for  many  photographs  of  windows, 
stairs,  elevator  enclosures,  etc.,  used  in  Chapters  XIV,  XV 
and  XVI  —  and  to  Mr.  W.  E.  Mallalieu,  General  Agent  of  the 
National  Board  of  Fire  Underwriters,  for  many  courtesies. 

J.  K.  F. 
BOSTON,  April,  1912. 


CONTENTS 


PART  I.  —  FIRE  PREVENTION  AND  FIRE  PROTECTION. 

CHAPTER  |PAGH 

I.   FIRE  LOSSES 1 

II.   THEORY  AND  PRACTICE  OF  FIRE  PREVENTION 

AND  FIRE  PROTECTION 24 

III.  THEORY  AND  PRACTICE  OF  FIRE  INSURANCE  .       38 

IV.  SLOW-BURNING  OR  MILL  CONSTRUCTION 69 

PART  II.  —  FIRE  TESTS  AND  MATERIALS. 

V.   EXPERIMENTAL  TESTING  STATIONS 113 

VI.   FIRES  IN  FIRE-RESISTING  BUILDINGS  AND  CON- 
FLAGRATIONS       127 

VII.   THE  MATERIALS  OF  FIRE-RESISTING  CONSTRUC- 
TION      207 

VIIL   PERMANENCY  AND  CORROSION 271 

PART  III.  —  FIRE-RESISTING  DESIGN. 

IX.   PLANNING  AND  GENERAL  DESIGN 295 

X.   EFFICIENCY  vs.  FAULTY  CONSTRUCTION 317 

XI.   FIRE-RESISTING  FLOOR   DESIGN,   BEAM-  AND 

GIRDER-PROTECTIONS,  CEILINGS 324 

XII.   COLUMNS  AND  COLUMN  PROTECTIONS 347 

XIII.  FIRE-RESISTING  PARTITIONS 381 

XIV.  FIRE-RESISTING    SHUTTERS,    WINDOWS    AND 

DOORS 418 

XV.   STAIRWAYS  AND  FIRE  ESCAPES 501 

XVI.   ELEVATOR    SHAFTS    AND    ENCLOSURES,    PIPE 

SHAFTS,  CHUTES,  ETC 540 

vii 


yiii  CONTENTS 

PART  IV.  —  FIRE-RESISTING  CONSTRUCTION. 

CHAPTER  PAGE 

XVII.   TERRA-COTTA  FLOORS,    GIRDER-PROTECTIONS, 

ETC 551 

XVIII.   CONCRETE    FLOORS    AND    REINFORCED    CON- 
CRETE    601 

XIX.    COMBINATION    TERRA-COTTA   AND    CONCRETE 

FLOORS 625 

XX.   WALL  CONSTRUCTION 633 

XXI.   ROOFS,  SUSPENDED  CEILINGS,  FURRING 663 

PART  V.  —  SPECIAL  STRUCTURES  AND  FEATURES. 

XXII.   THEATRES 697 

XXIII.  SCHOOLS 740 

XXIV.  RESIDENCES 757 

XXV.   FACTORIES 791 

XXVI.   GARAGES 814 

XXVII.   SAFES,  VAULTS,  METAL  FURNITURE,  ETC 827 

XXVIII.   SPECIAL  HAZARDS 838 

PART  VI.  —  AUXILIARY  EQUIPMENT  AND  SAFEGUARDS. 

XXIX.   AUXILIARY  EQUIPMENT 851 

XXX.   SPRINKLER  SYSTEMS 863 

XXXI.   AUTOMATIC    FIRE    ALARMS,    AND    SPRINKLER 

ALARM  AND  SUPERVISORY  SYSTEMS 908 

XXXII.   SIMPLE  PROTECTIVE  DEVICES.   FIRE  PAILS  AND 

EXTINGUISHERS;  PAINTS  AND  SOLUTIONS.  .  922 

XXXIII.  WATCHMEN,    WATCH-CLOCKS    AND    MANUALS  944 

XXXIV.  STANDPIPES,  HOSE  RACKS  AND  ROOF  NOZZLES  959 
XXXV.   PRIVATE  FIRE   DEPARTMENTS 974 

XXXVI.   INSPECTION  AND  MAINTENANCE  OF  FIRE  PRO- 
TECTIVE DEVICES 986 

XXXVII.   FIRE  DRILLS  . .                                                    .  1000 


I 

I 


PART  I 


FIRE  PREVENTION  AND  FIRE 
PROTECTION 


IX 


FIRE    PREVENTION   AND 
FIRE    PROTECTION 


CHAPTER  I. 
FIRE  LOSSES. 

IN  attempting  any  systematic  study  of  "fire  prevention"  and 
"fire  protection,"  certain" broad  but  indisputable  facts  must  be 
clearly  borne  in  mind  for  a  right  understanding  of  the  tremendous 
importance  of  the  subject  to  this  country  at  the  present  time, 
and  of  the  imperative  need  of  an  entirely  different  national  view 
of  the  fire  problem.  It  will  therefore  be  the  object  of  Part  I  of 
this  volume,  comprising  Chapters  I,  II,  III,  and  IV,  to  show 
conclusively: 

1.  That  the  annual  fire  losses  in  the  United  States  have 
reached  proportions  so  alarming  as  to  make  this  question  one 
of  the  most  vital  problems  before  the  American  people  today. 

2.  That  our  annual  fire  waste  resulting  from  the  burning  of 
buildings  and  contents,   added  to  the  wide-spread  destruction 
of  our  forests  by  fire,  is  undoubtedly  the  greatest  obstacle  to  be 
overcome  by  those  who  believe  in  any  rational  plan  for  the 
conservation  of  our  national  resources. 

3.  That  such  losses  in  buildings  and  contents  can  be  very 
materially  reduced,  as  is  clearly  shown  by  the  experience  of  those 
European  nations  who  have  attacked  the  problem  at  its  proper 
source. 

4.  That  the  people  of  the  United   States  have  heretofore 
relied,  for  immunity  from  the  danger  of  fire  losses,  upon  elaborate 
and  expensive  systems  of  "fire  fighting,"  viz.,  our  very  efficient 
urban  (if  very  deficient  suburban)  fire  departments. 

5.  That  such  city  fire  departments,  while  probably  the  best 
in  the  world  in  both  apparatus  and  personnel,  are  not  preventing 
the  steady  growth  of  our  losses  by  fire. 

1 


FIRE    PREVENTION    AND    FIRE    PROTECTION 


G.  That  insurance  id  not  the  solution  of  the  problem,  but 
that,  on  the  other  hand,  the  very  institution  or  business  of  fire 
insurance  is  threatened  with  extinction  unless  radical  changes 
are  soon  brought  about  in  the  building  of  our  large  cities. 

7.  That  "slow-burning  construction"  or  "mill  construction," 
while  neither  ideal  nor  equal  to  fire-resisting  construction,  is 
admirable  under  limitations  of  cost  and  adaptability,  especially 
if  used  with  auxiliary  equipment;    but  that  the  differences  in 
cost  between  mill  construction  and  thoroughly  fire-resisting  con- 
struction are  fast  disappearing,  and  that  by  the  time  the  latter 
becomes  at  all  universal,  the  former  will  undoubtedly  cost  quite 
as  much  as  more  efficient  methods. 

8.  That  the  only  possible  solution  of  our  national  fire  waste 
resulting  from  the  burning  of  buildings  and  contents  (forest  fires 
being  without  the  scope  of  this  treatise),  lies  in  the  universal 
adoption  of  "fire  prevention"  and  "fire  protection,"  —  as  has 
been  so  successfully  done  in  Europe,  —  embracing  precautionary 
measures  to  prevent  fires,  and  adequate  handling  of  incipient 
fires,  i.e.,  the    confining   and    control  of   fires  independent   of 
departmental  work  so  as  to  reduce  losses  to  a  minimum. 

Annual  Fire  Losses  in  the  United  States.  —  The  following 
table  gives  the  aggregate  property  and  insurance  losses  in  the 
United  States  for  the  years  1875  to  1909  inclusive,  as  compiled 
by  the  National  Board  of  Fire  Underwriters. 


Year 

Aggregate  property  loss 

Aggregate  insurance  loss 

1875 

$78,102,285 

$39,327,400 

1876 

64,630,600 

34,374,500 

1877 

68,265,800 

37,398,900 

1878 

64,315,900 

36,575,900 

1879 

77,703,700 

44,464,700 

1880 

74,643,400 

42,525,000 

1881 

81,280,900 

44,641,900 

1882 

84,505,024 

48,875,131 

1883 

100,149,228 

54,808,664 

1884 

110,008,611 

60,679,818 

1885 

102,818,796 

57,430,709 

1886 

104,924,750 

60,506,564 

1887 

120,283,055. 

69,659,508 

1888 

110,885,665 

63,965,724 

1889 

123,046,833 

73,679,465 

1890 

108,993,792 

65,015,465 

FIRE   LOSSES 


Year 

Aggregate  property  loss 

Aggregate  insurance  loss 

1891 

$143,764,967 

$90,576,918 

1892 

151,516,098 

93,511,936 

1893 

167,544,370 

105,994,577 

1894 

140,006,484 

89,574,699 

1895 

142,110,233 

84,689,030 

1896 

118,737,420 

73,903,800 

1897 

116,354,570 

66,722,145 

1898 

130,593,905 

73,796,080 

1899 

153,597,830 

92,683,715 

1900 

160,929,805 

95,403,650 

1901 

165,817,810 

100,798,645 

1902 

161,078,040 

94,460,525 

1903 

145,302,155 

92,599,881 

1904 

229,198,050 

127,690,424 

1905 

165,221,650 

103,805,402 

1906 

518,611,800 

230,842,759 

1907 

215,084,709 

117,433,427 

1908 

217,885,850 

135,547,162 

1909 

188,705,150 

126,171,492 

Total  

$4,904,619,235 

$2,830,135,615 

The  total  value  of  property  in  the  United  States  which  has 
been  destroyed  by  fire  during  the  thirty-five  years  enumerated 
in  the  above  table,  amounts  to  almost  $5,000,000,000,  and  as 
an  amount  practically  equal  to  the  fire  loss  must  also  be  charged 
to  premiums  paid  and  to  the  maintenance  of  fire  protection,  — 
as  will  be  pointed  out  in  more  detail  in  a  later  paragraph,  —  a 
grand  total  of  $10,000,000,000  results  as  the  fire  tax  on  the 
nation  for  thirty-five  years. 

Increase  in  Losses,  Year  by  Year.  —  The  steady  yearly 
increase  in  our  fire  losses  is  plainly  shown  by  the  above  table. 
Averaging  the  above  losses  by  decades,  it  appears  that,  in  the 
seventies,  the  actual  yearly  loss  was  about  $70,000,000,  in  the 
eighties,  about  $100,000,000,  in  the  nineties,  about  $137,000,000, 
and  from  1900  to  1909  inclusive,  about  $217,000,000.  The 
latter  average  for  the  years  1900  to  1909  was,  of  course,  greatly 
augmented  by  the  stupendous  losses  of  the  year  1906,  including, 
as  they  did,  the  losses  of  the  San  Francisco  conflagration;  but 
conditions  are  so  favorable  for  like  conflagrations  in  many  of 
our  large  cities  that  the  experience  and  losses  of  1906  may  not 


4  FIRE   PREVENTION   AND   FIRE   PROTECTION 

be  considered  altogether  phenomenal,  but  rather  liable  to  dup- 
lication at  any  time. 

What  these  Losses  Mean.  —  As  it  is  difficult,  from  a  bare 
tabulation  of  figures,  adequately  to  realize  what  these  fire  losses 
mean  to  even  as  prosperous  a  nation  as  our  own,  a  few  compari- 
sons will  be  made  with  figures  more  generally  known,  so  as  to 
bring  the  matter  home  in  a  more  forcible  manner. 

The  total  fire  loss  for  the  past  thi^-five  years  has  already 
been  given  as  $4,904,619,235.  The  national  debt  of  the  United 
States,  at  the  highest  point  ever  reached,  on  July  1,  1866, 
amounted  to  $2,733,236,173. 

The  annual  ten-year 'average  fire  loss  up  to  the  end  of  1906 
compares  as  follows  with  the  like  averages  of  the  items  given 
below:* 


Per  cent 

36 

U.  S.  govt.,  total  receipts  

$554,390,238 

37 

Net  earnings,  railways  in  U.  S  

542,274,762 

37 

78 

U.  S.  govt.,  total  ordinary  expenditures.  . 
U.  S.  internal  revenue  receipts 

532,018,116 
253,400,164 

79 

U.  S.  customs  receipts  

252,359,639 

122 

Dividends  paid  by  railways  in  U.  S  

162,124,558 

141 

U.  S.  pensions 

140  861  166 

152 

U.  S.  post-office  receipts 

130,201,926 

156 
157 
165 

Commercial  failures  in  U.  S.,  liabilities.  . 
U.  S.  war-department  expenditures  
Fire  insurance  loss  payments 

126,646,386 
126,465,728 
120  352  198 

180 
242 

(U.  S.  gold  production     )       .   .           , 
1U.  S.  silver  production  }  comlng  value'  •  • 
U.  S.  navy  expenditures  

109,805,439 

81,871,647 

648 

Interest  on  U.  S.  national  debt 

30,568,000 

The  fire  losses  for  the  year  1907  are  thus  summarized  in  Bul- 
letin No.  418  of  the  United  States  Geological  Survey. 

"The  investigation  disclosed  the  fact  that  the  total  cost  of 
fires  in  the  United  States  in  1907  amounted  to  almost  one-half 
the  cost  of  new  buildings  constructed  in  the  country  for  the 
year.  The  total  cost  of  the  fires,  excluding  that  of  forest  fires 
and  marine  losses,  but  including  excess  cost  of  fire  protection 
due  to  bad  construction,  and  excess  premiums  over  insurance 
paid,  amounted  to  over  $456,485,000,  a  tax  on  the  people  exceed- 
ing the  total  value  of  the  gold,  silver,  copper,  and  petroleum 

*  Mr.  Powell  Evans  in  Journal  of  Fire,  June,  1908. 


FIRE    LOSSES  5 

produced  in  the  United  States  in  that  year.  The  cost  of  build- 
ing construction  in  forty-nine  leading  cities  of  the  United  States 
reporting  a  total  population  of  less  than  18,000,000  amounted, 
in  1907,  to  $661,076,286,  and  the  cost  of  building  construction 
for  the  entire  country  in  the  same  year  is  therefore  conserva- 
tively estimated  at  $1,000,000,000.  Thus  it  will  be  seen  that 
nearly  one-half  the  value  of  all  the  new  buildings  constructed 
within  one  year  is  destroyed  by  fire.  .  .  .  This  fire  cost  was 
greater  than  the  value  of  the  real  property  and  improvements 
in  any  one  of  the  following  states :  Maine,  West  Virginia,  North 
Carolina,  North  Dakota,  South  Dakota,  Alabama,  Louisiana, 
Montana." 

Or,  to  look  at  the  matter  in  another  way,  it  has  been  estimated 
that  we  burn  up  during  every  " normal"  week  of  the  year, 
3  theaters,  3  public  halls,  12  churches,  10  schools,  2  hospitals, 
2  asylums,  2  colleges,  6  apartment  houses,  3  department  stores, 
2  jails,  26  hotels,  140  flats  and  stores,  and  1600  homes.  The 
fire  record  for  the  year  1907  shows  that  losses  of  life  or  property 
occurred  in  165,250  buildings,  the  average  damage  to  each  build- 
ing and  its  contents  being  $1667,  about  one-half  of  which  applied 
to  the  buildings  themselves,  and  the  other  half  to  furniture, 
merchandise,  or  other  contents. 

A  most  graphic  mental  picture  of  these  fire  losses  was  given 
by  Mr.  Charles  Whiting  Baker,  editor  of  " Engineering  News," 
in  an  address  before  the  National  Engineering  Societies  on 
"  Conservation  of  Natural  Resources,"  March  24,  1909,  as 
follows: 

"  Suppose  we  try  to  picture  to  ourselves  what  these  many 
millions  of  dollars'  worth  of  valuable  buildings  in  which  fire 
annually  rages  would  look  like.  Suppose  it  were  possible  to 
bring  these  buildings  which  were  visited  by  fire  in  1907  all  to- 
gether and  to  range  them  on  both  sides  of  a  long  city  street. 
Let  us  place  these  buildings  closely  together,  as  they  might  be 
placed  on  an  ordinary  street  in  a  fair-sized  city.  We  will  assume 
that  the  lots  on  which  these  buildings  stand  have  an  average 
frontage  of  65  feet.  .  .  .  This  street,  lined  on  both  sides  with  the 
buildings  visited  by  fire  in  1907,  would  reach  all  the  way  from 
New  York  to  Chicago.  That  is  what  the  annual  fire  loss  of  the 
United  States  represents  —  a  closely  built-up  street,  a  thousand 
miles  long,  with  every  structure  in  it  ravaged  by  the  destructive 
element.  Picture  yourself  driving  along  this  terribly  desolated 


6  FIRE   PREVENTION   AND   FIRE   PROTECTION 

street.  At  every  thousand  feet  you  pass  the  ruins  of  a  build- 
ing from  which  an  injured  person  was  rescued.  Every  three- 
quarters  of  a  mile  there  is  the  blackened  wreck  of  a  house  in 
which  some  one  was  burned  to  death. 

"  Imagine  this  street  before  the  fire  touched  it,  lined  with 
houses,  stores,  factories,  barns,  schools,  churches.  Suppose  the 
fire  starts  at  one  end  of  the  street  on  the  first  day  of  January  and 
is  steadily  driven  forward  by  a  high  wind,  just  as  actually  happens 
in  a  conflagration.  Building  after  building  takes  fire;  and  while 
the  fire  fighters  save  some  in  a  more  or  less  injured  condition, 
the  fire  steadily  eats  its  way  forward  at  the  rate  of  nearly  three 
miles  a  day,  for  a  whole  week,  for  a  whole  month,  for  all  the 
twelve  months  of  the  year.  And  at  the  end  of  1907  did  the  con- 
flagration end?  No;  it  began  on  a  new  street,  a  thousand  miles 
long,  which  was  likewise  destroyed  when  1908  was  ended.  And 
this  same  destruction  is  going  on  today." 

Conflagrations,  or  fires  involving  several  or  many  buildings, 
have  been  common  to  nearly  all  large  cities  in  whatever  country, 
but  no  nation  has  established  such  an  unenviable  record  as  has 
the  United  States. 

From  the  statistics  of  David  D.  Dana,  published  in  Boston 
in  1858,  it  appears  that  "large  or  conflagration  fires"  in  the 
United  States  from  1800  to  1858,  thus  practically  embracing 
the  first  half  of  the  nineteenth  century,  involved  a  loss  of 
$191,000,000.  These  fires  ranged  from  a  few  with  losses  as  low 
as  $20,000,  to  the  fire  in  New  York  City  in  1835  where  the  loss 
was  $17,000,000. 

For  practically  the  latter  half  of  the  same  century,  or,  exactly, 
from  1866  to  1909  inclusive,  the  statistics  published  by  the 
National  Board  of  Fire  Underwriters  show  a  total  loss  from  con- 
flagrations, or  fires  exceeding  a  loss  of  $500,000,  of  $983,234,135. 
This  includes  the  San  Francisco  loss  of  1906.  It  is  worthy  of 
note  that,  while  the  minimum  loss  enumerated  by  the  National 
Board  is  twenty-five  times  greater  than  the  minimum  loss  in- 
cluded by  Dana,  still  the  total  loss  in  the  second  half  of  the 
century  is  over  five  times  that  of  the  first  half.  Also,  the  first 
half  of  the  century  witnessed  26  fires  equalling  or  exceeding 
$1,000,000  loss,  as  compared  with  nearly  150  such  fires  in  the 
second  half. 

A  few  of  the  more  notable  conflagrations  in  the  United  States 
may  be  listed  as  follows: 


FIRE   LOSSES 


1820 

June      10 

Savannah,  Ga.  . 

$3  000  000 

1835 

Dec.     16 

New  York  City  

17,000,000 

1838 

Charleston,  S.  C 

6  000  000 

1839 
1845 
1845 

Sept.     23 
July      19 
April     10 

New  York  City  -  
New  York  City  
Pittsburgh,  Pa.  .  . 

4,000,000 
3,000,000 
1  500  000 

1849 
1850 
1851 

May      18 
July      10 
May       3 

St.  Louis,  Mo  
Philadelphia,  Pa  
San  Francisco,  Cal  

3,000,000 
1,500,000 
3,500  000 

1852 

March 

New  Orleans,  La  

5,000,000 

1866 
1871 

July        4 
Oct.       9 

Portland,  Me     
Chicago,  111.  *.  .  . 

10,000,000 
168  000  000 

1872 

Nov.      9 

Boston,  Mass.*  *  

70,000,000 

1876 

Feb.       8 

New  York  City  

1  750  000 

1879 

Feb.     14 

New  York  City 

1  300  000 

1879 

Feb.     17 

New  York  City  

2  000  000 

1888 

April    30 

New  York  City  

1,140,000 

1889 
1889 

April 
June 

New  York  City  
Seattle,  Wash.  . 

1,900,000 
5  000  000 

1889 
1889 

August 
Nov. 

Spokane,  Wash  
Boston,  Mass  

4,800,000 
3,800,000 

1889 

November 

Lynn,  Mass. 

5  000  000 

1891 
1892 

March  17 
Feb. 

New  York  City  
New  Orleans,  La. 

1,550,000 
1,100,000 

1892 
1892 

April 
Oct. 

New  Orleans,  La  
Milwaukee,  Wis.  . 

1,400,000 
5,000,000 

1893 

Jan. 

Boston,  Mass  

1,030,000 

1893 

March 

Boston,  Mass  

3,000,000 

1896 

Oct. 

Chicago,  111. 

1,150,000 

1897 
1898 

May 
Feb. 

Pittsburgh,  Pa  
Pittsburgh,  Pa. 

2,000,000 
1,400,000 

1898 

Terre  Haute,  Ind  

1,850,000 

1899 

Philadelphia,  Pa.  .  . 

3,000,000 

1900 

July 

Bayonne,  N.  J. 

1,440,000 

1900 
1901 

July 
May 

Hoboken,  N.  J  
Jacksonville,  Fla 

5,500,000 
11,000,000 

1902 
1902 

Feb. 

Feb        8 

Waterbury,  Conn  
Paterson,  N.  J  

1,400,000 
5,800,000 

1903 

Feb      26 

Cincinnati,  Ohio. 

1,500,000 

1904 
1904 

Feb.      7,  8,  9 
Feb 

Baltimore,  Md.f  
Rochester,  N.  Y. 

40,000,000 
3,200,000 

1906 

April     18 

San  Francisco,  Cal.  t  

350,000,000 

1908 

April     12 

Chelsea,  Mass.  §  

12,000,000 

1908 

May       8 

Atlanta  Ga. 

1,250,000 

*  3 1  square  miles  of  buildings  destroyed,  56  insurance  companies  rendered 
insolvent. 

**  65  acres  laid  waste. 

t  Devasted  140  acres  including  1343  buildings. 

t  Earthquake  and  fire  loss,  3000  acres  destroyed,  involving  520  city  blocks. 
25,000  buildings  destroyed,  only  3000  of  which  were  brick  or  stone. 

§  3500  buildings,  covering  275  acres,  destroyed. 

he  comparative  areas  of  the  Chicago,  Baltimore,  and  San 
Francisco  conflagrations  are  illustrated  in  Fig.  1. 

The  causes  or  combinations  of  circumstances  making  such 
conflagrations  possible  are  many.  All  large  cities  contain 
localities  which  are  pregnant  with  conflagration  possibilities, 
principally  due  to  the  rapid,  haphazard  growth  and  construction 


8 


FIRE    PREVENTION    AND    FIRE    PROTECTION 


of  such  cities.  Large  areas  of  wooden  buildings  may  exist,  as 
in  San  Francisco;  or  a  large  store  or  warehouse,  stocked  with 
inflammable  goods,  inadequately  safe-guarded,  as  at  Baltimore, 
may  provide  the  cause.  The  absence  of  fire  walls,  shutters  or 


FIG.  1.  —  Comparative  Areas  of  Chicago,  Baltimore,  and  San  Francisco 
Conflagrations. 

window  protection  may  turn  an  ordinary  fire  into  one  of  great 
magnitude,  while  such  circumstances  as  low-water  pressure, 
delay  in  transmitting  alarm,  bad  judgment  or  disorganization 
of  the  fire  department,  have  all  been  responsible  for  wide-spread 
fires. 


FIRE   LOSSES  9 

The  possible  menace  of  conflagrations  to  the  institution  of 
fire  insurance,  provided  the  future  shows  any  such  ratio  of 
increase  as  has  been  demonstrated  in  the  past,  is  discussed  in 
Chapter  III. 

Cost  of  Fire  Protection  above  Actual  Fire  Loss.  —  In  the 
.  statistics  compiled  by  the  United  States  Geological  Survey  upon 
"The  Fire  Tax  and  Waste  of  Structural  Materials  in  the  United 
States,"*  a  careful  inquiry  was  made  into  the  additional  cost  of 
fire  protection  in  the  year  1907,  over  and  above  the  actual  loss 
by  fire.  The  indirect  losses  of  fire  protection  include  the  in- 
surance loss,  or  the  difference  between  the  total  premiums  paid 
the  insurance  companies  and  the  amounts  paid  to  the  insured; 
the  annual  expense  of  that  proportion  of  all  water  supplies 
necessary  to  furnish  fire  protection  in  excess  of  service  estimated 
as  necessary  for  domestic  consumption;  the  annual  expense  of 
fire  departments,  and  the  annual  expense  of  private  fire  pro- 
tection. 

The  results  of  this  inquiry  are  embodied  in  the  following 
table.* 

These  direct  and  indirect  losses  due  to  fires  and  fire  pro- 
tection should  be  compared  with  the  table  given  in  paragraph 
" Financial  Loss  Involved"  at  the  end  of  this  chapter. 

Per  Capita  Fire  Tax.  —  Bulletin  No.  418  of  the  United 
States  Geological  Survey  also  gives  the  following  statistics  on 
the  per  capita  fire  tax  in  the  United  States  for  the  year  1907. 

2976  cities  and  villages $2. 54 

The  rural  districts $2. 49 

The  per  capita  loss  for  all  cities,  villages,  and  rural  districts 
from  which  returns  were  received,  was  $2.51,  or  a  tax  of  $15.00  a 
year  on  the  head  of  every  family  of  six  persons.  A  comparison 
with  the  existing  per  capita  taxes  in  European  countries  is  given 
in  a  later  paragraph. 

Loss  of  Life  by  Fire.  —  Notable  examples  of  burning  build- 
ings in  which  great  loss  of  life  occurred,  include  the  Hotel  Wind- 
sor in  New  York  City  in  1899;  the  Iroquois  Theater  in  Chicago, 
burned  December  30,  1903,  with  a  loss  of  nearly  600  lives,  mostly 
women  and  children;  the  Boyertown,  Pa.,  opera  house,  burned 
January  13,  1908,  and  costing  almost  200  lives;  the  fire  of 

*  Bulletin  No.  418,  United  States  Geological  Survey. 


10 


FIRE   PREVENTION   AND   FIRE   PROTECTION 


Annual 
loss  and 
expense. 

$215,084,709 
145,604,362 

§       i=       :§ 

$456,486,151 

1     1 

;               :°° 

Investment  in 
construction 
and  equip- 
ment. 

$245,671,676 

...             0      . 

! 

lllll  1 

\l\      §  i 

:  :  :  :  :    § 

...      S: 

Fire  loss: 
TW*I  fir*  i™«  .  $215.084.709 

Fire  Protection:  Insurance: 
Amount  of  fire  premiums  paid  above  amount  of  losses  paid  *  145,604,362 
Cost  of  Water-works,  Chargeable  to  Fire  Service: 
Total  cost  water-works  (construction  and  equipment)  chargeable  to  fire  service  t  245,671,676 
Source  of  water  supply  (construction  and  equipment)  chargeable  to  fire 
«or™™  &fifi.482.220.  .  . 

•     •  •  • 

'      '      '              0      ' 

1 

a 

^£ 
h 

:  :  :       8  : 

:S  :  ;  ;    g5 

•  M    1  ; 

•OO      •      •      •        I>-  GO 

ill  ;ii's   : 
HI  HI  j 

4,603,731.... 
§4,282,54t).... 
40,054,574.... 

natic  sprink- 

0) 

ro 

s 

ya 

3 

J3 

:  :  •    o  •  • 

:  :  :     *  :  : 

...      J3    '•    '. 

Distributing  system  (construction  and  equipment)  chargeable 

•uipp  9  01fi  Q27  tnnsnf  mptal 

i 

cc 

-1 

"1 

p 

s 

Separate  high-pressure  fire  service  
Total  annual  expense  of  water-works,  chargeable  to  fire  servi 
Depreciation  and  taxes,  water-works,  chargeable  to  fire  se 
Interest  charge,  water-  works,  chargeable  to  fire  service.  .  . 
Maintenance,  water-works,  chargeable  to  fire  service  
Fire  Departments: 
Total  cost  of  fire  departments  (construction  and  equipment) 

1.1      •§'•'. 

:  :  :     £  :  I 

:  :  :    $  :\ 

l  H  '£  i  ; 

Depreciation  and  taxes  —  fire  departrru 
Interest  charge  —  fire  departments  — 
Maintenance  —  fire  departments  
Private  Fire  Protection: 
Total  cost,  construction  and  equipment 
lers,  etc.  
Total  annual  private  fire  protection  

FIRE   LOSSES  H 

March  4,  1908,  in  the  schoolhouse  at  Collinwood,  Ohio,  where 
165  pupils  were  burned  or  killed;  and  the  Asch  Building  or 
Triangle  shirt-waist  factory  fire  in  New  York  City,  March  25, 
1911,  in  which  145  lives  were  lost. 

Accurate  statistics  of  deaths  by  fire  are  exceedingly  difficult 
to  obtain,  but  there  is  little  question  that  the  loss  of  life  by  fire 
in  the  United  States  has  grown  rapidly  of  late  years. 

During  the  year  1907,  according  to  information  gathered  by 
the  United  States  Geological  Survey,  fires  caused  the  death  of 
1449  persons  and  the  injury  of  5654.  These  figures  are  incom- 
plete and  perhaps  do  not  represent  more  than  half  the  persons 
who  were  victims  of  fire. 

Many  fire  chiefs  of  large  cities  failed  to  report  any  deaths 
because  such  were  not  properly  included  in  their  annual  reports. 
It  is  safe  to  assume  that  with  the  fire  losses  of  the  United  States 
from  five  to  seven  times  as  great  as  those  in  Europe,  the  number 
of  persons  killed  and  injured  here  is  from  five  to  seven  times 
greater  than  in  Europe.  The  cause  of  this  again,  in  many  in- 
stances, is  faulty  construction  of  buildings,  and  inappreciation  on 
the  part  of  cities  of  the  responsibility  to  safeguard  the  lives  of 
their  citizens,  or  ignorance  of  what  is  demanded  to  protect  against 
fire. 

A  somewhat  recent  report  by  United  States  Consul  Joseph  I. 
Brittain,  stationed  at  Prague,  Bohemia,  states  that  "there  has 
not  been  a  life  lost  in  consequence  of  a  fire  during  the  past  fifteen 
years  in  that  city  of  over  500,000  population,  and  the  loss  of 
property  from  fires  during  the  past  three  years  has  been  less  than 
120,300  annually." 

Comparative  Losses  in  United  States  and  Europe.  —  If 
>ur  enormous  fire  losses  were  absolutely  unavoidable,  specula- 
tion as  to  the  improvement  of  conditions  would  be  idle.  But 
;hat  such  property  losses  are  preventable  is  irrefutably  shown 
)y  comparing  statistics  of  fire  losses  in  the  United  States  and  in 
Europe. 

First,  a  comparison  may  be  made  between  the  conservation 
•xhibited  by  European  countries  and  the  reckless  waste  per- 
aitted  in  the  United  States.  From  special  reports  of  United 
States  Consuls  in  Europe,  it  has  been  shown  by  the  committee 
n  statistics  of  the  National  Board  of  Fire  Underwriters  that  the 
verage  per  capita  loss  in  six  European  countries  for  a  period 
f  five  years  was  $0.33,  distributed  as  follows: 


12 


FIRE    PEEVENTION   AND    FIRE   PROTECTION 


Country. 

Years. 

Fire  loss, 
annual  average. 

Population  1901. 

Loss 
per 
capita. 

Austria/ 

1898-1902 

$  7,601,389 

26,150,597 

$0.29 

Denmark               .    . 

1901 

660,924 

2,588,919 

.26 

France        

1900-1904 

11,699,275 

38,595,500 

.30 

Germany  

1902 

27,655,600 

56,367,178 

.49 

Italy 

1901-1904 

4,112,725 

32,449,754 

.12 

Switzerland     

1901-1903 

999,364 

3,325,023 

.30 

Official  fire  losses  in  the  states  of  Maine,  Massachusetts,  New 
Hampshire,  and  Ohio  for  a  period  of  five  years  were  as  follows: 


State. 

Five  years. 

Fire  loss 
average. 

Population. 

Loss 
per 
capita. 

Maine 

1901-05 

$2,240,158 

$    694,647 

$3.22 

Massachusetts  

1901-05 

6,285,891 

2,844,068 

2.21 

New  Hampshire.  .  .  . 
Ohio  

1901-05 
1901-05 

1,174,061 
7,502,561 

411,588 
4,157,545 

2.85 
1.80 

giving  an  average  per  capita  loss  of  $2.12. 

The  total  per  capita  fire  loss  in  the  United  States  for  the  five 
years  ending  with  1907  was  $3.02,  or  nearly  ten  times  as  much 
as  the  European  average  quoted  above. 

Or,  again,  comparing  cities  with  cities,  the  result  in  thirty 
foreign  cities  gave  an  average  per  capita  loss  of  $0.61  as  com- 
pared with  $3.10  in  the  five  years'  average  of  252  cities  in  the 
United  States.  The  following  table,  compiled  from  statistics 
gathered  by  the  United  States  Geological  Survey  and  Bureau 
of  Manufactures,*  gives  a  comparison  of  fire  losses  in  America 
and  European  cities  of  approximately  the  same  population. 

Had  the  United  States  a  per  capita  loss  of  $0.33  as  given  above 
for  European  countries,  instead  of  an  actual  per  capita  loss  of 
$2.51  for  the  year  1907  (based  on  a  population  of  85,532,761), 
then  the  total  fire  loss  in  the  United  States  in  that  year  would 

*  Bulletin  No.  418  of  the  United  States  Geological  Survey.  "The  Fire  Tax 
and  Waste  of  Structural  Materials  in  the  United  States,"  by  Herbert  M.  Wilson 
and  John  J.  Cochrane. 


FIRE    LOSSES 


13 


European  losses  for  1904. 


City. 

Population. 

Fire  loss. 

Per 

capita. 

Paris,  France 

2  714  068 

$1  266  282 

$0  47 

Frankfort,  Germany  

324  500 

99  492 

0  31 

St.  Petersburg,  Russia  
Birmingham,  England  
Sheffield,  England  

1,500,000 
550,000 
426,686 

2,128,541 
226,506 
75  989 

1.42 
0.41 
0  18 

Toulon,  France 

101  602 

55  391 

0  55 

Bremen,  Germany  

203,847 

78  372 

0  38 

Molenbeek,  Belgium 

63  678 

106  150 

1  67 

Laeken,  Belgium   . 

31,121 

22  349 

0  72 

Etterbeek,  Belgium  

23,992 

19,504 

0  80 

United  States  losses  for  1907. 


Chicago,  Illinois  

2,049,185 

3,937,105 

1  43 

Cincinnati,  Ohio 

345  230 

1  971  217 

5  70 

Philadelphia,  Pennsylvania.  . 
Baltimore,  Maryland  

1,441,737 
553,669 

2,093,522 
916,603 

1  45 
1.66 

Cleveland,  Ohio. 

460,000 

515  194 

1  12 

Atlanta,  Georgia  
St.  Paul,  Minnesota  

104,984 
204,000 

225,237 
522,447 

2.15 
2.56 

Evansville,  Indiana  

63,957 

196,702 

3.08 

Oshkosh,  Wisconsin  

31,033 

80,500 

2.59 

Easton,  Pennsylvania    .  . 

25,238 

32,073 

1.27 

have  amounted  to  only  $28,623,290,  or  a  saving,  in  fire  waste 
alone,  of  $186,461,419. 

In  the  year  1907  there  were  but  thirty-five  fires  in  Great 
Britain  that  averaged  over  $50,000  loss,  and  not  one  that  ex- 
ceeded $400,000.  In  January,  1908,  fire  destroyed  $24,000,000 
worth  of  property  in  the  United  States. 

The  following  table*  gives  the  population,  number  of  fires, 
and  fire  losses  for  nine  Italian  cities  for  the  five-year  period 
ending  December  31,  1909.  The  per  capita  losses  should  be 
compared  with  those  shown  by  American  cities  in  the  previous 
table. 

*  1910  Proceedings  of  National  Board  of  Fire  Underwriters. 


14 


FIRE   PREVENTION   AND    FIRE    PROTECTION 


38 

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(In  1907) 

(In  1906) 

Milan  

574,600 

949 

$694,407 

$700 

$300 

$1981 

1.65 

$1.20 

(In  1905) 

(In  1907) 

Turin  .... 

366,846 

267 

49,624 

186 

$58 

$532 

.72 

0.13 

(In  1905) 

(In  1909) 

Florence  

223,200 

189 

38,100 

201 

$102 

$298 

.84 

0.17 

(In  1906) 

(In  1905) 

Venice 

174,324 

152 

62,981 

414 

$227 

$508 

.87 

0.36 

(In  1905) 

(In  1907) 

Padova.  .  .  . 

81,545 

97 

5,200 

50 

$26 

$86 

1.16 

0.06 

(In  1909) 

(In  1907) 

Brescia  

74,386 

117 

57,016 

487 

$89 

$1660 

1.58 

0.76 

(In  1908) 

(In  1907) 

Ravenna.  .  . 

66,740 

9 

1,179 

131 

$33 

$207 

.13 

0.02 

(In  1908) 

(In  1909) 

Savona 

47,100 

50 

11,456 

228 

$123 

$342 

1.06 

0.24 

*  Parma..  .  . 

50,090 

140 

17,048 

122 

2.08 

0.34 

*  For  year  of  1909;   no  previous  records. 

Frequency  of  Fires  in  United  States  and  Europe  Com- 
pared. —  In  such  large  cities  in  the  United  States  as  New  York, 
Boston,  Philadelphia,  etc.,  the  annual  number  of  fires  has  been 
steadily  increasing  year  by  year,  but  in  far  greater  proportion 
than  the  growth  of  population,  as  has  been  shown  in  a  previous 
paragraph.  The  frequency  of  fires  has  also  increased  of  late 
years  in  such  foreign  cities  as  London,  Berlin,  and  Paris,  probably 
due  to  the  increasing  complexities  of  modern  living;  but  whereas 
the  total  American  fire  losses  have  increased  out  of  all  propor- 
tion to  city  growth  or  expansion,  fire  losses  in  Continental  cities 
have  not  materially  increased.  Thus  the  average  fire  loss  in 
Boston  is  now  about  $2,000,000,  while  in  an  average  European 
city  of  equal  population  the  fire  loss  will  seldom  be  found  to 
range  over  $150,000,  and  this  in  spite  of  the  usually  marked 
superiority  of  our  fire-fighting  facilities. 

The  committee  on  statistics  of  the  National  Board  of  Fire 
Underwriters  found  that  the  number  of  fires  per  1000  of  popula- 
tion averaged  4.05  in  cities  of  the  United  States,  compared  with 
0.86  for  similar  cities  in  Europe. 

Extent  of  Fires  in  United  States  and  Europe  Com- 
pared. —  In  the  investigations  carried  out  by  the  Technologic 


FIRE   LOSSES  15 

Branch  of  the  United  States  Geological  Survey,  it  was  found 
that  a  prominent  cause  of  the  tremendous  fire  waste  in  the  United 
States  was  due  to  fires  extending  beyond  the  limits  of  the  build- 
ings in  which  they  started.  "Exact  figures  as  to  the  losses  due 
to  exposure  were  not  obtainable,  but  the  most  conservative 
estimate  indicates  that  at  least  27  per  cent,  of  the  losses  resulted 
from  fires  extending  beyond  the  building  of  origin."  * 

On  the  other  hand,  by  referring  to  the  Special  Consular  Re- 
ports made  in  1892  to  the  State  Department  of  the  United 
States,  giving  fire  and  building  regulations  in  foreign  countries, 
it  will  be  found  that  in  such  cities  as  Havre,  Rouen,  Milan,  Rome, 
Brussels,  Antwerp,  and  Leeds,  Sheffield,  and  Bristol  in  England, 
every  fire  in  the  year  1890  was  confined  to  the  building  in  which 
it  originated;  while  in  Dresden,  Florence,  Vienna,  and  other 
cities,  every  fire  was  confined  to  the  floor  on  which  it  originated. 

In  London,  in  1889,  of  a  total  of  2892  fires,  all  but  six  were 
confined  to  the  building  in  which  they  originated.  The  report 
states  that  "Legislation  as  far  back  as  1666  has  encouraged  or 
enforced  the  use  of  brick  or  stone  in  repair  and  emplacement, 
with  the  result  that  few,  if  any,  timber  structures  now  survive." 

In  Hamburg,  out  of  a  total  of  682  fires  in  1890,  659  were  con- 
fined to  the  floor  where  they  started,  669  to  the  building,  while 
only  10  fires  extended  to  adjoining  property.  A  conflagration, 
or  the  extension  of  fire  beyond  the  immediately  adjoining  prop- 
erty, had  not  been  known  since  1842.  In  Glasgow  all  but 
14  fires  in  a  tot  ad  of  504  were  confined  to  the  floor  where  they 
started. 

It  must  also  be  borne  in  mind  that  many  of  these  results  are 
obtained  in  spite  of  what  Americans  would  consider  the  most 
inadequate  fire-fighting  facilities.  Thus  in  Rome,  where,  in 
1890,  328  fires  were  practically  all  confined  to  the  room  of  origin, 
the  extinguishment  of  fires  was  thus  described  by  Consul- 
General  Bourn: 

Buckets  and  fire  extinguishers  are  chiefly  used  for  extin- 
guishing fires.  If  these  are  not  sufficient,  small  hose,  perhaps 
If  inches  in  diameter,  are  brought  into  service.  But  the  force 
of  water  in  many  parts  of  the  city  is  not  great,  although  the 
supply  is  very  abundant.  If  the  hydrant  pressure  is  not  suffi- 
cient, small,  portable  fire  engines  are  used,  and  in  cases  of  great 
emergency  there  is  one  steamer,  but,  as  it  is  so  seldom  required, 

*  Herbert  M.  Wilson  in  Transactions  Am.  Soc.  C.  E.,  Vol.  LXV,  page  277. 


16  FIRE   PREVENTION   AND   FIRE   PROTECTION 

no  proper  arrangements  exist  for  bringing  it  into  service.  The 
last  time  the  steamer  was  called  out  it  was  over  two  hours  before 
it  was  ready  to  throw  water  on  the  fire. 

In  Vienna  it  was  reported:  " There  is  no  case  known  in  this 
city  where  a  fire  has  extended  beyond  the  building  in  which  it 
originated,  and  even  hardly  any  cases  are  known  where  a  fire 
extended  beyond  the  floor  on  which  it  originated.  This  is  pre- 
vented by  the  solidity  of  the  buildings,  by  strict  fire  regulations, 
and  by  a  pretty  well-trained  fire  department,"  the  latter  con- 
sisting of  "five  steam  engines,  but  very  seldom  called  into  action, 
and  a  large  and  sufficient  number  of  hand  engines." 

Causes  of  Foregoing  Differences.  —  The  striking  contrasts 
between  the  losses,  frequency,  and  extent  of  fires  in  the  United 
States  as  compared  with  European  countries  as  given  above,  are 
due  to  four  principal  causes. 

First:  Differences  in  the  view-point  and  in  the  civic  respon- 
sibility of  the  individual  in  the  United  States  and  in  Europe,  and 
the  consequent  laws  or  regulations  which  govern  the  individual. 

Second:  Differences  in  general  character  of  buildings  outside 
of  congested  areas. 

Third:  Differences  in  thoroughness  of  construction  and  main- 
tenance. 

Fourth:  Differences  in  regulations  and  their  enforcement  re- 
garding especially  hazardous  materials  and  conditions. 

A  candid  inquiry  into  the  first-mentioned  differences,  viz.,  the 
individual  view-point  and  responsibility,  will  disclose  the  fact 
that  our  national  fire  losses  are  principally  caused  by  the  moral 
attitude  of  the  individual  toward  the  phenomenon  of  fire  waste. 

European  cities  long  ago  learned  the  lesson  that  safety  to  the 
individual  means  safety  to  the  whole  community,  and  vice  versa. 

They  have  learned  that  fire  waste  emanates  in  larger  part 
from  either  criminal  indifference  or  criminal  intent,  and  that  to 
this  extent  it  is  preventable  through  laws  which  go  directly  to 
the  root  of  the  evil  by  holding  the  individual  citizen  to  a  rigid 
accountability  for  every  act  of  omission  or  commission  which 
tends  to  increase  the  danger.  In  all  parts  of  Europe  where  the 
Code  Napoleon  prevails,  the  law  of  Voisinage  holds  the  landlord 
responsible  for  his  negligence  to  all  concerned,  tenants  or  neigh- 
bors, and  if  fire  originates  from  carelessness  of  tenant,  he  is  held 
responsible  to  all  concerned,  landlord  or  neighbors.  This  law 
places  the  responsibility  where  it  belongs  and  works  automatically 
in  making  everyone  interested  in  having  his  premises  as  safe  as 


FIRE    LOSSES  17 

they  can  be  made  by  human  foresight.  This  is  not  only  strictly 
logical,  but  in  harmony  with  the  attitude  of  every  civilized  gov- 
ernment in  dealing  with  the  spread  of  contagion.* 

It  is  just  some  such  civic  responsibility  which  is  needed,  and 
needed  very  soon,  in  all  American  cities  and  towns.  Respon- 
sibility of  the  individual  to  the  community,  which  will  cause 
the  individual  to  contribute  to  the  public  safety  in  matters  of 
building  construction  by  erecting  structures  which  will  not  prove 
a  menace  to  his  neighbors;  and  responsibility  of  the  community 
to  the  individual,  in  that  those  investors  who  improve  their  land 
by  the  erection  of  more  costly  and  permanent  structures  shall 
not  be  allowed  to  suffer  constant  hazard  through  irresponsible 
neighbors  who  have  no  thought  or  care  of  their  civic  duties. 

It  is  now  a  trite  saying  that  "  fireproof  buildings  must  stand 
in  fireproof  cities,"  but  this  statement  contains  the  whole  truth 
of  the  matter  of  fire  protection.  If  American  cities  are  not  to 
suffer  such  conflagrations  as  have  occurred  at  Chicago,  Boston, 
Paterson,  Baltimore,  and  San  Francisco,  besides  many  other 
lesser  ones;  if  the  realization  of  this  tremendous  financial  drain 
is  once  grasped  in  an  effort  to  lessen  it;  if  it  be  admitted  that 
isolated  buildings  surrounded  by  severe  risks  cannot  withstand 
conflagration  conditions,  then  the  achievement  of  fire-resisting 
cities  (or  at  least  the  congested  areas  therein)  must  be  made 
possible  by  uniform  fire-resisting  construction  throughout. 

In  the  United  States  we  are  so  prone  to  consider  the  rights  of 
the  individual  that  we  are  apt  to  overlook  the  rights  of  the  aggre- 
gation of  individuals.  It  is  not  denied  that  municipal  building 
regulations  adopted  by  any  American  city,  requiring  uniform 
fire-resistive  building  construction  after  any  fixed  date,  would 
give  rise  to  seeming  injustices  and  hardships;  but  if  laws  requir- 
ing the  remodeling  of  present  risks  were  also  rigidly  enforced, 
in  addition  to  laws  covering  the  erection  of  new  buildings,  the 
hardships  would  soon  be  equalized,  and  benefit  accrue  to  the  com- 
munity in  the  way  of  reduced  fire  losses,  reduced  insurance 
premiums,  reduced  expenses  for  maintaining  fire-fighting  equip- 
ments, and  added  security  to  life  and  property  interests. 

The  second  great  cause  of  our  excessive  fire  loss  is  to  be  found 
in  the  materials  of  construction  employed  in  localities  outside 
of  the  congested  areas  of  large  cities.  Nearly  all  of  our  large 
American  cities  now  have  fire  limits  defining  the  congested 

*  Mr.  A.  F.  Dean  in  National  Fire  Protection  Association  "  Quarterly." 


18 


FIRE   PREVENTION   AND   FIRE   PROTECTION 


areas  within  which  frame  buildings  may  not  be  erected,  but, 
save  in  years  when  conflagration  sweeps  over  some  city,  it  is 
found  that  such  congested  areas  do  not  contribute  the  greater 
proportion  of  the  fire  loss.  Thus  in  the  year  1907,  when  the 
actual  fire  losses  to  buildings  and  their  contents  in  the  United 
States  amounted  to  about  $215,084,709,  the  loss  in  brick, 
concrete,  or  other  slow-burning  construction  totaled  only 
$68,425,267,  while  double  that  amount,  or  $146,695,442  was 
on  losses  in  frame  buildings.*  In  that  year  the  total  urban 
and  rural  losses  were  practically  the  same,  but  while  the  loss 
on  contents  was  naturally  greater  in  the  urban  property,  still  the 
loss  on  buildings  was  greater  in  the  rural  districts. 

Taking  the  losses  geographically,  the  following  table  and 
comment  on  same  are  quoted  from  the  paper  by  Mr.  Wilson 
previously  referred  to  as  giving  statistics  gathered  by  the  United 
States  Geological  Survey. 


Geographical  divisions  of  states. 

Total  popu- 
lation. 

Total  fire 
loss. 

Fire 
loss  per 
capita. 

North  Atlantic 

(  Me.,  N.  HM  Vt.,  Mass.,  R.  I., 
1      Conn.,  N.  Y.,  N.  J.,  and  Pa. 

23,779,013 

$59,447,532 

$2.50 

South  Atlantic 

{      N.'  C.  ,  S.  C.  ,  Ga.  ,  and  Fla.  ' 

11,574,988 

25,349,223 

2.19 

North  Central 

(  Ohio,  Ind.,  111.,  Mich.,  Wis., 
I     Minn.,  Iowa,  Mo.,  N.  Dak., 

29,026,645 

68,793,148 

2.37 

(      S.  Dak.,  Neb.,  and  Kans. 

South  Central 

(  Ky.,  Tenn.,  Ala.,  Miss.,  La., 
\     Tex.,  Okla.,  and  Ark  

16,368,558 

59,908,922 

3.66 

(Mont.,  Wyo.,  Col.,  N.  Mex., 

Western 

Ariz.,  Utah,  Nev.,  Wash., 

4,783,557 

12,676,426 

2.65 

(     Ore.,  and  Cal. 

Studying  these  fire  losses  by  geographical  divisions  of  states, 
—  a  division .  generally  used  by  the  Census  Bureau  —  as  set 
forth  in  the  above  table,  a  remarkable  feature  is  the  large  per 
capita  loss  in  the  southern  states,  namely,  $3.66,  or  more  than 
$1.00  in  excess  of  the  per  capita  loss  in  any  other  division.  The 
cause  lies  in  the  fact  that  the  southern  states  are  well-timbered, 
and,  in  addition,  suffer  from  the  handicap  of  inefficient  fire  pro- 
tection in  the  cities  and  villages. 

Throughout  nearly  all  European  countries,  save  in  Norway 
and  Sweden  where  wooden  construction  is  prevalent,  the  erec- 
tion of  frame  buildings  is  prohibited  in  all  municipalities,  and 

*  The  number  of  fires  in  brick,  iron,  and  stone  buildings  was  36,140,  while 
the  number  of  fires  in  frame  buildings  was  129,117. 


FIRE    LOSSES 


19 


ew  are  erected  in  rural  districts.  It  is  seldom  that  any  con- 
siderable number  of  frame  buildings  are  to  be  found,  while  a 
whole  community  of  inflammable  structures  (as  is  common 
enough  with  us)  is  almost  unknown. 

Compare,  for  instance,  the  following  table*  showing  the  total 
number  of  brick,  stone,  or  wooden  buildings  standing  in  1905  in 
Massachusetts,  with  the  similar  table  giving  the  same  data  for 
France. 


Place. 

Area, 
square 
miles. 

Popu- 
lation. 

Number  of  buildings. 

Brick 
or 
stone. 

Frame. 

Total. 

Massachusetts: 
Boston 

37.04 
23 
6.74 

? 

41 
36 
32 
16.35 
12.4 
ill 
8.8 
8.62 
20 
6 

17i 
13?66 

593,598 
47,782 
97,426 
37,277 
29,108 
105,697 
26,006 
37,818 
49,124 
94,845 
77,025 
37,990 
19,638 
36,694 
25,000 
28,067 
69,188 
26,239 

27,000 
138 
654 
1,030 
41 
563 
87 
324 
1,789 
1,058 
420 
127 
104 

'"425 

47 
417 
90 

59,000 
9,436 
13,436 
5,736 
5,478 
12,438 
5,456 
6,908 
3,336 
16,246 
14,962 
6,750 
5,220 

'  3,900 
5,775 
12,229 
3,500 

86,000 
9,564 
14,090 
6,766 
5,519 
13,001 
5,543 
7,232 
5,125 
17,304 
15,382 
6,877 
5,324 
8,972 
4,325 
5,822 
12,646 
3,590 

Brockton  
Cambridge 

Chelsea  
Everett 

Fall  River  

Gloucester  
Haverhill  

Holyoke  
Lowell 

Lynn  
Maiden                                    .    . 

Medford  

Newton       

Pittsfield 

Quincy  
Somerville 

Walthan 

Year. 

Area, 
square 
miles. 

Popula- 
tion. 

Number  of  buildings. 

Brick 
or 
stone. 

Frame. 

Total. 

France 

1904 
1904 
1904 
1904 
1901 
1904 
1904 
1904 

4 

9 
27* 
30 

Y 
15* 
18 

130,196 
491,161 
127,027 
2,714,068 
459,099 
132,990 
110,000 
101,602 

41,972 
9,421 

'  9,666 
11,232 
7,873 

'  5,4i5 

"  157 

12,500 
47,387 
9,421 

433 
9,000 
11,232 
8,030 

1  Havre 

2  Marseilles 

3  Nice 

4  Paris  

5  Lyons     .           

6  Nantes 

7  Rheims  

8  Toulon     

*  From  "  Proceedings  of  the  National  Board  of  Fire  Underwriters." 


20  FIRE    PREVENTION    AND    FIRE    PROTECTION 

Of  course  the  conditions  noted  above  are  primarily  due  to  the 
relatively  high  cost  of  lumber  in  European  countries;  while  in 
the  United  States  lumber  has  been  available,  cheap,  and  most 
readily  adaptable  to  building  uses. 

Regarding  the  third  cause  of  our  fire  waste,  viz.,  lack  of 
thoroughness  of  construction  and  maintenance  of  fire  protection 
appliances,  it  cannot  be  denied  that,  while  our  buildings  are 
generally  higher  and  larger  than  in  European  countries,  yet  they 
are  more  carelessly  constructed  and  less  efficiently  inspected  by 
proper  authorities,  as  is  pointed  out  in  more  detail  in  Chapter  X, 
—  while  the  maintenance  and  inspection  of  our  fire  protection 
auxiliary  appliances  is  generally  very  perfunctory. 

The  fourth  cause  under  discussion,  namely  the  differences  in 
regulations  and  their  rigid  enforcement  regarding  special  hazards, 
may  be  admirably  illustrated  by  comparing  our  recklessness  and 
carelessness  regarding  such  matters  as  lighting,  heating,  the  care 
and  storage  of  paints,  highly  inflammable  liquids,  and  explosives, 
with  the  conditions  obtaining,  for  instance,  in  Berlin,  Germany, 
as  given  by  the  Consul-General  to  that  city: 

Another  important  factor  in  the  case  is  the  strict  and  care- 
fully enforced  regulations  concerning  the  storage,  handling,  and 
transportation  of  highly  inflammable  substances  and  explosives. 
The  scrutiny  of  the  building  police  extends  to  every  detail  of 
apparatus  for  heating  and  illumination.  The  wires  of  electric 
lighting  plants  must  be  inclosed,  wherever  they  may  be  located 
inside  a  building,  in  non-combustible  sheaths  or  tubing,  with 
every  practicable  provision  against  breakage  or  short  circuits. 
The  construction  and  setting  of  stoves,  the  thickness  of  walls  and 
floor  foundations  in  proximity  to  stoves,  furnaces,  and  fireplaces 
of  all  kinds,  the  construction  of  flues,  ash  bins,  and  chimneys, 
are  all  carefully  regulated  and  subject  to  periodical  inspection 
by  the  police.  Gas  stoves  must  be  supplied  with  gas  through 
fixed  iron  pipes;  rubber  tubing  may  not  be  used  for  that  purpose. 
If  any  flexible  tube  is  used  it  must  be  sheathed  with  asbestos. 
Finally,  every  chimney,  whether  in  use  or  not,  provided  it  is 
connected  with  an  inhabitated  building,  must  be  periodically 
cleaned  by  a  member  of  the  authorized  force  of  chimney  sweeps. 
The  net  result  of  the  whole  enforced  system  of  construction, 
maintenance,  and  constant  inspection  is  the  practical  immunity 
of  Berlin  from  serious  conflagrations  and  the  important  economies 
thereby  secured  in  losses  by  fire  and  expenses  of  insurance. 

'Financial  Loss  Involved.  —  While  fire  losses  cannot  be 
obliterated  by  any  means,  still,  if  the  people  of  the  United  States 
would,  through  adequate  laws,  regulations,  and  an  awakening 


FIRE    LOSSES 


21 


of  a  proper  civic  responsibility,  approach  or  equal  the  conditions 
obtaining  in  Europe  today,  then  would  our  "  conflagration " 
losses  become  practically  nil,  using  the  word  " conflagration" 
in  the  European  acceptation,  viz.,  the  spread  of  fire  beyond  the 
single  building  of  origin.  Fires  in  individual  buildings  would 
still  continue,  and  substantial  losses  would  still  remain,  but  the 
increased  protection  afforded  by  uniform  fire-resisting  construc- 
tion would  so  reduce  the  expenses  incidental  to  fire  protection 
that  the  saving  would  be  stupendous. 

The  following  table,  from  Mr.  Wilson's  paper  before  referred 
to,  gives  the  1907  fire  loss  and  outlay  in  the  United  States,  with 
a  comparison  showing  the  probable  annual  loss  if  the  buildings 
were  as  nearly  fire-resisting  as  in  Europe. 


United  States, 
1907. 

Per 
capita. 

United  States, 
if  buildings 
were  as  nearly 
fire-resisting 
as  in  Europe. 

Per 
capita. 

Total  loss  by  fire  

$215,084,709 
145,604,362 

28,856,235 
48,940,845 
18,000,000 

$41,000,000 
28,000,000 

6,000,000 
10,000,000 
5,000,000 

Excess  of  premiums  over 
insurance  paid  

Annual  expense  of  water- 
works,  chargeable  to 
fire  service 

Annual   expense   of   fire 
departments. 

Annual   expense   of   pri- 
vate fire  protection.  .  . 

Total  fire  waste  

$456,486,151 

$5.34 

$90,000,000 

$1.05 

Total  loss  by  fire  .  . 
Annual   expense   of   fire 
protection   .           .... 

$215,084,709 
241,401,442 

$2.54 
2.82 

$41,000,000 
49,000,000 

$0.48 
0.57 

Thus  our  preventable  fire  waste,  according  to  European  ex- 
perience, amounts  to  more  than  $366,000,000  annually,  or  nearly 
enough  to  build  a  Panama  Canal  each  year. 

Waste  of  Structural  Materials.  —  "It  is  evident  that  some- 
thing must  be  done  to  stop  the  unnecessary  waste  of  structural 
materials.  Certain  of  these  materials,  such  as  wood  and  iron, 
are  not  inexhaustible  by  any  means,  but  are  even  approaching 


22  FIRE   PREVENTION   AND   FIRE    PROTECTION 

exhaustion.  In  order  to  obtain  the  best  use  from  these  materials 
in  the  future,  they  must  be  used  with  a  less  lavish  hand.  Waste 
means  increased  cost  in  the  very  near  future. 

"  The  known  supplies  of  high-grade  iron  ores  in  the  United 
States  are  estimated  at  3,840,000,000  tons,  and  unless  the  present 
increasing  rate  of  consumption  is  curtailed,  they  cannot  last  be- 
yond the  middle  of  the  present  century.  There  are,  in  addition, 
59,000,000,000  tons,  or  nearly  twenty  times  the  amount  of  low- 
grade  iron  ore,  which  undoubtedly  will  be  used  when  the  con- 
ditions of  the  market  warrant  it.  To  increase  the  life  of  these 
iron-ore  supplies,  it  is  evident  that  the  people  of  the  United 
States  must  soon  turn  to  concrete-making  materials,  brick,  tile, 
and  other  clay  products,  and  building  stones,  as  substitutes  for 
the  more  perishable  timber  and  the  more  limited  metal  supplies. 
From  the  above,  a  study  of  the  causes  of  waste  of  structural 
materials  is  evidently  of  prime  necessity.  The  first  source  of 
such  waste  has  been  shown  to  be  fires.  A  second  source,  and 
one  closely  related  to  fire  losses,  is  that  due  to  waste  of  iron  and 
steel  placed  underground  in  city  water  mains  or  in  pumping 
plants,  on  account  of  fire  and  conflagration  protection.  .  .  . 

"  In  order  that  this  waste  may  be  brought  to  the  attention  of 
the  public  and  the  law  makers,  and  in  order  that  the  discrepancy 
in  cost  between  wood  and  less  inflammable  materials  of  con- 
struction may  be  reduced,  thus  encouraging  the  use  of  non- 
inflammable  materials,  the  investigations  on  which  the  above 
data  are  based  were  undertaken.  It  is  believed  that  through 
dissemination  of  information  as  to  the  local  availability  of  cement- 
making  materials,  of  gravel  and  sand  suitable  for  concrete  con- 
struction, of  clay  suitable  for  brick-  and  tile-making,  and  through 
tests  and  investigations  which  will  show  the  most  appropriate 
method  of  mixing  and  proportioning  these  materials,  and  of 
designing  them  with  the  minimum  amount  of  each  material 
which  may  suffice  its  purpose,  the  cost  of  constructions  will  be 
reduced  and  the  use  of  such  materials  be  encouraged. 

"  Within  the  past  few  years  marvelous  strides  have  been  made 
in  the  substitution  of  iron  and  steel  for  wood,  due  to  the  inves- 
tigations of  engineers,  physicists,  and  chemists  into  the  prop- 
erties of  these  materials  and  the  great  amount  of  attention 
given  to  their  fabrication  by  manufacturers  and  architects. 
More  recently  the  engineering  and  technical  professions  have 
advanced  to  a  great  extent  the  uses  of  cement  in  concrete  manu- 


FIRE    LOSSES  23 

factures,  but  in  a  vastly  greater  period  practically  nothing  has 
been  done  toward  ascertaining  the  physical  and  chemical  prop- 
erties and  the  better  modes  of  manufacture  and  use  of  the 
products  of  clay  and  stone.  With  these  objects  in  view,  the 
Government,  as  the  largest  consumer  of  such  materials,  is  under- 
taking such  tests  and  investigations  as  may  develop  the  most 
suitable  of  these  less  perishable  building  materials  for  each  par- 
ticular use  and  locality.  These  tests  have  in  view  the  establish- 
ing of  the  physical  properties  of  these  materials,  the  suggestion 
of  improved  methods  of  manufacture  with  a  view  to  economy, 
improved  methods  of  mining  and  marketing  in  order  to  im- 
prove the  quality,  reducing  the  quantity  and  cost,  and  extend- 
ing the  life  of  such  materials.  The  investigations  include  the 
assembling  of  information  relative  to  the  most  fire-resisting  and 
fireproof  forms  of  construction,  the  former  for  the  prevention 
of  conflagrations  due  to  secondary  or  exposure  fires  and  the 
latter  for  the  prevention  of  the  destruction  of  the  buildings  in 
which  the  fires  originate."* 

*  Herbert  M.  Wilson  in  Trans.  Am.  Soc.  C.  E.,  Vol.  LXV,  page  287. 


CHAPTER  II. 

THEORY  AND  PRACTICE  OF  FIRE  PREVENTION  AND 
FIRE  PROTECTION.* 

Fire  Prevention  Defined.  —  Fire  prevention,  or  preventive 
measures  against  fire,  has  to  do  with  the  causes  of  fire,  such 
as  common  hazards,  special  hazards,  carelessness,  and  incen- 
diarism; also  with  educational  measures,  and  building  laws,  or 
other  regulations  which  deal  with  preventive  safeguards. 

Yearly  Increase  in  Number  of  Fires.  —  A  constant  increase 
in  the  causes  of  fire,  and  hence  in  the  number  of  fires,  seems  to 
occur  year  by  year.  The  comparatively  recent  introduction 
of  electricity  in  its  multitudinous  forms  of  commercial  use,  and 
the  wide-spread  use  of  electric  and  gasolene  automobiles  may  be 
cited  as  examples  of  causes  tending  to  increase  the  fire  risk. 

Taking  the  city  of  Boston  as  a  representative  American  city, 
differing  little  from  our  other  large  cities  in  its  experiences,  we 
find  from  the  official  yearly  reports  of  the  Boston  Protective 
Department  that,  in  1881,  the  total  number  of  fire  alarms  in 
Boston  was  558,  in  1890  it  was  933,  in  1900  it  was  1779,  while 
in  1909  the  number  had  risen  to  2677  alarms,  not  including  still 
alarms. 

The  complete  statistics  for  alarms,  fires  involving  loss,  and 
total  losses  from  1881  to  1909  inclusive  will  be  found  on  the 
following  page. 

This  steady  increase  in  the  annual  number  of  fires  cannot  be 
accounted  for  on  the  basis  of  growth  of  population,  for,  while 
Boston  had  in  1880  a  population  of  362,000,  and  in  1900,  560,000, 
indicating  a  growth  in  the  interval  of  more  than  50  per  cent., 
the  total  number  of  alarms  of  which  the  fire  department  received 
notification  was  502  in  1882,  and  1985  in  1902,  showing  a  much 
greater  gain.  We  can  take  the  statistics  of  fires  at  which  losses 

*  For  a  very  able  and  interesting  discussion  of  fire  prevention  and  fire 
protection,  with  especial  reference  to  British  practice,  see  "What  is  Fire  Pro- 
tection?" by  Edwin  O.  Sachs,  publication  No.  1  of  the  British  Fire  Prevention 
Committee. 

24 


THEORY   AND    PRACTICE 


25 


Year. 

Total  alarms. 

Number  of  fires 
involving  loss. 

Total  loss. 

1881 

558 

344 

$  467,105.82 

1882 

502 

329 

958,835.88 

1883 

641 

371 

1,132,982.18 

1884 

633 

398 

1,101,253.60 

1885 

655 

397 

1,232,255.05 

1886 

687 

448 

1,089,196.05 

1887 

754 

460 

690,454.11 

1888 

834 

554 

1,031,676.72 

1889 

788 

494 

4,819,446.67 

1890 

933 

562 

1,088,887.29 

1891 

1012 

606 

1,511,674.51 

1892 

1196 

715 

846,595.12 

1893 

1233 

684 

5,024,765.04 

1894 

1233 

714 

1,726,627.56 

1895 

1234 

719 

1,195,343.28 

1896 

1397 

813 

1,367,165.92 

1897 

1435 

957 

861,203.64 

1898 

1499 

967 

1,415,884.93 

1899 

1768 

1108 

1,699,900.57 

1900 

1779 

1145 

1,674,776.44 

1901 

1681 

1045 

1,754,437.55 

1902 

1985 

1184 

1,570,533.25 

1903 

1990 

1140 

2,040,235.95 

1904 

2001 

1228 

2,491,706.43 

1905 

2320 

1337 

2,143,031.35 

1906 

*  3069 

1518  „ 

1,246,110.06 

1907 

*  4414 

2096 

2,296,525.10 

1908 

*  4502 

2234 

3,259,420.27 

1909 

*  4032 

1921 

2,248,335.03 

*  Including  still  alarms. 

occurred  for  a  series  of  years  about  twenty-five  years  ago,  and 
for  a  series  of  recent  years.  From  1881  to  1885,  inclusive,  the 
number  of  fires  that  occurred  in  Boston,  and  which  involved  loss, 
ran  from  329  to  398,  minimum  and  maximum  respectively.  But 
in  the  five  years  from  1905  to  1909  inclusive,  the  number  of  fires 
resulting  in  loss  ranged  from  1337  in  1905  to  2234  in  1908.  In 
other  words,  during  a  period  of  about  twenty-five  years,  while 
the  population  increased  about  68  per  cent.,  there  has  been  an 
increase  in  the  number  of  fires  involving  a  loss  of  almost  400  per 
cent.,  thus  showing  that  the  causes  of  fire  have  tremendously 
increased,  while  our  national  trait  of  carelessness  regarding  the 
fire  hazard  is  always  largely  responsible. 


26  FIRE   PREVENTION   AND   FIRE   PROTECTION 

Causes  of  Fire.  —  Taking  the  city  of  Boston,  again,  as  a 
representative  American  city,  and  following  the  statistics  given 
by  the  Boston  Protective  Department,  a  comparison  may  be 
made  concerning  the  variance  in  causes  of  fires  twenty-five 
years  ago,  and  now.  The  fire  record  of  the  year  1884  appears 
to  have  been  a  perfectly  normal  one  so  far  as  the  number  of 
fires  and  the  extent  of  losses  were  concerned,  but,  comparing 
the  causes  of  fires  in  that  year  with  the  statistics  for  1909,  a 
most  serious  increase  in  carelessness  on  the  part  of  the  inhab- 
itants is  evident.  In  1884,  78  of  the  fires  that  occurred  were 
due  to  matches  either  carelessly  used  by  children  or  found  and 
gnawed  by  rats  and  mice;  but  in  1909,  349  fires  with  loss  were 
due  to  the  same  cause  —  that  is,  the  number  of  fires  in  1909 
from  this  cause  was  almost  four  and  one-half  times  that  of 
twenty-five  years  before.  Seventy-eight  fires  also  occurred  in 
1884  from  sparks  emitted  from  chimneys,  etc.,  and  from  defective 
or  overheated  chimneys  or  heating  and  cooking  apparatus,  while 
in  1909,  234  fires  with  loss  originated  from  the  same  causes. 
Gas,  kerosene  oil,  and  candles  were  responsible  for  85  fires  in 
1884,  and  for  322  fires  with  loss  in  1909.  Considering  the  com- 
paratively recent  general  introduction  of  electricity,  it  is  not  so 
strange  that  there  were  only  three  fires  in  1884  from  electrical 
causes,  as  against  27  in  1909. 

The  following  table  *  (pages  28  and  29)  gives  the  causes  of  fires 
in  detail  in  the  city  of  Boston  over  a  period  of  twenty-five  years. f 

Carelessness  as  Cause  of  Fires.  —  Assuming  that  hot  ashes 
in  wooden  receptacles,  defective  buildings,  the  careless  use  of 
fireworks,  gas,  kerosene  oil,  and  matches,  overheating,  sparks, 
and  attempting  to  thaw  water  pipes  by  flame  are  easily  pre- 
ventable, it  appears  from  the  above  table  that  no  less  than 
56.29  per  cent,  of  the  fires  in  Boston  in  this  twenty-five  year 
period  may  be  directly  attributed  to  carelessness. 

That  the  experience  of  Boston,  as  indicated  by  the  table  of 
causes  of  fires  and  the  analysis  of  same  is  not  peculiar,  is 
attested  by  the  following  abstract  from  the  1906  yearly  report 
of  Francis  J.  Lantry,  then  Fire  Commissioner  of  New  York  City. J 

*  See  Thirty-second  Annual  Report  of  Boston  Protective  Department. 

t  A  similar  seven-year  classification  of  the  causes  of  fires,  in  which  the  Con- 
tinental Insurance  Company  of  New  York  was  interested,  may  be  found  in 
Insurance  Engineering  for  April,  1906. 

t  See  1906  Report  of  New  York  City  Fire  Department. 


THEORY   AND    PRACTICE  27 

At  the  outset  I  regard  it  as  of  the  utmost  necessity  to  call 
public  attention  to  the  vast  number  of  fires  that  seem  to  be  caused 
only  by  utter  carelessness,  and  to  suggest  that  some  remedy  may 
be  adopted  that  will  in  a  measure  reduce  the  number  of  fires 
arising  from  this  cause.  No  one  can  carefully  read  the  figures 
contained  in  the  Fire  Marshal's  report  to  me  without  being 
astounded  at  the  number  of  fires  that  could  have  been  prevented 
by  the  exercise  of  very  ordinary  caution.  I  think  that,  if  the 
public  mind  is  sufficiently  aroused  for  the  proper  exercise  of  this 
caution,  the  people  generally  can  become  of  great  service  to  this 
Department  in  the  prevention  of  fires.  The  Fire  Marshal's 
Bureau  is  for  the  investigation  and  determination  of  the  causes 
of  fires,  and  the  head  of  that  Bureau  reports  that  in  the  boroughs 
of  Manhattan,  The  Bronx,  and  Richmond,  among  the  principal 
causes  of  fires  ascertained  by  his  investigation,  887  were  due  to 
carelessness  with  matches  and  228  due  to  children  playing  with 
matches  or  fire.  Carelessness  in  the  use  of  lighted  cigars  and 
cigarettes  caused  401  fires;  overheated  stoves,  stovepipes,  etc., 
are  charged  with  the  responsibility  for  419  fires;  bonfires,  brush 
fires,  etc.,  are  charged  with  282;  carelessness  with  candles, 
tapers,  etc.,  386;  gaslight  in  contact  with  curtains,  etc.,  216; 
lamps,  kerosene,  etc.,  upsetting  or  exploding,  161.  *  Causes  of 
fires  not  positively  ascertained,  2764,'  writes  the  Fire  Marshal, 
who  adds:  'Many  of  these  were  probably  due  to  carelessness 
with  matches  or  with  lighted  cigar  or  cigarette  butts/ 

The  Fire  Marshal,  boroughs  of  Brooklyn  and  Queens, 
reports  that  732  fires  were  caused  by  matches  igniting  awnings, 
bedding,  clothing,  rubbish,  straw,  etc.,  and  in  his  report  will  be 
found  many  other  instances  of  fires  caused  by  carelessness. 

This  record  of  carelessness  of  life  and  property  is  one  that 
must  demand  attention,  and  1  regard  its  correction  as  a  matter 
that  would  largely  profit  the  people,  as  well  as  one  that  would 
immeasurably  assist  this  Department.  I  believe  that  every 
City  Department  which  has  officers  or  inspectors  constantly 
coming  in  touch  with  the  people  should  take  cognizance  of  this 
condition  of  things  through  their  officers  or  inspectors  calling  the 
attention  of  the  householder  to  the  dangers  arising  from  care- 
lessness as  indicated  in  this  report. 

The  fires  in  New  York  City  in  1906,  the  year  to  which  the  above 
report  especially  applied,  numbered  12,182.  If  our  large  cities 
were  to  adopt  some  such  regulations  as  are  in  force  in  London, 
England,  where  a  needless  fire  alarm  or  a  chimney  fire  subjects 
the  individual  or  property  owner  to  a  stipulated  cash  fine,  great 
improvement  would  undoubtedly  soon  be  apparent,  both  in  the 
number  of  fire  alarms  and  in  the  causes  of  fires. 

Incendiarism.  —  All  towns,  cities,  and  states  should  enforce 
stringent  regulations  covering  inquiry  or  "fire  inquest  "  held  on 
the  spot,  in  the  event  of  suspicions  pointing  to  arson.  Such 


28 


FIRE    PEEVENTION    AND    FIRE   PROTECTION 


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30  FIRE   PREVENTION   AND   FIRE   PROTECTION 

inquiries  should  be  conducted  by  the  local  fire  and  police  de- 
partment officials,  or  preferably  through  the  institution  of  state 
fire  marshal  offices,  such  as  are  now  in  force  in  many  states. 
For  a  detailed  account  of  state  fire  marshal  offices,  see  address 
on  Fire  Marshal  Laws,  by  Dr.  Clarence  Maris,  Assistant  Fire 
Marshal  of  Ohio,  in  the  1909  Proceedings  of  the  National  Fire 
Protection  Association,  from  which  paper  the  following  is  taken : 

Every  fire  marshal  is  effective  in  proportion  to  the  money 
he  has  to  spend. 

To  be  successful  in  securing  convictions  for  burning  to 
defraud,  the  fire  marshal  must,  by  bulletins  to  the  country  news- 
papers, show  the  people  from  among  whom  jurors  are  drawn 
that  when  a  building  burns,  money  from  insured  neighbors  pays 
the  loss. 

In  Ohio,  the  state  in  which  the  fire  marshal  is  most  gen- 
erously supported  and  bulletins  have  been  used  longest,  there 
were  more  convictions  for  incendiarism  in  two  and  a  half  years 
than  in  the  century  preceding  the  establishing  of  the  department. 

In  spite  of  the  fact  that  a  tax  of  one-half  of  one  per  cent, 
is  levied  on  gross  premiums,  in  spite  of  the  fact  that  the  farm 
mutuals  now  carry  300,000  risks,  all  preferred,  the  premium 
rate  in  Ohio  is  lower  than  in  any  one  of  the  five  states  adjoin- 
ing it. 

Common  Hazards.  —  It  has  previously  been  shown  that 
common  hazards  only  too  frequently  mean  simple  carelessness. 
Over  and  above  the  personal  element  of  carelessness,  however, 
many  common  hazards  are  susceptible  of  vast  improvement  in 
their  prevention. 

Thus,  the  so-called  parlor  match  should  be  everywhere  pro- 
hibited by  law;  safety  matches,  which  can  only  be  ignited  by 
striking  on  the  box  cover,  are  far  safer  in  the  hands  of  children 
or  irresponsibles;  the  heads  do  not  fly  off,  as  is  so  apt  to  be  the 
case  with  the  parlor  match,  and  they  do  not  ignite  when  trod- 
den on. 

City  ordinances  should  require,  and  enforce  in  so  far  as  may 
be  practicable,  the  use  of  metal  ash  cans  for  the  receipt  of  stove 
or  furnace  ashes.  The  depositing  of  hot  ashes  in  wooden  recep- 
tacles is  responsible  for  many  fires  in  every  large  city. 

Another  contributary  cause  of  many  fires  is  defective  flues, 
principally  in  dwellings.  This  subject  is  discussed  more  at 
length  in  Chapter  XXIV. 

Special  Hazards.  —  These  include  such  fire  dangers  as 
lightning,  fireworks,  and  other  explosives,  petroleum,  gasolene, 


THEORY   AND   PRACTICE  31 

etc.  (for  which  see  Chapter  XXVIII),  and  the  special  hazards 
incident  to  various  manufacturing  operations  (for  which  see 
paragraphs  Character  of  Building  and -Isolation  of  Mechanical 
Plants  and  Special  Risks  in  Chapter  IX). 

Educational  Measures.  —  Following  the  suggestion  of  Mr. 
C.  M.  Goddard,  former  president  of  the  National  Fire  Pro- 
tection Association,  that  society  inaugurated,  at  its  1909  annual 
meeting,  the  appropriation  of  funds  for  the  active  prosecution 
of  a  campaign  of  publicity,  to  be  conducted  through  its  members 
and  through  the  daily  press,  etc.  Lecturers,  speakers,  and  timely 
news  articles  pertaining  to  fire  prevention  and  fire  protection 
are  furnished  by  the  association,  in  an  endeavor  to  improve 
public  sentiment  in  regard  to  these  vital  questions.  The  move- 
ment has  but  started,  and  much  yet  remains  to  be  done.  Similar 
educational  work  is  being  undertaken  in  great  Britain  by  the 
British  Fire  Prevention  Committee. 

The  idea  of  interesting  school  children  in  such  subjects  opens 
up  great  possibilities. 

I  believe  that  it  would  be  a  good  idea  if  the  board  of  edu- 
cation was  asked  to  give  directions  to  school  principals  and 
teachers  that  would  result  in  instructions  being  given  to  the 
children  of  our  public  schools  of  the  dangers  arising  from  what 
may  apparently  seem  to  be  trifling  carelessness,  and  yet  may  be 
productive  of  great  loss.  It  seems  to  me  that,  if  the  warning 
against  fire-causing  carelessness  is  properly  disseminated  among 
the  scholars  in  the  public  schools,  it  will  have  a  lasting  effect, 
and  it  will  not  only  be  beneficial  at  an  early  day,  but  for  years 
to  come,  so  that  the  necessity  for  caution  will  be  deeply  im- 
pressed upon  the  minds  of  the  children  and  will  remain  with 
them  as  they  grow  to  be  men  and  women.* 

A  law  is  now  upon  the  statute  books  of  phio  requiring  text- 
books to  be  read  in  the  schools  of  that  state  on  the  "  Dangers 
and  Chemistry  of  Fires."  Similar  laws  have  been  enacted  by 
the  states  of  Montana,  Nebraska,  and  Iowa. 

Building  Laws  and  Other  Regulations.  —  It  is  to  be  hoped 
that  the  crusades  of  education  undertaken  by  the  National  Fire 
Protection  Association,  the  National  Board  of  Fire  Under- 
writers, and  other  organizations,  will,  in  due  course  of  time,  so 
stimulate  general  public  sentiment  along  the  line  of  fire  pre- 
ventive measures  as  to  demand  governmental  and  state  legis- 

*  From  1966  Report  of  New  York  Fire  Department,  Francis  J.  Lantry 
Commissioner. 


32  FIRE    PREVENTION   AND    FIRE   PROTECTION 

lation  looking  to  the  improvement  of  present  conditions.  It  has 
been  shown  in  Chapter  I  how  European  nations  control  the  fire 
hazard  through  both  national  regulations  and  local  supervisions 
of  a  most  rigid  character.  With  us,  the  reverse  is  distinctly 
true.  Not  only  are  there  no  governmental  restrictions,  but  state 
laws  governing  building  construction  and  fire  prevention  and 
fire  protection  show  no  uniformity  whatever,  varying  from 
practically  no  regulations  to  only  indifferently  good  ones.  The 
same  variance  exists  in  our  local  or  city  laws.  Many  matters 
wrhich,  in  Europe,  are  rigidly  controlled,  with  us  are  not  demanded 
of  the  individual,  provided  he  cares  to  assume  the  risk  to  himself 
and  neighbors  by  foregoing  insurance  or  by  paying  added  pre- 
mium rates,  or  by  paying  the  rates  demanded  and  passing  on 
the  risk  to  the  community. 

A  good  example  of  the  lack  of  governmental  supervision  is 
seen  in  the  absence  of  laws  concerning  such  buildings  as  summer 
hotels,  town  halls,  asylums,  schools,  etc.  Most  state  laws  are 
so  lax  in  regard  to  such  buildings  that  almost  any  construction 
is  permitted  outside  of  city  limits.  Structures  of  this  character, 
housing  many  adults  or  children,  should,  through  the  coopera- 
tion of  government  with  the  several  states,  be  rigidly  controlled 
as  to  construction  and  equipment. 

An  example  of  the  laxity  of  usual  city  regulations  is  to  be 
found  in  the  laws  governing  factories,  as  is  pointed  out  in  more 
detail  in  Chapter  XXV. 

On  the  other  hand,  city  building  laws  are  often  too  specific 
and  too  voluminous,  proving  too  rigid  for  some  cases.  Many 
points  of  practice,  after  certain  broad  and  fundamental  require- 
ments are  laid  down,  are  best  left  to  the  discretion  of  the  proper 
authorities  as  occasion  is  raised,  but  such  officials  have  need  of  a 
far  different  conception  of  public  duty  from  that  exhibited  in 
the  political  domination  of  usual  city  building  departments. 

A  satisfactory  building  law  for  city  use  is  to  be  found  in  the 
"  Building  Code  "  recommended  by  the  National  Board  of  Fire 
Underwriters,  extracts  from  which  are  given  in  various  following 
chapters.  The  following  " foreword"  accompanying  the  Code 
illustrates  its  applicability: 

In  the  belief  that  safe  and  good  construction  of  buildings 
should  be  universally  recognized  as  of  the  utmost  importance, 
this  building  code,  prepared  and  recommended  by  the  under- 
signed committee,  is  based  on  broad  principles  which  have  been 


THEORY   AND   PRACTICE  33 

sufficiently  amplified  to  provide  for  varying  local  conditions  in 
towns  as  well  as  in  cities. 

The  benefits  to  be  derived  from  uniform  building  laws 
throughout  the  country  lead  the  committee  to  urge  the  adoption 
of  this  code  in  its  entirety.  In  small  towns  or  cities  where  there 
is  no  department  of  buildings,  it  might  be  enforced  through  a 
Bureau  of  Buildings  under  the  jurisdiction  of  the  Fire  Depart- 
ment, the  words:  'Commissioner  of  Buildings'  being  changed 
to  'Superintendent'  or  'Inspector  of  Buildings.'  In  like  man- 
ner other  provisions  may  be  changed  to  meet  local  requirements, 
at  the  same  time  maintaining  essential  recommendations. 

This  code  has  been  distributed  free,  by  the  National  Board, 
to  all  municipalities  in  the  United  States  having  a  population  of 
5000  or  over.  It  has  been  adopted  in  full  by  Jersey  City,  N.  J., 
and  Charleston,  S.  C.,  and  in  part  by  many  other  cities.  Con- 
siderably over  100  cities  have  taken  up  the  question  of  new 
building  laws  during  recent  years,  largely  through  the  stimu- 
lation of  the  work  of  the  National  Board. 

Fire  Protection  Defined.  —  Fire  protection,  as  applied  to 
buildings,  includes  control  of  fire  through  construction,  control 
by  means  of  first  aid  or  departmental  work,  detection  of  fire  by 
automatic  means,  and  safety  against  exposure  hazard. 

Control  by  Construction.  —  The  best  possible  illustration 
of  control  by  construction  is  furnished  by  those  instances  where 
fire  has  been  confined,  absolutely,  to  the  compartment  or  unit 
of  area  within  which  it  originated,  and  this  without  the  knowl- 
edge of  tenants  or  others.  Such  cases,  while  comparatively 
rare,  are  by  no  means  unheard  of,  as  several  fires  in  office  build- 
ings, hotels,  and  warehouses  testify,  in  which  fire  has  completely 
destroyed  the  contents  of  a  room,  died  out  for  want  of  fuel,  and 
only  been  discovered  at  some  later  period. 

Fire-resisting  construction  should  always  be  planned  and 
carried  out  to  approximate  this  ideal  as  nearly  as  may  be  pos- 
sible, and  parts  II,  III,  IV,  and  V  of  this  volume  are  intended 
to  show  how  this  may  be  accomplished  as  far  as  materials, 
planning,  and  details  of  construction  are  concerned. 

We  are  very  apt  to  picture  such  a  structure  in  the  mind's  eye 
as  a  massive,  uninteresting,  and  inartistic  pile  of  brick,  terra- 
cotta, or  concrete,  with  solid  masonry  partition  walls,  tin-  or 
metal-covered  doors  and  window  shutters,  —  in  short,  a  struc- 
ture wherein  all  thoughts  of  beauty  or  architectural  expression 
have  had  to  be  subordinated  to  considerations  of  purely  struc- 
tural and  practical  value. 


34  FIRE   PREVENTION   AND   FIRE   PROTECTION 

But  such  is  not  the  case,  at  least  in  any  such  extreme  sense. 
The  ingenuity  of  the  architect,  coupled  with  the  endeavors  of 
progressive  contractors  and  manufacturers,  have  succeeded  in 
solving,  at  least  in  part,  the  problem  of  making  many  details 
of  fire-resisting  design  attractive  and  ornamental,  as  well  as 
efficient.  This  transition  has  been  progressing  ever  since  the 
modern  type  of  so-called  fireproof  building  became  an  established 
fact,  but  especial  progress  has  been  made  since  the  Baltimore 
fire.  Experience  gained  .in  that  catastrophe  has  served  as  a 
wonderful  educator  to  investors,  insurance  interests,  and  those 
entrusted  with  building  design  and  construction,  as  well  as  a 
powerful  object  lesson  to  the  manufacturer  of  building  materials 
and  devices. 

Control  by  First  Aid  or  Fire  Department.  —  The  control  of 
fire  through  the  employment  of  first  aids,  such  as  water  buckets, 
extinguishers,  etc.,  is  treated  of  in  Chapter  XXXII,  while  fire- 
department  operations,  with  especial  reference  to  equipment  or 
protective  devices,  are  considered  in  Chapter  XXIX. 

Automatic  Detection  of  Fire.  —  Over  and  above  human 
'agency,  fire  may  be  detected  through  the  means  of  thermostats 
or  automatic  alarms,  as  described  in  Chapter  XXXI,  or,  fire 
may  be  detected,  and  partially  or  fully  controlled,  through  the 
use  of  automatic  sprinklers,  as  described  in  Chapter  XXX. 

Exposure  Hazard.  —  Safety  against  exposure  hazard  in- 
volves: 1,  protective  measures  against  an  immediately  adjacent 
risk,  which  hazard  is  always  considered  in  the  insurance  rate 
and  charged  for  according  to  the  imminence  of  the  risk  and 
the  protective  features  adopted,  and,  2,  protection  against  an 
extended  conflagration.  The  hazard  of  the  latter  possibility 
depends  largely  upon  how  well  immediate  exposures  are  met. 

The  possible  causes  of  exposure  fires  are  thus  summarized  by 
Mr.  Everett  U.  Crosby.* 

Exposure  and  conflagration  possibilities  from  grouped  risks 
are  due  to  fire  extending  from  one  building  to  others  in  view 
of  the  following  cases:  (a)  fire  in  the  individual  risk  passing 
beyond  control;  (6)  effect  of  the  size  of  the  risk,  viz.,  the  quantity 
of  combustible  comprising  the  building  and  contents  subject  to 
burning  at  one  time;  (c)  fire  extending  out  through  wall  openings 
and  through  roofs;  (d)  fire  entering  through  wall  openings  and 
through  roofs;  (e)  fire  spreading,  due  to  the  falling  of  burning 
rooms,  floors,  and  contents;  (/)  fire  spreading  due  to  falling  walls 

*  See  "Exposure  Fires  Analyzed,"  Insurance  Engineering,  June,  1905. 


THEORY   AND   PRACTICE  35 

of  a  burning  building;  (g)  influence  of  street  widths  and  open 
areas;  (h)  influence  of  prevailing  winds;  (i)  the  'range'  of  or 
territory  affected  by  heat  waves  and  fire  brands;  (j)  adverse 
conditions  of  the  weather  or  of  the  fire  facilities  at  time  of  fire. 

Most  of  these  questions  are  considered  in  succeeding  chapters. 
Courses  of  Instruction  in  Fire  Protection.  —  That  the 

theory  and  practice  of  fire  prevention  and  fire  protection  are 
recognized  as  a  scientific  specialty,  worthy  a  broad  and  com- 
prehensive course  of  study,  is  indicated  by  the  special  course 
of  instruction  in  these  subjects  offered  by  the  Armour  Institute 
of  Technology,  Chicago,  111.  The  course  in  Fire  Protection 
Engineering  was  started  in  1903. 

The  curriculum,  which  extends  over  four  years,  includes 
fundamental  subjects,  such  as  mathematics,  physics,  electricity, 
and  applied  mechanics,  which  are  necessary  as  a  foundation  for 
any  engineering  training.  Particular  attention  is  given  to  the 
study  of  industrial  and  engineering  chemistry,  and  a  series  of 
thorough  courses  in  these  subjects  extends  throughout  the  first 
three  years.  The  purely  professional  work  of  the  department 
is  given  in  the  third  and  fourth  years  and  begins  with  a  careful 
study  of  types  of  building  construction  and  general  practice  in 
the  application  of  protective  measures.  A  critical  examination 
is  made  of  Underwriters'  Requirements,  and  those  pertaining 
to  field  work  are  illustrated  by  field  inspections  conducted  by  a 
competent  instructor  experienced  in  inspection  work.  A  study 
is  made  of  the  various  rating  schedules  in  use  in  different  parts 
of  the  country  and  practical  application  of  these  schedules  is 
made  to  the  mercantile,  manufacturing,  and  special  hazard  risks 
for  which  they  are  designed.  The  work  is  extended  to  cover 
buildings  in  course  of  construction  as  well  as  finished  and  occu- 
pied premises,  and  includes  attention  to  faults  of  design,  struc- 
tural defects,  installation,  and  maintenance  of  fire  stops  and 
protective  equipment. 

The  laboratory  work  of  the  department  is  carried  through 
the  junior  and  senior  years  of  the  course  and  is  supplemented 
from  time  to  time  by  outside  tests  of  steam  and  electric-pumping 
machinery  and  other  apparatus  embodied  in  private  equipments. 
Thus  the  student  is  familiarized  with  correct  and  faulty  con- 
struction and  installation  of  hazardous  and  protective  equipment 
and  apparatus.  The  work  is  planned  to  include  demonstration 
of  practical  test  methods  for  use  in  the  field,  laboratory,  and  shop. 
The  students  frequently  witness  the  fire-tests  made  at  the  Under- 
writers' Laboratories,  and  they  also  have  the  privilege  at  times 
"  using  that  testing  plant  for  laboratory  tests. 


Lecture  courses  on  fire  protection  are  given  at  Harvard  Uni- 
versity, the  Stevens  Institute  of  Technology,  and  at  some  other 


36  FIRE   PREVENTION   AND   FIRE   PROTECTION 

colleges.  A  one-year  evening  course  in  fire  protection  and  fire 
insurance  is  given  at  the  New  York  University,  while  an  evening 
lecture  course  on  the  same  subjects  is  offered  at  Columbia 
University,  New  York. 

Fire  Protection  Library.  —  Mr.  Henry  E.  Hess,  Manager 
of  the  New  York  Fire  Insurance  Exchange,  in  an  address*  en- 
titled "The  Making  of  a  Fire-insurance  Library/'  stated  "In 
the  absence  of  a  complete  library,  I  have  often  been  asked  to 
"name  the  books  that  would  cover  a  good  course  of  reading  in 
fire  insurance,  or  that  would  represent  a  compact  but  fairly 
comprehensive  library  for  an  individual  to  own.  I  have  pre- 
pared such  a  list,  and  for  such  collateral  interest  as  it  may  have 
in  connection  with  the  main  topic  of  this  paper,  I  here  submit 
it,  premising  that  it  may  be  reduced  by  leaving  out  the  law  books, 
if  one  is  not  interested  in  that  side  of  the  subject. 

A.  Upon  Fire  Insurance  generally: 

1.  The  Principles  and  Finance  of  Fire  Insurance;  F.  H. 

Kit  chin. 

2.  Yale  Insurance  Lectures  —  Fire  and  Marine. 

B.  Upon  the  Construction  of  Buildings: 

1.  Fire  Insurance  and  How  to  Build;   F.  C.  Moore. 

2.  Building  Construction  for  Beginners;    J.  W.  Riley. 

3.  Building  Instruction  and  Superintendence;    F.   E. 

Kidder  (Part  II,  Carpenter  Work). 

4.  The  Fireproofing  of  Steel  Buildings;    J.  K.  Freitag. 

5.  Reinforced  Concrete;   C.  F.  Marsh. 

C.  Upon  the  Hazards  of  Contents  of  Buildings: 

1.  The  Chemistry  of  Fire  Prevention;   H.  Ingle. 

2.  Fire  and  Explosion  Risks;   Dr.  Von  Schwartz. 

3.  The  Journal  of  the  Federation  of  Insurance  Insti- 

tutes   of    Great   Britain    and  Ireland;    published 
annually. 

4.  Quarterly  Bulletin  of  the  National  Fire-protection 

Association. 

D.  Upon  the  Making  of  Rates: 

1.  The  Universal  Mercantile  Schedule;    F.  C.  Moore. 

2.  Fire  Rating  as  a  Science;   A.  F.  Dean. 

E.  Upon  the  Law  of  Fire  Insurance: 

1.  Law  of  Insurance  Agency;    Wolff. 

2.  Richards  on  Insurance;  Fire,  Life,  Marine;  1  volume. 

3.  Joyce  on  Insurance;  4  volumes  (covering  ail  branches 

of  insurance  and  bringing  law  decisions  down  to 
1903). 

4.  Finch's  Digest;  published  annually. 

*  Read  before  the  thirty-seventh  annual  meeting  of  the  Fire  Underwriters 
Association  of  the  Northwest,  Chicago,  October,  1906. 


THEORY    AND    PRACTICE  37 

To  the  above  list  of  books  in  classification  B,  the  writer  would 
recommend  adding  a  number  of  valuable  reports  dealing  with 
tests  of  materials  and  building  construction,  etc.,  especially 
those  issued  by  the  United  States  Geological  Survey  referred  to 
elsewhere. 


CHAPTER  III. 
THEORY  AND  PRACTICE  OF  FIRE  INSURANCE. 

Origin  of  Fire  Insurance  in  United  States.  — While  insur- 
ance against  marine  losses  was  practiced  by  the  ancient  Greeks 
and  other  maritime  nations,  fire  insurance  can  be  reckoned  from 
the  organization  of  the  Amicable  Contributors,  which  took  place 
in  1696,  after  the  great  London  fire,  and  which  was  deduced 
from  the  earlier  Friendly  Society.  This  organization  was  oper- 
ated on  the  plan  of  our  present  mutual  companies,  its  members 
obligating  themselves  to  contribute  a  proportionate  share  of 
any  loss  sustained  by  other  members.  .  .  . 

In  America,  the  Philadelphia  Contributionship,  for  the  in- 
surance of  houses  against  loss  by  fire,  was  organized  in  1752. 
This  company  was  based  on  the  rules  and  rates  of  the  Amicable 
Contributors,  or  Hand-in-Hand,  and,  like  that  organization, 
the  clasped  hands  are,  up  to  the  present  day,  the  symbol  of  this 
society. 

At  a  general  meeting  of  the  Contributionship,  held  in  1781, 
the  question  of  the  hazard  of  shade  trees  in  front  of  houses 
was  discussed,  resulting  in  the  rule  that  no  houses  having  a 
tree  or  trees  planted  before  them  should  be  insured  or  reinsured. 
This  action  resulted  in  the  organization  of  the  Mutual  Assur- 
ance Company,  for  the  insurance  of  houses  from  loss  by  fire,  in 
1786.  This  aew  company  at  once  chose  the  symbol  of  a  green 
tree/ and  up  to  this  day  a  small  wooden  shield  with  a  green  tree 
pointed  thereon,  or  a  cast-metal  green  tree,  may  be  found  at- 
tached to  the  older  Philadelphia  dwelling.  The  new  company 
soon  became  known  as  the  '  Green  Tree/  and  is  still  so  called. 

The  Mutual  Assurance  Company  of  New  York  was  organ- 
ized in  1787.  In  1794  the  directors  of  the  Insurance  Company 
of  North  America,  which  company  had  been  operating  as  a 
marine  insurance  company  for  a  number  of  years,  considered 
the  question  of  also  assuming  the  insurance  of  houses,  and 
'  upon  goods,  wares  and  merchandise,  or  other  personal  prop- 
erty.' This  form  of  policy  was  finally  adopted  in  the  latter 
part  of  1794. 

The  Philadelphia  Fire  Insurance  Company  was  organized 
in  1804;  the  American  Fire  Insurance  Company  in  1810.  Early 
in  1810  the  council  of  the  City  of  Philadelphia  considered 
a  proposition  to  the  end  that  the  city  assume  the  insuring  of 
property  against  loss  by  fire;  but  although  the  plan  was  sup- 
ported by  some  of  the  best  citizens,  it  failed  of  consummation. 
The  Fire  Insurance  Company  of  the  State  of  Pennsylvania,  the 

38 


THEORY  AND   PRACTICE   OF   FIRE   INSURANCE        39 

Insurance  Company  of  the  County  of  Philadelphia,  the  Fire 
Association,  the  Pennsylvania  Fire,  and  the  Franklin  Fire  In- 
surance Company,  all  were  organized  in  the  early  part  of  the 
nineteenth  century,  and  Philadelphia  may  well  be  called  the 
home  of  fire  insurance  in  America.  .  .  . 

In  1796  the  board  of  directors  of  the  Insurance  Company 
of  North  America  passed  a  resolution  to  the  effect  that  proposals 
for  insurance  should  be  received  from  property  owners  outside 
of  the  Hen-mile  limit/  thereby  inaugurating  the  system  of  fire- 
insurance  agencies  which,  at  the  present  time,  has  grown  to  be 
one  of  the  greatest  systems  of  commercial  value  and  necessity. 
The  fire  insurance  agent  throughout  the  United  States  must  be 
considered  an  important  factor  in  the  insurance  business.  Hold- 
ing the  commission  of  the  company  or  companies  he  represents, 
to  all  intents  and  purposes,  in  his  dealings  with  the  property 
holder  seeking  indemnity,  he  is  the  company.* 

Insurance  Agents.  —  It  is  the  business  of  the  fire  insurance 
agent  to  write  insurance  policies,  and,  what  is  usually  considered 
of  more  importance,  to  collect  the  premiums  on  same.  Such 
policies,  on  account  of  the  liability  assumed  by  the  writing  com- 
pany, are  usually  reported  by  the  agent,  before  issuance,  to  the 
home  office  of  the  company,  with  such  information  as  may  be 
required  by  the  company  as  to  the  character  of  the  risk  and  the 
moral  and  financial  standing  of  the  assured.  In  cities  or  terri- 
tories where  a  large  business  is  done,  general  agencies  are  often 
established,  in  which  case  the  local  agent  reports  to  the  general 
agent  for  approval  of  policies,  the  latter  only  reporting  to  the 
home  office  at  stated  intervals. 

Besides  the  local  agents,  there  are,  in  large  cities,  insurance* 
brokers  who,  like  the  local  agents,  are  paid  by  the  insurance  com- 
panies a  per  cent,  commission  on  the  premiums.  On  account  of 
the  considerable  detail  involved  in  the  proper  placing  of  risks 
at  equable  rates,  large  owners  or  trustees  of  property  usually 
place  the  issue  and  reissue  of  policies  in  the  hands  of  some 
brokerage  firm  of  recognized  standing. 

The  profit  or  loss  of  fire  insurance  writing  is  largely  dependent 
upon  the  ability  and  good  judgment  of  the  ''special  agent,"  for 
it  is  upon  this  representative  of  the  insurance  company  that 
responsibility  must  fall  for  the  general  conduct  and  supervision 
of  the  business  in  the  field.  He  must  possess  a  wide  knowledge 

*  See  "Fire  Insurance  Practices  in  the  United  States,"  a  paper  read  by 
Mr.  Charles  Hexamer  before  the  International  Fire  Prevention  Congress, 
London,  1903. 


40  FIRE   PREVENTION   AND   FIRE   PROTECTION 

of  risks,  manufacturing  and  other  hazards,  construction,  pro- 
tective measures  and  adjustment  of  losses,  besides  being  able 
to  direct  and  lead  his  agents,  and  to  gauge  the  moral  and  financial 
standing  of  his  assured. 

Insurance  Rates.  —  The  rate  of  premium  is  the  amount  of 
money  charged  by  the  insurer  for  each  $100  of  indemnity  prom- 
ised to  the  insured.  The  rate  is  made  on  $100  of  indemnity 
simply  to  provide  a  ready  method  of  computing  the  total  pre- 
mium on  the  total  amount  of  insurance  written.  The  rate, 
therefore,  becomes  the  measure  of  the  risk  carried  by  the  insurer. 
The  greater  the  risk  the  greater  the  rate,  and  conversely,  the 
less  the  risk  assumed,  the  less  the  rate  charged. 

The  rate  of  premium  or  price  charged  by  the  company  is 
not  based  upon  the  expectation  of  burning  of  a  particular  risk 
insured,  but  upon  the  number  of  risks  of  like  kind  which  would 
be  burned  or  damaged  out  of,  say,  a  thousand  in  any  single  year. 
At  the  rate  of  one  per  cent.,  for  illustration,  a  thousand  risks, 
each  insured  for  $1000,  would  yield  $10,000  in  premiums.  If 
ten  risks  out  of  the  thousand  should  burn  in  a  year,  the  entire 
amount  of  premiums  would  be  required  to  pay  the  loss.  It  is 
evident  that  a  smaller  number  than  ten  must  burn,  or  a  higher 
rate  than  one  per  cent,  must  be  obtained  to  provide  for  expenses 
as  well  as  losses.* 

Methods  of  Rating.  —  Early  methods  of  underwriting  were 
based  on  very  crude  principles.  Buildings,  or  risks  as  they  are 
called  by  insurance  interests,  were  simply  classified  according 
to  occupancy,  and,  in  a  very  limited  way,  according  to  con- 
struction. Thus  rates  were  determined  for  specified  classifica- 
tions of  occupancy,  based  upon  brick  buildings,  and  all  brick 
buildings  containing  a  like  occupancy  were  subject  to  the  same 
class  rate.  If  the  risk  was  a  wooden  building,  a  specified  advance 
on  the  rate  was  charged.  In  other  words,  there  was  little  or  no 
distinction  made  between  risks  of  the  same  class.  This  system 
of  rating  was  essentially  defective  in  that  no  provision  was  made 
for  differentiating  between  varying  risks  in  the  same  class,  and 
as  it  became  more  and  more  apparent  that  defects  in  construc- 
tion and  protection  should  be  charged  for  through  added  pre- 
mium rates,  the  system  of  schedule  rating  was  devised. 

Schedule  rating,  which  is  now  commonly  followed  throughout 
the  United  States,  consists  of  class  rating  plus  individual  rating, 

*  "The  Relation  of  Fire  Insurance  to  the  Community,"  by  F.  C.  Moore 
and  Committee. 


THEORY   AND    PRACTICE   OF   FIRE    INSURANCE        41 

"the  class  rate  representing  the  class  of  the  risk,  and  the  items 
of  the  schedule  representing  the  individual  risk  of  the  class." 
By  this  method,  each  deviation  from  established  standards  is 
charged  for  separately  by  addition  to  the  premium  rate,  and 
conversely  lowered  by  improvements  in  construction  or  pro- 
tection, so  that  the  owner  of  the  property,  through  such  charges 
or  rebates,  will  feel  directly  the  defects  or  the  safeguards  exist- 
ing in  his  property. 

Schedules  in  common  use  include  the  Universal  Mercantile 
Schedule,  and  those  based  on  it,  Manufacturing  Schedules  and 
the  Dean  Schedules. 

These  schedules  vary  more  or  less  in  their  method  of  operation, 
but  essentially  they  are  similar,  since  they  are  all  based  on  the 
principle  of  discrimination  between  individual  risks  by  a  system 
of  itemized  ratings. 

A  properly  drawn  rating  schedule  is  a  convenient  and 
effective  expression  of  the  views  of  underwriters  at  large  upon 
standards  in  materials,  construction  and  protection,  and  is,  there- 
fore, a  guide  to  architects  and  builders  who  desire  to  follow 
the  best  methods  of  fire  prevention.  It  is  also  educational  to 
the  public,  and  has  frequently  to  my  knowledge  influenced  the 
adoption  of  better  building  laws,  following  the  principles  laid 
down  in  the  schedule.  It  seems,  therefore,  that  such  a  system 
should  be  considered  a  most  important  ally,  and  almost  indis- 
pensable to  the  other  and,  perhaps,  better  known  branches  of 
scientific  fire  prevention,  representing  as  it  must  the  best  thought 
of  all  who  are  interested  in  that  subject,  whatever  may  be  their 
profession.* 

The  "Universal  Mercantile  Schedule/' —  The  first  really 
scientific  schedule  was  prepared  and  published  under  the  above 
title  by  Mr.  Francis  C.  Moore,  then  president  of  the  Continental 
Fire  Insurance  Company  of  New  York.  As  its  name  implies, 
the  " Universal  Schedule"  is  intended  for  universal  use  in  estab- 
lishing rates  of  insurance  for  mercantile  buildings  and  their 
contents,  being  adaptable  to  any  locality.  The  following  brief 
description  of  this  schedule  is  taken  from  the  previously  quoted 
address  by  Mr.  Wilmerding: 

A  standard  for  a  city  is  first  established,  that  is,  in  rela- 
tion to  its  water  supply,  municipal  fire  department,  width  of 
streets  and  general  construction  with  reference  to  conflagration 

*  See  "Fire  Prevention  through  Schedule  Rating,"  by  H.  Wilmerding, 
Secretary  Philadelphia  Fire  Underwriters'  Association,  1903  International  Fire 
Prevention  Congress. 


42  FIRE   PREVENTION   AND   FIRE   PROTECTION 

hazard.  Then  a  standard  type  of  building  is  prescribed,  includ- 
ing such  individual  fire  protection  as  should  be  installed.  With 
these  two  standards  established,  a  basis  or  key  rate  for  a  stand- 
ard building  in  a  standard  city  is  determined  upon.  This  basis 
or  key  rate  is,  in  a  general  way,  indicative  of  the  experience  of 
the  fire  loss  on  such  a  building  in  the  country  under 'consider- 
ation, and  I  would  here  call  attention  to  the  value  of  properly 
collated  statistics  in  determining  what  such  basis  rate  should  be. 
Please  also  note  the  value  of  the  tests  and  standards  of  the 
British  Fire  Prevention  Committee,  the  National  Fire  Protec- 
tion Association  of  the  United  States  and  sister  organizations, 
in  establishing  the  standards  for  water  supply,  fire  departments, 
construction  and  protection  of  buildings;  and  note  the  power  of 
the  underwriter  to  force  the  adoption  of  such  standards  by  in- 
creasing the  rate  of  premium  for  deviations  therefrom,  which 
course  is  fully  warranted  because  such  deviations  must  in  the 
end  inevitably  result  in  increased  losses  for  the  insurance  com- 
panies. As  a  city,  therefore,  approaches  or  departs  from  the 
standards  laid  down  for  a  city,  so  will  the  basis  rate  for  a  stand- 
ard building  in  that  city  be  smaller  or  greater. 

To  whatever  basis  rate  is  so  found  are  added  charges  for 
deficiencies  from  standards  of  construction  for  each  building. 
The  features  considered,  and  for  which  graded  charges  are 
established,  embrace  the  quality  and  thickness  of  walls;  height 
of  parapet  above  roof;  character  and  material  of  roof;  blind 
attics  and  concealed  spaces;  thickness  of  floors  and  supporting 
beams  or  joists;  ceilings  or  side  walls  sheathed  with  combustible 
materials;  area  of  ground  floor;  height  of  building;  openings  in 
floors  for  elevators,  stairways,  well  holes,  dumb-waiters,  etc. 
and  their  protection;  skylights  of  thin  glass  with  wood  frames; 
wood  cornices,  cupolas,  dormer  windows,  awnings,  etc.;  methods 
of  lighting  and  heating;  construction  of  chimneys ;  condition  and 
width  of  street  on  which  building  stands;  overhead  telegraph 
and  other  wires  to  interfere  with  operations  of  fire  department; 
number  of  tenants;  age  of  building  and  its  condition;  wooden 
additions  and  extensions  to  building;  stone  or  unprotected  iron 
columns,  or  brick  piers  with  bond  stones  if  carrying  important 
loads,  etc.  When  the  sum  of  these  deficiency  charges  is  added 
to  the  basis  rate,  we  arrive  at  a  rate  for  the  building  unoccupied 
and  without  individual  fire  protection. 

A  charge  is  then  made  for  any  additional  hazard  caused 
by  the  occupancy  of  the  building.  This  charge  has  already 
been  established  for  about  thirteen  hundred  different  occupan- 
cies, and  the  different  occupancy  charges  are  carefully  graded 
according  to  the  ignitibility,  combustibility  and  susceptibility 
of  the  merchandise.  I  would  again  point  out  the  close  relation 
of  this  charge  to  classification  statistics. 

The  occupied  building  rate  is  then  subject  to  prescribed 
percentage  deductions  for  different  features  of  protection  which 
may  be  incidental  to  each  building,  such  as  proximity  to  public 
hydrants  and  size  of  street  water-mains;  automatic  fire  alarm  in 


THEORY  AND   PRACTICE   OF   FIRE   INSURANCE       43 

building;  chemical  fire  engines  available;  fire  escapes;  casks  of 
water  and  fire  buckets;  internal  and  external  standpipes,  with 
adequate  water  pressure  and  sufficient  hose  of  standard  size  and 
quality;  accessibility  of  the  building  to  the  fire  department,  and 
its  proximity  to  fire  engine  house,  etc.;  basement  and  sub- 
cellar  sprinklers,  whether  automatic  or  controlled  by  hand 
valve;  occupancy  of  the  building  by  one  or  more  families  for 
dwelling  purposes  above  the  grade  floor,  or  office  occupancy; 
private  watchman,  with  or  without  watchman's  clock;  roof 
hydrants  with  adequate  water  pressure  and  sufficient  hose  of 
standard  size  and  quality;  floor  beams  and  girders  so  arranged 
as  to  be  self-releasing  from  walls  when  burned  through,  thus 
relieving  the  walls  of  the  strain  from  the  otherwise  unsupported 
beams  or  girders;  unusual  number  of  fire  engines  available  at 
any  fire  on  account  of  favourable  location  of  building  ;  water 
tower  or  fire  boats  available  at  any  fire  in  building;  number  of 
effective  fire  streams  available  with  adequate  gravity  pressure; 
full  equipment  of  automatic  sprinklers,  etc.  These  percentage 
deductions  for  standard  equipments  answer  the  same  purpose  as 
charges  for  deficiencies  from  standards,  credit  for  protective 
features  being  given  in  that  form  on  the  theory  that  the  added 
fire  protection  reduces  the  hazard  of  each  item  which  goes  to 
make  up  the  building  rate  by  an  equal  proportion,  and  of  course, 
where  standards  have  been  established  for  protective  devices, 
deviations  from  such  standards  are  taken  care  of  .by  reduced  per- 
centage allowances,  or  no  allowance  at  all,  as  each  case  merits. 

Finally,  there  is  added  to  the  rate  at  this  point  whatever 
is  necessary  to  cover  the  hazard  from  exposures  without,  and 
such  charges  for  poor  condition  of  premises  or  faults  of  manage- 
ment as  are  warranted,  and  the  result  is  the  rate  for  insurance 
on  the  building  on  the  basis  of  the  insurance  carried  being  equal 
to  50  per  cent,  of  the  value.  If  the  amount  of  insurance  is 
greater  than  50  per  cent,  of  the  value  of  the  property  a  graded 
percentage  deduction  from  the  schedule  rate  is  permitted  for 
each  per  cent,  of  excess  over  50  per  cent.,  and  similarly,  if  the 
amount  of  insurance  is  less  than  50  per  cent,  of  the  value,  the 
schedule  rate  is  increased  by  a  graded  percentage,  the  policy 
contract  being  drawn  in  each  case  upon  a  specified  proportion 
of  insurance  to  value.  The  rate  for  contents  of  the  building  is 
obtained  by  adding  to  the  occupied  building  rate  a  charge  suffi- 
cient to  cover  the  additional  susceptibility  to  damage  by  fire, 
water  and  smoke  of  the  contents  over  the  building,  subject  to 
such  modifications  as  apply  to  contents  only.  This  suscepti- 
bility charge  has  already  been  established  for  each  of  the  thir- 
teen hundred  occupancies  already  referred  to. 

From  this  bare  outline  of  the  plan  of  the  'Universal 
Schedule'  it  will  be  seen  what  a  stupendous  work  has  been 
accomplished  by  its  author,  especially,  as  all  the  points  of  the 
schedule  were  submitted  to  hundreds  of  experts  for  criticism  be- 
fore being  adopted,  and,  therefore,  represent  the  consensus  of 
many  minds.  That  schedule  is  now  used  for  making  the  rates 


44  FIRE   PREVENTION   AND   FIRE   PROTECTION 

for  mercantile  buildings  in  New  York,  Boston  and  several  other 
cities,  haying  been  adapted  to  the  conditions  existing  in  each 
city,  and  is  the  basis  of  many  other  schedules  now  used;  in  fact, 
it  can  be  stated  without  fear  of  contradiction  that  no  rating 
schedule,  if  properly  made,  can  hereafter  escape  the  influence 
of  the  'Universal  Schedule.' 

There  is  also  a  schedule  for  rating  so-called  fireproof  build- 
ings by  the  same  author,  which  is  drawn  upon  the  same  general 
lines. 

Manufacturing  Schedules.  —  The  schedule  for  rating  manu- 
facturing buildings  goes  somewhat  further  into  detail  than  the 
mercantile  schedule,  but  its  arrangement  is  somewhat  simplified 
by  transposing  the  allowances  for  protective  features  from  de- 
ductions at  the  end  of  the  schedule  to  credits  at  the  beginning, 
which  can  in  that  way  be  applied  to  each  item  of  the  schedule 
charges  as  they  are  made,  thus  showing  at  a  glance  the  net 
charge  made  for  each  deficiency.  While  there  may  be  a  few 
classes  of  factories  that  could  not  properly  come  under  a  general 
schedule  of  this  kind,  because  owing  to  the  nature  of  the  work 
carried  on  they  require  buildings  especially  adapted  to  their 
particular  processes  of  manufacture,  a  very  large  majority  of 
factories  are  well  housed  in  such  a  building  as  has  been  adopted 
for  the  standard  of  this  schedule,  and  can,  therefore,  be  so  rated, 
provided  the  hazards  of  manufacturing  incidental  to  each  class 
of  factory  are  separately  treated.  By  this  plan  we  retain  the 
advantages  to  be  derived  from  having  but  one  standard  for 
the  construction  of  a  factory  building,  which  may  be  used  for 
almost  every  process  of  manufacture.  The  hazards  incidental 
to  different  processes  of  manufacture  are  clearly  features  of  the 
occupancy  of  the  building  and  should,  therefore,  be  treated  in 
connection  with  the  occupancy  charge  which  is  added  to  the 
rate  found  for  the  unoccupied  building,  which  rate,  as  explained 
in  the  case  of  the  mercantile  schedule,  is  composed  of  the  basis 
rate  for  the  standard  building  in  any  given  city  or  town,  and  the 
charges  for  deviations  from  standard  in  the  construction  of  the 
building.  In  establishing  the  occupancy  charge  for  any  par- 
ticular class  of  manufacture  it  is  necessary  to  first  adopt  stand- 
ards for  all  processes  entering  into  such  manufacture  and  to 
make  the  occupancy  charge  apply  only  to  a  plant  where  all  the 
processes  are  conducted  in  a  standard  manner,  and  any  devia- 
tions from  the  standards  adopted  for  each  process  must  then  be 
charged  for  separately  and  be  added  to  the  occupancy  charge. 
This  is  accomplished  by  the  adoption  of  a  schedule  of  charges  for 
such  defects,  which  virtually  becomes  a  separate  schedule  within 
the  schedule  for  determining  the  proper  occupancy  charge  for 
any  particular  factory.  These  occupancy  schedules,  so  to  speak, 
have,  for  want  of  a  better  name,  been  called  'coupons/  and  we 
have,  for  example,  a  boiler-house  coupon,  a  wood-worker  coupon, 
a  metal-worker  coupon,  etc.  When  the  proper  full  occupancy 
charge  has  thus  been  ascertained  by  means  of  the  coupon,  the 
schedule  can  be  applied  in  the  rating  of  a  manufacturing  building 


THEORY  AND   PRACTICE   OF   FIRE   INSURANCE        45 


in  the  same  manner  as  in  the  case  of  a  mercantile  building 
already  explained. 

Example  of  Rating:  An  example  of  rating  as  practiced 
by  the  Boston  Board  of  Fire  Underwriters  for  an  actual  Boston 
building  of  "  fireproof "  construction,  occupied  partly  by  offices 
and  partly  by  light  manufacturing  concerns,  is  as  follows: 

Rating  Slip.  —  Fireproof  Building. 

No...  ...Street. 


KEY  RATE 

Walls.  —  286,  if  skeleton  construction,  wrought-iron  or  steel  vertical 
supports  (no  charge  for  cast  iron),  charge  5  cents;  287,  average 
thickness  of  two-side  or  bearing  walls  (or  either  of  them),  less 
than  twenty  inches  (obtained  by  adding  thickness  of  various 
stories  and  dividing  by  the  number),  charge  for  each  inch  of  de- 
ficiency 2  cents;  if  any  portion  of  wall  less»than  twelve  inches, 
double  the  charge;  288,  if  front  or  side  walls  of  stone  or  veneered 
with  stone  ashlar,  plain  or  "  axed  "  finish,  charge  1  cent;  if  carved 
or  ornamental,  2  cents;  289,  bricks  or  mortar;  poor  quality,  20 
cents;  290,  columns  and  lower  flanges  of  beams  unprotected  (no 
charge  in  office  or  hotel  buildings),  5  cents. 

Wooden  Ceiling.  —  291,  Wood  or  strawboard,  etc.,  one  story,  1  cent; 
each  additional,  one-half  cent;  292,  side  walls,  wrood,  etc.,  one 
story,  1  cent;  each  additional,  one-half  cent. 

Area.  —  293,  5000  sq.  ft.  to  10,000,  each  1000  in  excess  of  5000,  J  of 
1  cent;  294,  if  over  10,000  sq.  ft.  each  1000  in  excess  of  10,000, 4  cents. 

(Not  exceeding  a  total  of  40  cents.) 

(If  building  occupied  exclusively  above  grade  floor  for  offices  or 
dwellings,  no  charge  for  area.) 

(NOTE.  —  If  mercantile  building  exceeds  ten  stories,  double 
area  charge.) 

Height.—  295,  For  each  story  over  eight  up  to  twelve,  charge  1  cent. 
(Office  buildings  may  be  ten  stories  without  charge.) 

296,  twelfth  story  and  each  story  over  twelve  up  to  fifteen,  3  cents. 

297,  fifteenth  and  each  story  over  fifteen,  charge  10  cents. 

If  merchandise  stored  above  seventh  floor,  charge  15  cents,  and 
add  2  cents  more  for  each  floor  over  seventh  up  to  tenth,  and  5 
cents  more  for  tenth  and  each  floor  above  tenth.  For  example, 
an  eleven-story  building  would  have  29  cents  added. 

Iron  Fronts.  —  298,  Not  backed  up  solidly  with  bricks  and  mortar, 
3  cents. 

Elevator.  —  299,  Not  cut  off  according  to  standard,  but  in  hallway 
or  enclosed  court,  etc.,  3  cents  (office  building,  charge  1  cent); 

300,  open,  6  cents  (office  building,  charge  3  cents); 

301,  enclosed  in  wood,  10  cents  (one-half  charge  for  office  building). 
(NOTE.  —  If  elevator  and  stairway  in  one  shaft  or  opening,  one 

charge  for  the  two.    For  each  additional  elevator  not  cut  add  2 
cents. ) 

Stairways.  —  302,  Not  cut  off  except  by  lath  and  plaster  hallway, 
etc.,  3  cents.  (No  charge  in  building  occupied  exclusively  above 
grade  for  offices  or  dwellings.) 

303,  if  enclosed  in  wood,  5  cents  (one-half  charge  in  office  bldg.). 

304,  open,  charge  1  cent  each  floor  not  exceeding  a  total  of  7  cents 
in  mercantile  building  and  2  cents  in  office  building;  305,  if  at  least 
one  stairway  is  not  fireproof  (no  charge  for  hard-wood  treads), 
charge  as  many  times  2  cents  as  the  building  has  floors. 


No. 


295 


304 


Charge 
26.0 
05. 


02. 


07. 


01. 
01. 


46 


FIRE   PREVENTION   AND    FIRE    PROTECTION 


(One-half  charge  for  302,  303,  or  304  if  charge  has  been  made  for 
299,  300  or  301.)  For  each  additional  stairway  add  one-fourth 
charge. 

Stairway  and  elevator  same  shaft  or  opening,  one  charge  for  the 
two. 

Well  holes,  etc,  —  306,  Open  for  each  floor  pierced,  1  cent.  (No 
charge  in  office  building.) 

Wooden  Chutes,  Ventilating  Shafts,  Dumb  Waiters  (unless  brick  shaft), 
Etc.  —  307,  each  floor  pierced,  one-fourth  cent. 

NOTE.  —  No  charge  need  be  made  for  openings  for  steam  and 
water  pipes  if  the  space  around  the  pipes  is  filled  in  with  mineral 
wool,  asbestos  or  other  incombustible  material,  or  otherwise  ar- 
ranged to  prevent  draughts  and  prevent  leakage  of  water  to  floor 
below. 

Skylights.  —  308,  Exceeding  nine  square  feet,  for  each  nine  square 
feet  (not  exceeding  total  of  10  cents),  1  cent;  309,  if  covered  with 
strong  wire  netting,  one-half  charge. 
(If  metallic  frames  and  heavy  deck,  or  prismatic  glass,  no  charge.) 

Street.  —  310,  If  street  on  which  building  fronts  is  less  than  sixty  feet 
wide,  but  over  fifty  (unless  opposite  side  vacant),  2  cents. 
311,  if  under  fifty  feet,  for  each  five  feet  under  fifty,  2  cents. 

Overhead  Wires,  Telegraph,  Etc,  —  312,  Sufficient  to  interfere  with 
working  of  fire  department,  according  to  quantity,  not  less  than 
one-half  cent. 

Number  of  Tenants.  —  313,  Each  in  excess  of  one,  exclusive  of  office 
and  dwelling  tenants,  1  cent. 

Lighting.  —  314,  If  by  electricity,  system  and  installation  in  com- 
pliance with  underwriters'  rules,  add  1  cent.  (If  not  in  compliance, 
see  No.  388,  page  63.) 


No. 


313 
314 


Charge 


25. 
01. 


320,  Result  rate  on  building  unoccupied 70 . 

Add  for  occupancy — (one-half  amount  in  first  column  of  table,  page  36).  7.5 

(Select  charge  for  most  hazardous  occupancy.) 

322,  Result  rate  on  building  occupied 77 . 5 

Deductions  for  Fire  Appliances,  Etc.,  on  Buildings.  ^         Per 

'     cent. 

340,  one  hydrant  supplied  by  8-inch  water  main,  within  300 

feet,  4% 340 } 

341 ,  two  or  more  hydrants  within  300  feet,  6% 341  [      10 

342,  if  said  water  pipe  be  fed  at  both  ends  by  mains,  4%  (10% 

in  all) 342  J 

344,  standpipe,  external  with  Siamese  connections,  for  use  of 
fire  department,  3% 

345,  standpipe,  internal,  with  tank  supply,  1% 345         01 

348,  if  building  occupied  exclusively  for  offices  or  dwellings, 
or  both,  20% 

349,  if  occupied  exclusively  for  offices  or  dwellings,  or  both, 
above  grade  floor,  10% 

350,  roof  hydrants,  1% 

351,  if  floors  waterproof  and  arranged  to  carry  off  water,  5% 

Total  deductions 11        8.5 

Exceptional  City  Fire  Department.  —  184,  extra  steamers,  \  of 
1%  for  each  one  in  excess  of  five  (not  exceeding  a  total  of 
20%);  185,  water  towers,  if  one,  2£%;  if  two,  5%;  186,  fire 

boat,  5% 184  \      23       69.0 

These  percentages  of  last  net  amount.     Total 185  f 

Result.  —  Net  rate  on  building  occupied,  unexposed 53  1* 


THEORY   AND   PRACTICE   OF   FIRE   INSURANCE        47 


Deductions  for  Fire  Appliances,  Etc.,  on  Stocks. 


357,  hydrants,  if  one,  supplied  by  8-inch  water  main  within 

300  ft.,  4% ' 357 

358,  two  or  more  supplied  by  8-inch  water  main  within  300  ft., 

6% 358  y     10 

359,  water  pipe  fed  at  both  ends  by  main,  additional  4%  (10% 

in  all) 359 

361,  if  merchandise  covered  by  tarpaulin  covers  each  night, 
5% 

362,  proximity  to  fire-department  station,  hose  or  hook  and 
ladder  house,  if  risk  within  300  feet,  2%;  if  next  door  or  on 
opposite  side  of  street,  5% 

365,  casks  of  water  or  filled  pails  (at  least  six  filled  pails  to 

each  2500  square  feet  of  floor  area),  3% 365         03 

366,  merchandise  in  tin-covered  cases,  5% 

367,  if  building  occupied  entirely  above  grade  floor  for  offices, 
5% ,. 

368,  if  building  occupied  entirely  for  offices  and  dwelling,  10% 

371,  standpjpe,  internal,  with  tank  supply,  1% 371         01 

372,  standpipe,  external  with  Siamese  connection,  for  the  use 
of  fire  department,  2% 

373,  if  one  or  more  chemical  engines  on  wheels,  5% 373         05 

375,  if  merchandise  on  skids  or  platforms  6  inches  high,  de- 
duct 2% 

376,  Grade-floor  Stocks.  —  Deduct  for  stock  entirely  on  grade 
floor,  3% 

If  stock  extends  over  only  one  additional  floor,  viz.,  sec- 
ond or  basement,  deduct  2% 

Total  deductions 19  t 

Exceptional  City  Fire  Department.  —  219,  Extra  Steamers, 
one  quarter  of  one  per  cent  (i  of  1%)  for  each  steamer  in  ex-      219  )      *.  ± 
cess  of  five  that  can  be  supplied  with  water  and  assembled      220  \ 
at  a  fire  (not  exceeding  15%  in  all);  220,  water  tower,  if  one, 
2J%,  if  two,  5%;  221,  fire  boat,  5%.    These  percentages  of 
last  net  amount 


No. 


Per 


48 


FIRE    PREVENTION    AND    FIRE    PROTECTION 


Floor. 

Building 

"  Name  of  light  ( 
manufacturing  I 
tenant."  ( 

O 

73 
g 

F 

15-65 

Occupancy 
charge. 

70.0 

Unoccupied 
building. 

65.0 

Stock. 

16.0 

Floor. 

Excess. 

j 

151.0 

Result. 

f!9%  t 

28.7 

i  Fire 
L    appliances. 

122.3 

Result. 

17.1 

14%  Excep- 
tion'l  F.  D.J 

53.1* 

105.2 

Result. 

26.6 

35.1 

80%  Ins. 

26.5 

70.1 

Result. 

15.5 

15.5 

Exposure. 

42.0 

85.6 

Result. 

Faults  of 
managem't 

Net. 

*  In  the  above  rating  of  occupants  one  light  manufacturing  tenantry  only 
is  given  as  an  example.  All  other  tenants  are  similarly  rated,  according  to 
their  hazard  of  occupancy,  but  the  final  rate  is  governed  by  the  hazard  of  the 
most  dangerous  occupant. 


THEORY   AND    PRACTICE    OF   FIRE    INSURANCE        49 

Rating  Organizations.  —  In  former  years,  each  fire  insur- 
ance company  determined  its  own  rates,  but,  with  the  growth 
of  business,  liability  and  competition,  the  need  of  broader  data 
and  collective  experience  led  to  the  organization  of  the  "  local 
board  "  by  the  insurance  companies  of  a  city  or  locality.  The 
original  purpose  of  the  local  board  was  simply  to  make  rates 
for  its  constituent  companies,  but  again,  under  a  process  of 
gradual  development,  the  local  board  (variously  called  Board 
of  Fire  Underwriters,  or  Fire  Underwriters'  Association,  etc.) 
not  only  determines  rates  at  the  present  time  for  its  component 
companies,  but  acts,  as  well,  as  a  bureau  of  information  where 
owners,  architects  and  builders  may  obtain  specific  data  regard- 
ing the  effects  on  rates  of  all  matters  pertaining  to  the  con- 
struction, occupancy  and  protection  of  buildings,  or  to  contents. 
Such  information  is  furnished  for  existing  structures,  or  for 
prospective  buildings,  to  the  end  that  each  owner  or  tenant  may 
secure  the  lowest  possible  rating,  provided  he  fulfils  the  require- 
ments of  the  board. 

In  addition  to  inspections  of  property  to  determine  new  ratings, 
the  local  board,  through  its  inspection  department,  makes  more 
or  less  frequent  inspections  of  all  property  within  its  jurisdiction 
for  the  purpose  of  noting  " defects"  or  changes  of  occupancy 
which  have  any  bearing  on  the  hazards. 

As  an  example  of  the  functions  of  a  local  board  of  under- 
writers, the  following  quotation  from  the  constitution  of  the 
Philadelphia  Fire  Underwriters'  Association  is  of  interest: 

The  object  of  this  association  shall  be  the  reduction  of  the 
fire  waste  in  the  City  of  Philadelphia,  the  establishment  of 
just  and  fair  rates,  limited  and  perpetual,  whereby  the  cost  of 
fire  insurance  may  be  equitably  distributed  among  all  classes 
of  manufacturers,  merchants,  private  householders  and  others. 
For  this  purpose  the  association  will  establish  a  system  of 
schedule  and  minimum  ratings,  giving  the  best  risks  the  lowest 
rates,  and  adding  specific  charges  for  all  deficiencies  from  re- 
quired standards,  making  reductions  from  such  rates  when  defi- 
ciencies charged  for  are  eliminated,  and  also  providing  rules  for 
regulating  the  practices  of  the  business  of  fire  underwriting  in 
the  City  of  Philadelphia. 

Each  local  board  is  under  the  direct  control  of  its  constituent 
companies,  through  an  executive  committee. '  The  organization 
of  a  board  usually  comprises  a  secretary,  a  superintendent  of 
ratings,  and  a  superintendent  of  inspection. 


50  FIRE    PREVENTION    AND   FIRE   PROTECTION 

The  National  Board  of  Fire  Underwriters.  —  The  lack  in 
the  United  States  of  such  governmental  supervision  as  is  given 
by  England  and  several  continental  nations  to  questions  of  fire 
prevention  and  fire  protection,  has  naturally  led,  through  the 
law  of  self-preservation,  to  the  combination  or  cooperation  of 
insurance  companies.  This  has  been  effected,  as  far  as  rating 
etc.  is  concerned,  through  the  local  board,  as  previously  de- 
scribed, and,  also,  in  a  broader  way,  through  the  National 
Board  of  Fire  Underwriters.  This  association,  which  now  in- 
cludes one  hundred  and  twenty-four  insurance  companies  in  its 
membership,  declares  its  objects  and  purposes  to  be  as  follows: 

1st.  To  promote  harmony,  correct  practices  and  the  prin- 
ciples of  sound  underwriting.  To  devise  and  give  effect  to 
measures  for  the  protection  of  the  common  interests,  and  the 
promotion  of  such  laws  and  regulations  as  will  secure  stability 
and  solidity  to  capital  employed  in  the  business  of  fire  insur- 
ance, and  protect  it  against  oppressive,  unjust  and  discrimina- 
tive legislation. 

2d.  To  repress  incendiarism  and  arson  by  combining  in 
suitable  measures  for  the  apprehension,  conviction  and  punish- 
ment of  criminals  guilty  of  that  crime. 

3d.  To  gather  such  statistics  and  establish  such  classifica- 
tion of  hazards  as  may  be  for  the  interest  of  members. 

4th.  To  secure  the  adoption  of  uniform  and  correct  policy 
forms  and  clauses  and  to  endeavor  to  agree  upon  such  rules  and 
regulations  in  reference  to  the  adjustment  of  losses  as  may  be 
desirable  and  in  the  interest  of  all  concerned. 

5th.  To  influence  the  introduction  of  improved  and  safe 
methods  of  building  construction,  encourage  the  adoption  of  fire 
protective  measures,  secure  efficient  organization  and  equipment 
of  fire  departments  with  adequate  and  improved  water  systems, 
and  establish  rules  designed  to  regulate  all  hazards  constituting 
a  menace  to  the  business.  Every  member  shall  be  in  honor 
bound  to  cooperate  with  every  other  member  to  accomplish  Mi<> 
desired  objects  and  purposes  of  the  Board. 

The  carrying  out  of  the  above  purposes  is  principally  effected 
through  standing  committees  and  their  work  as  follows:* 

A  committee  on  finance. 

A  rnn^flfek  on  laws,  which  takes  charge  of  all  legal  and  legis- 
lative mat^ra  which  concern  the  interests  of  all  companies. 

A  committee  on  incendiarism  and  arson,  which  authorizes 

offers  of  reward  for  the  detection  and  conviction  of  incendiaries. 

• 

*  For  a  more  detailed  account,  see  "The  National  Board  of  Fire  Under- 
writers, Its  early  History,  together  with  a  Statement  of  its  Present  Work," 
by  George  W.  Babb,  Vice-President. 


THEORY   AND    PRACTICE    OF   FIRE    INSURANCE        51 

The  Arson  Fund  has  been  in  existence  for  over  thirty  years, 
and  of  6000  rewards  offered,  490  convictions  have  been  secured. 

A  committee  on  statistics  and  origin  of  fires,  which,  for  many 
years,  has  compiled  and  published  statistics  of  fires  in  American 
cities  of  a  population  of  20,000  and  upwards.  In  1905  this 
committee  induced  the  United  States  Government  to  require 
its  consuls  abroad  to  obtain  statistics  of  fires  in  the  cities  and 
countries  to  which  they  were  accredited,  with  the  result  that  a 
special  consular  report,  "  Insurance  in  Foreign  Countries,"  was 
published  in  1905. 

A  committee  on  fire  prevention,  which  has  been  engaged  in 
the  work  of  investigating  conditions  pertaining  to  the  water 
supply,  fire  departments,  and  structural  conditions  of  cities. 

From  1890  to  1904  the  committee  on  water  supply  and  fire 
department  had  this  work  in  charge  with  only  one  inspector  in 
the  field,  and  during  that  time  747  cities  or  towns  in  38  different 
states  were  visited  and  reports  issued  thereon. 

After  the  Baltimore  fire  in  1904  the  Committee  of  Twenty 
was  appointed  and  the  force  to  carry  on  the  work  largely  in- 
creased, about  forty  (office  and  field)  men  being  employed. 
The  work  continued  on  this  scale  for  two  years,  during  which 
time  48  cities,  many  of  the  number  being  the  larger  ones,  were 
inspected. 

In  1906  these  two  committees  were  merged  into  one,  under 
the  title  of  the  Committee  on  Fire  Prevention,  with  a  force  of 
about  20  (office  and  field)  men,  and  during  the  two  years  ending 
in  May  last  75  cities  were  inspected  upon  which  reports  were 
issued. 

Since  the  inauguration  of  the  work,  over  900  cities  and  towns 
have  been  inspected  and  reported  upon. 

A  committee  on  lighting,  heating  and  patents,  having  in  charge 
devices  for  lighting  and  heating  and  the  proper  rules  for  enforce- 
ment regarding  same. 

A  committee  on  construction  of  buildings,  which,  with'  the 
aid  of  architects,  has  prepared  the  building  code  mentioned  in 
Chapter  II,  page  32.  The  appointment  (1910)  of  Professor 
Ira  H.  Woolson  as  an  expert  to  carry  on  the  work  of  this  com- 
mittee insures  an  active  prosecution  of  the  betterment  of  mu- 
nicipal building  codes  throughout  the  country. 

A  committee  on  adjustment,  to  secure  uniformity  of  action 
in  withholding  hasty  payments  of  losses  before  payments  become 
due. 

A  committee  on  clauses  and  forms. 


52  FIRE    PREVENTION    AND    FIRE    PROTECTION 

In  addition  to  the  above-mentioned  standing  committees, 
there  has  been  a  special  committee  of  consulting  engineers  in 
charge  of  all  lighting  and  heating  hazards  other  than  electricity. 
The  tests  and  reports  upon  these  subjects,  made  by  the  Under- 
writers' Laboratories,  Incorporated,  are  passed  upon  by  this 
committee,  which  then  prepares  and  issues  standard  specifica- 
tions regarding  such  hazards.  These  standards  are  widely 
accepted  as  authoritative,  even  outside  of  insurance  circles. 
The  range  of  subjects  includes  Acetylene,  Calcium  Carbide, 
Coal  Gas  Producers,  Fuel  Oil,  Gas  and  Gasolene  Engines,  Gaso- 
lene Lighting  and  Stoves,  Grain  Dryers,  Storage  of  Inflammable 
Fluids,  Kerosene  Oil  Pressure  Systems,  and  Moving  Picture 
Films.  Up  to  1910,  this  committee  had  passed  upon  over 
1100  laboratory  reports  on  such  subjects.  This  committee  of 
consulting  engineers  has  lately  been  merged  into  the  National 
Fire  Protection  Association. 

The  Underwriters'  Laboratories,  Incorporated,  (described  in 
Chapter  V,  page  119)  is  principally  supported  by  and  under  the 
direction  of  the  National  Board,  which  is,  therefore,  the  chief 
central  organization  of  fire  insurance  interests  in  the  United 
States.  The  National  Board  promulgates  to  its  members  those 
standard  rules  and  regulations  formulated  by  its  committee  of 
consulting  engineers,  or  recommended  by  the  National  Fire 
Protection  Association,  and  also  lists  of  manufacturers  making 
materials  or  devices  which  are  approved  by  the  Underwriters' 
Laboratories. 

The  Underwriters'  National  Electric  Association  was 
formed  several  years  ago  at  the  suggestion  of  the  National  Board. 
This  association  is  composed  of  the  electrical  experts  in  the  em- 
ploy of  the  several  Underwriting  Associations  and  Inspection 
Bureaus  throughout  the  country,  who  formulate  uniform  rules 
designed  to  minimize  the  hazard  of  electricity.  The  electrical 
committee  of  that  association  reports  its  recommendations  from 
time  to  time  to  the  National  Board,  which,  after  approval, 
promulgates  the  same  under  the  designation  "National  Electrical 
Code."  This  code  is  almost  invariably  accepted  as  standard. 
Since  early  in  1911,  this  association,  also,  has  been  merged  into 
the  National  Fire  Protection  Association. 

The  National  Fire  Protection  Association  was  formed 
November  6,  1896,  as  a  result  of  the  wide  divergence  of  ideas 
and  non-uniformity  of  practice  then  existing  on  the  part  of 


THEORY   AND   PRACTICE   OF   FIRE   INSURANCE        53 

underwriters,  inspection  bureaus,  and  other  insurance  organi- 
zations throughout  the  United  States.  The  object  of  this 
association  is  "to  bring  together  the  experience  of  different 
sections  and  different  bodies  of  underwriters,  to  come  to  a  mutual 
understanding,  and,  if  possible,  an  agreement  on  general  prin- 
ciples governing  fire  protection;  to  harmonize  and  adjust  differ- 
ences, so  that  we  may  go  before  the  public  with  uniform  rules 
and  conditions  which  may  appeal  to  their  judgment."*  The 
association  does  not  consider  the  subjects  of  insurance  rates  or 
compensation  to  agents. 

While  the  primary  object  of  this  association  was  to  harmonize 
or  standardize  various  insurance  practices,  its  continued  growth 
and  influence  has  gradually  led  to  broader  endeavors,  especially 
along  the  line  of  encouraging  all  matters  pertaining  to  fire  pre- 
vention and  fire  protection.  The  publicity  campaign  inaugu- 
rated by  this  association  has  been  previously  mentioned. 

The  following  extract  from  the  " articles  of  association"  define 
the  objects  and  membership  of  the  organization: 

ARTICLE  1 .  —  This  organization  shall  be  known  as  the  Na- 
tional Fire  Protection  Association. 

ARTICLE  2.  —  The  objects  of  this  association  shall  be  to 
promote  the  science  and  improve  the  methods  of  fire  protection 
and  prevention;  to  obtain  and  circulate  information  on  these 
subjects  and  to  secure  the  cooperation  of  its  members  in  estab- 
lishing proper  safeguards  against  loss  of  life  and  property  by 
fire. 

ARTICLE  3.  —  Membership  shall  consist  of  (a)  Active,  (6) 
Associate,  (c)  Subscribing,  and  (d)  Honorary.  It  is  understood 
that  through  membership  none  is  pledged  to  any  course  of 
action. 

(a)  Active  Members.  —  National  Institutes,   Societies   and 
Associations  interested  in  the  protection  of  life  and  property 
against  loss  by  fire;  -  State  Associations  whose  principal  object 
is  the  reduction  of  fire  waste;    Insurance  Boards  and  Insurance 
Associations  having  primary  jurisdiction  shall  be   eligible  for 
active  membership.     Annual  dues  shall  be  $15. 

(b)  Associate   Members.  —  National,    State   and   Municipal 
Departments  and  Bureaus,  Boards  of  Trade,  Chambers  of  Com- 
merce and  similar  business  men's  associations;  Insurance  Boards 
and  Insurance  Associations  not  eligible  for  active  membership; 
Individual   members   of   the   organizations   represented   in   the 
active  or  associate  membership;  Individuals  engaged  in  the  fire 
insurance  business  shall  be  eligible  for  associate  membership. 
Annual  dues  shall  be  $5. 

*  Mr.  U.  C.  Crosby,  report  of  executive  committee,  at  First  Annual  Meeting. 


54  FIRE   PREVENTION   AND   FIRE   PROTECTION 

(c)  Subscribing  Members.  —  Individuals,  firms  and  corpo- 
rations interested  in  the  protection  of  life  and  property  against 
loss  by  fire  shall  be  eligible  for  subscribing  membership.  Annual 
dues  shall  be  $5. 

The  active  membership  now  includes  over  ninety  of  the  prin- 
cipal National  Institutes,  Societies,  Associations,  and  Insurance 
Boards  of  the  United  States.  Special  committees  investigate 
a  wide  range  of  subjects  pertaining  to  fire  prevention  and  fire 
protection,  and  after  the  reports  of  these  committees  are  ac- 
cepted at  the  annual  meetings  of  the  association,  they  are  also 
accepted  by  the  National  Board  and  published  and  distributed 
as  National  Board  Standards. 

The  National  Board  officials  have  long  felt  the  desirability  of 
unifying  the  sources  from  which  that  body  has  for  so  many  years 
drawn  its  various  codes  and  standards.  The  National  Fire 
Protection  Association  has  furnished  standards  for  all  protective 
devices  and  systems;  the  Consulting  Engineers  have  handled 
the  hazards  of  gases  and  oils,  and  the  Underwriters'  National 
Electric  Association  has  been  responsible  for  the  National 
Electrical  Code.  These  three  standard-making  bodies  have 
now  been  merged  into  one,  —  the  National  Fire  Protection  Asso- 
ciation —  and  the  work  of  the  two  other  bodies,  which  have 
ceased  to  exist  as  detached  organizations,  is  conducted  by 
special  committees  of  the  National  Fire  "Protection  Association. 
The  Underwriters'  National  Electric  Association  is  now  entitled 
the  Electrical  Committee,  and  the  Consulting  Engineers  are 
called  the  Committee  on  Explosives  and  Combustibles  of  the 
National  Fire  Protection  Association.  The  personnel  of  the 
new  committees  is  identical  with  that  of  the  two  former  separate 
bodies,  with  the  addition  to  each  of  one  or  two  desirable  members. 
Thus  the  National  Board  has  not  lost  the  benefit  of  the  counsel 
of  the  men  who  so  long  rendered  exceptionally  valuable  service 
in  the  two  bodies,  and  the  National  Fire  Protection  Association 
has  gained  in  influence  and  dignity  by  this  striking  addition  to 
its  responsibilities  and  such  manifestation  of  confidence  on  the 
part  of  the  National  Board. 

Specifications,  Rules  and  Requirements,  published  by 
the  National  Board  of  Fire  Underwriters,  upon  recommendation 
of  the  National  Fire  Protection  Association  are  as  follows: 


THEORY  AND   PRACTICE   OF   FIRE   INSURANCE        55 


SUBJECTS. 

Acetylene  Gas  Machines  and  Storage  of  Calcium  Carbide. 

Coal  Gas  Producers  (pressure  and  suction  systems). 

Electric  Wiring  and  Apparatus,  Installation  Rules  (National 
Electrical  Code). 

Electrical  Fittings,  List  of  Approved. 

Fire  Departments,  Private. 

Fire  Doors  and  Shutters. 

Fire  Extinguishers,  Chemical  (for  other  than  fire  depart- 
ment use). 

Fire  Hose  for  fire  department  use. 

Fire  Hose,  for  private  department  mill-yard  use. 

Fire  Hose,  Unlined  Linen,  for  use  inside  buildings. 

Fire  Pumps  (steam). 

Fire  Pumps  (electric). 

Fire  Pumps  (centrifugal). 

Fire  Pumps  (rotary). 

Gas  and  Gasolene  Engines. 

Gasolene  Vapor  Gas  Lighting  Machines,  Lamps  and  Sys- 
tems. 

Gasolene  Vapor  Stoves,  for  cooking  and  heating. 

Grain  Dryers. 

Gravity  Tanks. 

Hose  Couplings  and  Hydrant  Fittings,  for  public  fire  service. 

Hose  Houses,  for  mill  yards. 

Incubators  and  Brooders. 

Kerosene  Oil  Pressure  Systems. 

Lightning,  Protection  Against. 

Nitrocellulose  Films  (storage  and  handling). 

Oil  Storage  (fuel),  storage  and  use  of  fuel  oil  and  construc- 
tion and  installation  of  oil-burning  equipment. 

Oil  Storage  (inflammable),  systems  for  storing  250  gallons 
or  less  of  fluids  which  at  ordinary  temperatures  give  off 
inflammable  vapors. 

Oxyacetylene  Heating  and  Welding  Apparatus. 

Railway  Car  Houses  (storage  and  operating),  Construction 
and  Protection  of. 

Signaling  Systems,  used  for  the  transmission  jrf  signals 
affecting  the  fire  hazard. 

Skylights. 

Sprinkler  Equipments,  automatic  and  open  systems. 

Steam  Pump  Governors  and  Auxiliary  Pumps. 

Uniform  Requirements  (" slow-burning"  construction,  " in- 
ferior'7 construction,  general  hazards,  oil  rooms,  general 
protection,  stairway  and  elevator  closures,  watchmen, 
thermostats,  etc.). 

Valves,  Indicator  Posts  and  Hydrants  for  mill-yard  use. 

Wraste  Cans,  Ash  Cans,  Refuse  Barrels,  Fire  Pails  and 
Safety  Cans  for  Benzine  and  Gasolene. 

Wired  Glass  and  Metal  Window  Frame  Construction. 


56  FIRE   PREVENTION   AND   FIRE   PROTECTION 

Underwriters'  Laboratories,  general  information  in  reference 
to  the  nature  of  its  work  and  the  terms  and  conditions 
under  which  tests  of  fire  appliances  and  materials  are 
conducted. 

Any  or  all  of  the  above  standards  may  be  obtained  gratis  by 
addressing  the  National  Board  of  Fire  Ujadels^riters,  135  William 
St.,  New  York.  X  \ 

Inspection  Bureaus  are  formed  an^ssupported  by  the  in- 
surance companies  doing  business  withm  a  stated  territory. 
They  perform  for  such  companies  a  systematized  and  centralized 
service  of  inspection,  exactly  as  do  the  local  boards  in  the  matter 
of  rating.  Thus,  if  no  local  board  existed,  each  company  would 
have  to  determine  its  own  rating,  as  has  been  shown.  Similarly, 
if  no  inspection  bureaus  existed,  the  individual  companies  would 
each  have  to  maintain  competent  inspectors,  as  demanded  by 
conservative  underwriting,  to  follow  up  the  hazards  or  defects 
of  risks  underwritten  by  their  agents  or  general  agent. 

If  a  large  plant,  for  example,  were  insured  in  ten  insurance 
companies,  this  would  mean  not  only  the  maintenance  of  an 
inspection  force  by  each  of  the  ten  companies  to  inspect  from 
time  to  time  the  condition  of  the  risk,  but,  also,  that  the  owners 
of  such  a  plant  would  be  put  to  the  trouble  of  allowing  ten  visits 
of  inspection  from  these  representatives,  each  of  whom,  owing 
to  the  personal  equation  involved,  would  submit  a  more  or  less 
different  report  to  his  company  as  to  defects  to  be  remedied,  etc. 
The  owners  would  then  probably  receive,  at  intervals,  ten  differ- 
ent letters  of  complaint  from  the  companies,  asking  for  various 
corrections  of  defects. 

A  centralized  inspection  bureau,  representing  all  of  the  ten 
companies,  therefore  acts  in  an  authoritative  inspection  capacity, 
making  inspections  at  stated  intervals,  usually  twice  a  year. 
The  results  of  these  inspections  are  then  promulgated  to  all  of 
the  supporting  companies  interested  in  the  risk. 

Mutual  Fire  Insurance  Companies.  —  Reference  is  made 
elsewhere  to  the  wonderful  record  of  manufacturers'  Mutual 
Companies  in  reducing  both  losses  and  rates  (see  Chapters  IV 
and  XXX).  Such  companies  were  the  pioneers  in  the  matters 
of  protection  or  auxiliary  equipment,  especially  as  regards  the 
development  and  improvement  of  automatic  sprinklers,  and  their 
success  in  this  direction  did  much  to  force  the  stock  fire  insur- 
ance companies  to  proceed  along  similar  lines  of  protection. 


THEORY   AND   PRACTICE   OF   FIRE   INSURANCE        57 

The  mutual  companies  were  originally  organized  on  the  assess- 
ment plan,  but,  while  liability  to  the  insured  through  assessment 
is  still  possible  in  case  of  great  losses,  the  usual  yearly  losses  are 
covered  by  annual  premiums,  on  which  dividends  are  paid 
back  to  the  insured  at  the  end  of  the  policy  year.  Such  divi- 
dends are  based  on  the  annual  premium  receipts,  less  losses  and 
expenses,  and  80  to  90  per  cent,  dividends  are  not  uncommon. 
Insurance  is  a  Tax. — While  fire  insurance  is  undoubtedly 
an  institution  of  great  benefit,  in  that  fire  losses  are  distributed 
over  an  entire  community  or  over  the  country  at  large,  instead 
of  upon  individuals,  nevertheless  the  consequent  pro-rata  tax 
upon  the  individual  still  remains. 

It  is  a  singular  commentary  upon  American  acuteness 
that  the  citizens  of  the  United  States  do  not  yet  discern  that  fire 
insurance  is  a  tax,  shifted  through  the  buying  and  selling  pro- 
cesses upon  the  entire  community;  that  every  fire  hazard  tends 
to  increase  this  tax,  and  that  every  element  of  fire  prevention 
tends  to  lessen  it.  Merchants  and  manufacturers  must  pass 
along  the  cost  of  insuring  their  goods  to  the  people  who  consume 
those  goods,  however  this  tax  is  concealed  in  the  selling  price, 
and  the  amount  of  rent  which  every  man  pays  for  office  or  tene- 
ment is  affected  by  the  cost  of  insuring  the  building  occupied. 

The  unintelligent  legal  attacks  sometimes  made  by  com- 
munities upon  rating  organizations  are  based  upon  the  notion 
that  the  money  paid  by  insurance  companies  in  settlement  of 
fire  losses  comes  from  some  remote  source,  from  some  inexhausti- 
ble treasure-house  which  has  never  to  be  refilled.  And  yet  it 
should  be  obvious  that  insurance  companies  could  not  continue 
in  business  if  losses  were  paid  out  of  their  capital;  if  they  did 
not  assess  the  losses  paid  to  the  unfortunate  individual  upon  a 
large  number  of  more  fortunate  individuals,  and  through  the 
latter  upon  the  whole  commonwealth.  In  great  conflagrations 
insurance  companies  have  indeed  paid  their  losses  with  their 
capital,  sometimes, to  its  utter  extinction,  or  even  to  an  assess- 
ment upon  their  stockholders  to  meet  honorably  their  obliga- 
tions; but  such  abnormal  conditions,  if  long  continued,  would 
make  the  business  of  underwriting  impossible.  Insurance  capi- 
tal is  merely  a  reservoir  from  which  flows  immediate  relief  for 
the  victim  of  fire,  who,  because  of  this  reservoir,  need  not  wait 
to  recoup  his  misfortune;  but  this  reservoir  must  be  refilled,  and 
kept  full,  if  sure  relief  is  to  flow  to  succeeding  sufferers.* 

But  this  very  fact,  that  the  insurance  tax  is  distributed  over 
the  many  instead  of  directly  upon  the  sufferer  of  the  loss,  often 

*  Franklin  H.  Wentworth,  Secretary  National  Fire  Protection  Association, 
in  address  before  Ninth  Annual  Meeting  of  Texas  Fire  Prevention  Association, 
1909. 


58 


FIRE    PREVENTION    AND    FIRE    PROTECTION 


proves  one  great  objection  to  the  institution  of  fire  insurance. 
For  if  each  individual  property  owner  could  be  made  to  feel 
directly  the  total  loss  resulting  from  defects  in  his  property,  as 
is  true  in  some  European  countries  (see  Chapter  I,  page  16), 
the  questions  of  fire  loss  and  fire  protection  would  soon  be 
regulated. 

Some  Insurance  Statistics.  —  In  Chapter  I,  many  statistics 
were  given  concerning  fire  losses  in  the  United  States.  These 
were  considered  only  from  the  standpoint  of  the  loss  or  waste 
involved.  Some  of  these  figures  will  now  be  analyzed  somewhat 
from  the  insurance  view-point. 

The  following  table*  shows  the  risks  written,  premiums  and 
losses,  and  ratio  of  losses,  for  United  States  Insurance  Com- 
panies, from  1860  to  1909. 


Year. 

No.  of 
com- 
panies. 

Fire  risks 
written. 

Fire  premi- 
ums re- 
ceived. 

Fire  losses 
paid. 

Ratio 
losses 
to  $100 
of  pre- 

Ratio 
losses 
to  $100 

risks. 

Am't 
risks 
writ- 
ten to 
$1.00 

miums. 

loss. 

Inch 

1860-70 

Av. 

142 

34,498,550,693 

275,713,179 

160,518,049 

58.22 

.4653 

214.92 

1871-80 

162 

48,984,381,358 

426,857,520 

247,406,065 

57.96 

.5051 

197.99 

1881-90 

128 

66,440,863,967 

566,266,362 

325,484,632 

57.48 

.4899 

204.13 

1891-00 

112 

99,853,242,504 

814,475,128 

481,210,797 

59.08 

.4819 

207.50 

1901 

110 

13,605,011,561 

107,754,361 

61,125,610 

56.73 

.4493 

222.57 

1902 

112 

14,571,479,297 

126,162,843 

65,647,571 

52.03 

.4505 

221.96 

1903 

114 

15,304,969,722 

135,524,226 

64,665,648 

47.71 

.4225 

236.67 

1904 

112 

16,472,319,419 

146,562,454 

88,355,032 

60.29 

.5277 

189.49 

1905 

126 

18,112,291,243 

158,426,265 

74,238,556 

46.86 

.4098 

243.97 

1906 

126 

19,291,315,915 

168,221,731 

142,125,040 

84.49 

.7368 

135.73 

1907 

138 

21,739,515,448 

186,019,961 

84,289,339 

45.31 

.3877 

257.91 

1908 

131 

21,589,707,144 

180,779,931 

98,955,807 

54.74 

.4583 

218.18 

1909 

132 

23,613,622,056 

192,312,129 

92,604,484 

48  15 

.3922 

255.00 

1860-1909 

414,347,270,327 

3,484,876,290 

1,986,626,630 

57.01 

.4794 

208.57 

During  the  same  period,  viz.,  1860-1909  inclusive,  the  ratio 
of  the  expenses  of  United  States  Insurance  Companies  to  $100 
of  premiums  received,  was  36.72,  which,  added  to  the  ratio  of 
fire  losses  paid  to  $100  of  premiums  (or  57.01  as  per  previous 
table),  makes  a  total  ratio  of  loss  and  expense  to  $100  of  premi- 
ums of  93.73  for  the  forty-nine-year  period.  The  average  profit 
of  underwriting  for  that  period  was,  therefore,  6.27  per  cent. 


*  See  "Proceedings  of  forty-fourth   Annual  Meeting   (1910)    of  National 
Board  of  Fire  Underwriters." 


THEORY   AND   PRACTICE   OF   FIRE   INSURANCE 


59 


But,  owing  to  the  almost  steady  increase  in  the  expense  ratio 
from  year  to  year,  and  the  increase  in  both  general  fire  losses 
and  in  conflagrations  during  late  years  (as  has  been  pointed  out 
in  Chapter  I),  the  showing  from  the  insurance  standpoint  over 
a  period  of  say  the  ten  years  from  1900  to  1909  inclusive  is  much 
worse  than  is  indicated  by  the  above  ratio  for  49  years.  Thus, 
while  the  underwriting  result  for  1909  shows  a  profit  for  the  year 
of  GiVo  per  cent.,  as  follows: 


$131,184,351 


18,520,586 
104,628,486 

17,426,938 


Premiums,  fire,  marine  and 

inland : . .  $271,760,361 

Losses  paid,  fire,  marine  and 
inland 

Increase  in  liabilities  during  the 
year  (outstanding  losses, 
unearned  premiums  and  all 
other  claims) 

Expenses 

Profit  (6rVo  per  cent,  of  pre- 
miums)   


$271,760,361        $271,760,361 

the  ten-year  table  shows  a  loss  of  2T-§-^  per  cent,  for  the  period 
1900  to  1909,  inclusive,  as  follows: 

Premiums,     fire,     marine    and 

inland $2,159,695,029 

Losses  paid,    fire,   marine    and 

inland $1,251,628,708 

Increase  in  liabilities  during  the 

period  (outstanding  losses, 

unearned  premiums  and  all 

other  claims) 136,729,669 

Expenses 816,348,441 

Loss  (2T|o  per  cent.) 45,011,789 


$2,204,706,818     $2,204,706,818 

This  is  principally  attributable  to  the  frequent  recurrence 
and  to  the  increasing  losses  of  conflagrations.  The  year  1909, 
which  showed  an  underwriting  profit  as  above,  included  no  con- 
flagration exceeding  $1,000,000  in  loss,  while  the  ten-year  period 


60          FIRE   PREVENTION   AND   FIRE    PROTECTION 

included  great  losses  at  Jacksonville  in  1901,  at  Baltimore  in 
1904,  at  Chelsea  in  1908  and  at  San  Francisco  in  1906.  In 
the  latter  disaster  alone,  the  insurance  companies  paid  over 
$70,000,000  of  fire  losses,  or  an  amount  almost  equivalent  to 
the  present  capital  stock  of  all  fire  insurance  companies  doing 
business  in  this  country. 

As  a  result  of  these  or  similar  conditions,  one  thousand 
fire  insurance  companies,  or  more  than  three  times  the  present 
number  of  companies,  have  failed  or  retired  since  1860,  .  .  . 
and  it  is  a  significant  fact  that  some  of  the  European  companies 
writing  policies  in  this  country  are  seriously  considering  with- 
drawal. 

A  fire  in  the  congested  value  district  of  New  York  City, 
covering  an  area  as  large  as  that  of  the  San  Francisco  conflagra- 
tion, would  put  out  of  existence  nearly  every  fire  insurance 
company  doing  business  in  this  country. 

The  arrant  individualism  of  the  American  character  as- 
sumes that  the  underwriting  interests  can  look  out  for  them- 
selves, and  raise  premium  rates  to  cover  their  losses,  absolving 
the  public  from  all  responsibility  save  the  payment  of  the  in- 
creased tax;  but  there  is  a  limit  beyond  which  honest  com- 
panies will  not  go  in  such  a  gamble,  and  that  limit  must  mean 
the  disappearance  of  reliable  insurance,  and  the  consequent 
instability  of  credits.  Reputable  companies  are  already  steadily 
narrowing  the  limits  of  their  risks,  while  the  constantly  increas- 
ing hazard  and  loss  operates  to  discourage  capital  from  the 
business  of  underwriting.* 

On  January  1,  1906,  United  States  fire  insurance  companies 
showed  a  -ratio  of  loss-paying  power  to  amount  at  risk  of  66  cents 
per  $100.  On  January  1,  1910,  this  same  ratio  had  decreased 
to  58  cents  per  $100,  thus  showing  that  the  strength  of  the  com- 
panies, taken  as  a  whole,  is  considerably  less  than  it  was  before 
the  year  of  the  San  Francisco  conflagration. 

Conflagration  Liability.  —  The  serious  consideration  by 
underwriters  of  the  facts  enumerated  in  the  previous  paragraph, 
has  led  to  the  suggestion  that  the  fire  insurance  companies  of 
the  United  States  agree,  as  a  requisite  of  self-preservation,  upon 
some  limitation  of  liability  in  the  event  of  conflagration. 

It  is  a  conceded  proposition  among  all  men  that  unless 
the  interest  of  the  insured  or  the  property  owner  can  be  enlisted, 
efforts  for  the  prevention  of  fire  loss  will  be  largely  fruitless. 
This  being  so,  let  us  ask  if  any  method  has  been  proposed  which 
would  so  bring  the  question  home  to  the  property  owner  and  to 

*  1909  "Proceedings  of  National  Fire  Protection  Association,"  page  39. 


THEORY   AND   PRACTICE    OF   FIRE    INSURANCE        61 

our  municipal,  state  and  national  governments,  or  that  would 
so  enlist  their  cooperation  in  the  prevention  of  fire,  as  the 
simple  proposition  that  the  underwriting  interests  would  not 
carry  the  conflagration  hazard.  But  how  ure  we  going  to  do  this? 
Simply  by  writing  our  policies  on  a  limited  liability  plan.  It 
would  not  be  difficult  to  ascertain  the  amount  of  insurance 
carried  in  any  city  or  iii  the  individual  blocks  of  that  city,  and 
the  policies  would  be  issued  good  for  a  certain  amount  if  the  fire 
was  confined  to  the  insured's  own  premises  or  the  building 
which  he  occupied,  for  less  if  it  spread,  or  the  entire  block 
might  be  taken  for  the  next  factor,  with  a  minimum  amount  if 
a  conflagration  occurred  in  the  city.  Possibly  the  suggestion 
is  radical  but  perhaps  somewhat  radical  suggestions  are  needed 
at  this  time.  .  .  . 

In  conclusion,  we  are  not  unmindful  of  the  fact  that  vari- 
ous remedies  have  been  proposed,  such  as  schedule  rating,  the 
average  clause,  improved  construction,  use  of  sprinklers,  etc.; 
but  it  would  seem  that  as  an  underwriting  effort  nothing  would 
so  surely  accomplish  the  purpose  and  bring  the  conflagration 
hazard  home  to  the  American  people  as  the  proposition  to  issue 
the  fire-insurance  policy  on  the  limited  liability  plan.* 

In  the  plan  for  conflagration  liability  outlined  above,  the 
word  "  conflagration "  is  used  in  its  broad  or  European  sense, 
that  is,  any  fire  spreading  beyond  the  building  in  which  it 
originates.  Inordinate  losses  on  the  part  of  any  single  insurance 
company,  due  to  wide-spread  conflagration  in  any  city,  are  sup- 
posed to  be  already  provided  against  through  the  limitation  of 
risks  written  by  that  company  within  each  defined  area  or 
"fire  block"  into  which  each  city  is  divided. 

Relation  of  Insurance  to  Building  Construction.  —  The 
fundamental  idea  of  fire  insurance  is  the  selling,  by  underwriters, 
of  indemnity  for  fire  loss  on  property  as  they  find  it.  Strictly 
speaking,  the  combustible  or  non-combustible  character  of  the 
risk,  its  exposure,  and  its  protection  or  non-protection  by  de- 
partmental or  auxiliary  means,  are  questions  for  the  insured  to 
care  for.  The  insurance  company  will  insure  the  risk  whatever 
the  hazard  from  each  or  all  of  these  factors,  provided  the  insured 
pay  a  sufficiently  large  rate  to  justify  the  risk  assumed  by  the 
insurer. 

In  order  to  determine  the  rate  at  which  the  property  may  be 
insured  at  a  profit,  a  survey  of  the  property  becomes  necessary. 
Such  survey  must  take  into  consideration  all  attendant  items 

*  See  "Conflagrations  from  an  Underwriting  Standpoint,"  by  Edward  R. 
Hardy,  N,  Y,  Fire  Insurance  Exchange,  in  Journal  of  Fire,  September,  1906. 


62  FIRE   PREVENTION   AND   FIRE   PROTECTION 

of  risk,  as  circumscribed  by  the  practice  of  rating  under  the 
particular  schedule  in  force,  and  increases  or  reductions  in  the 
rate  are  made  in  accordance  with  the  findings.  From  this 
point  on,  the  whole  question  of  insurance  becomes  simply  a 
bargain  between  the  company  and  the  property  owner.  The 
company  virtually  offers  to  lease  from  the  insured  stipulated 
improvements  in  construction,  such  as  fire  doors  or  shutters, 
enclosures  to  vertical  openings,  parapet  walls  above  the  roof, 
etc.,  or  improvements  in  protective  features,  such  as  sprinklers, 
automatic  alarms,  watchman  service,  etc.  It  is  entirely  optional 
with  the  insured  whether  or  not  he  make  these  improvements 
to  lease  to  the  company.  The  determining  factor  almost  in- 
variably becomes  a  comparison  in  dollars  and  cents  between 
the  interest  on  the  cost  of  such  improvements,  and  the  price  at 
which  he  can  lease  them  to  the  insurance  company,  in  other 
words,  the  rebate"  in  premiums  which  the  insurance  company 
will  allow  for  their  installation.  (This  method  of  reasoning  is 
not  true  of  mutual  companies,  who  will  only  insure  their  members 
when  strictly  complying  with  stated  requirements.) 

This  financial  relation  between  the  cost  of  improvements  and 
their  rebate  value  thus  becomes  the  crux  of  insurance  whether 
the  building  alone  is  considered,  or  contents  as  well;  and  it  will 
be  the  purpose  of  the  following  paragraphs  to  show  this  mone- 
tary relation  as  plainly  as  may  be  possible,  particularly  as  re- 
gards the  correction  of  structural  deficiencies  and  the  installation 
of  protective  equipment. 

Example  of  Sprinkler  Equipment.  — The  following  actual 
example  of  the  rebate  value  of  a  sprinkler  equipment  in  a  build- 
ing within  the  congested  area  of  a  large  city  is  by  no  means 
typical,  but  serves  admirably  to  show  how  vitally  protective 
equipment  may  influence  insurance  rates. 

Building.  —  The  insurance  rate  on  building  before 
the  installation  of  sprinkler  equipment  was,  per 

$100 $.32 

The  installation  removed  the  10  per  cent,  added  to  rate 

after  the  San  Francisco  fire .03 

729 
The  allowance  for  sprinkler  installation  was  47J  per 

cent .14 

Making  net  rate  with  sprinkler  allowance .15 


THEORY   AND   PRACTICE   OF   FIRE    INSURANCE         63 

The  saving  in  insurance  rate  due  to  installation  was 

therefore $ .  17 

The  building  was  valued  at  $300,000. 

Insurance  carried  $200,000. 

Annual  saving  in  insurance  charges  due  to  installation 

of  sprinkler  equipment 340.00 

Contents.  —  The  insurance  rate  on  contents  before 

installation  of  sprinkler  equipment  was 1.37 

Removal  of  added  10  per  cent .14 

1.23 
The  allowance  for  sprinkler  installation  was  47  J  per 

cent .58 

Making  net  rate  with  sprinkler  allowance .65 

The  saving  in  insurance  rate  was  therefore .72 

The  contents  were  valued  at  $902,500. 
Insurance  carried  (100  per  cent,  co-ins.)  $900,000. 
Annual  saving  in  insurance  charges  on  contents  ....      $  6,480.  00 
Tptal  annual  saving  in  insurance,  building  and  con- 
tents           6,820. 00 

The  total  cost  of  sprinkler  equipment  was 14,500.  00 

Interest  on  investment,  not  considering  repairs  or  depreciation, 
47  per  cent. 

Example  of  Typical  Building.*  —  Building.  The  example 
selected  represents  a  somewhat  typical  loft  building, '  similar 
to  those  now  being  erected  in  different  parts  of  the  country,  but 
especially  in  the  city  of  New  York,  on  Manhattan  Island,  where 
some  hundreds  of  a  like  nature  already  exist.  The  building  is 
assumed  to  occupy  a  lot  50  by  100  feet  in  area,  to  be  twelve 
stories  and  basement  in  height,  and  of  plan,  frontage  and  ex- 
posure as  shown  in  Fig.  2.  The  building  is  assumed  to  be  of 
modern  steel  construction  with  standard  brick  walls,  concrete 
floors  and  roof,  and  properly  protected  columns. 

Gross  area  5000  square  feet.  Net  area  of  one  floor  4750  square 
feet.  Height,  160  feet.  Cubic  contents,  760,000  cubic  feet. 

P  *  The  author  wishes  to  state  that  this  example  has  been  worked  out  in  all 
details  as  conscientiously  as  possible,  as  a  typical  illustrative  case,  without  any 
attempt  to  make  results  accord  with  preconceived  expectations.  The  ratings 
of  building  and  contents  were  kindly  worked  out  for  the  author  by  Mr.  Edward 
R.  Hardy  of  the  New  York  Fire  Insurance  Exchange.  Careful  estimates  of 
the  cost  of  improvements,  equipment,  etc.,  were  obtained  from  those  well 
qualified  to  make  same. 


64 


FIRE    PREVENTION    AND    FIRE    PROTECTION 


Estimated  cost  per  cubic  foot,  20  cents.     Estimated  value  of 
building,  about  $150,000. 

Occupancy.  —  It  is  assumed  that  the  building  is  owned  and 
occupied  by  a  clothing  manufacturer  who  devotes  the  lower 
stories  to  sales  purposes,  and  the  upper  stories  to  manufacturing 
purposes.  A  reasonable  valuation  of  the  contents  may  be 
taken  at  twice  the  value  of  building,  or  $300,000.* 

100  FOOT  STREET 


-50- 


40  FOOT  STREET 
FIG.  2.  —  Typical  Building  illustrating  Insurance  Charges. 

Insurance.  —  In  properties  of  this  nature  the  building  would 
ordinarily  be  insured  with  the  80  per  cent,  co-insurance  clause 
for  a  three-year  period,  the  rate  for  which  would  be  2i  times  the 
annual  rate.  This  is  equivalent  to  a  discount  of  one-sixth  the 
annual  rate.  Amount  of  insurance  carried  $120,000. 

The  contents  would  also  be  insured  with  the  80  per  cent,  co- 
insurance clause,  on  which  the  straight  annual  rate  would  be 
charged.  Amount  of  insurance  carried  $240,000. 

*  This  is  by  no  means  excessive.  Insurance  records  show  that  such  a 
building  as  is  here  assumed  will  often  contain  merchandise  to  the  value  of 
three  times  the  value  of  building.  See,  also,  the  actual  example  of  sprinkler 
equipment  previously  given. 


THEORY   AND    PRACTICE    OF    FIRE    INSURANCE         65 

Exposure  Hazard.  —  The  front,  facing  a  100-foot  street,  and 
the  blank  wall  on  one  side  will  involve  no  exposure  charge.  The 
rear,  facing  a  40-foot  street,  and  the  side  wall  and  court  over- 
looking adjacent  five-story  non-fire-resisting  buildings,  will  both 
involve  exposure  charges. 

Structural  Deficiencies,  etc.  —  For  the  purpose  of  illustration, 
it  will  be  assumed 

(a)  That  the  exposure  hazard  is  not  cared  for,  but  that  ordi- 
nary wood  and  glass  windows  only  are  used  throughout. 

(6)  That  vertical  openings  are  not  cut  off  at  each  story  by 
standard  enclosures,  but  that  the  stairway  is  enclosed  by  hollow 
tile  partitions  and  wood  doors,  and  that  elevators  are  surrounded 
by  open  grille  work. 

The  object  of  this  inquiry,  then,  is  to  see  how  the  remedy- 
ing of  the  above-stated  structural  deficiencies  will  operate  as 
commercial  propositions. 

Equipment.  —  It  is  also  assumed  that  no  fire  protection  equip- 
ment of  any  kind  is  provided.  The  inquiry  will  also  cover, 
therefore,  the  monetary  value  of  different  forms  of  auxiliary 
equipment. 

Insurance  Rates.  —  The  Building,  under  the  conditions 
stated,  would  be  rated  as  follows. 

Key  rate..  .  . $.10 

Skeleton  construction 02 

Height 06 

Merchandise  above  seventh  floor 29 

Concrete  arches 04 

Wooden  flooring 05 

Open  elevators  and  stairway 06 

Manufacturing  employes 10 


Total 72 

Hazard  charge,  clothing  manufacturing 05 


Total 77 

Exposure 46 


1.23 

Deducting  for  co-insurance  gives  a  final  rate  of       .  423 
The  contents,  under  the  same  conditions,  would 

have  a  final  rate  of 1.  972 


66 


FIRE   PREVENTION   AND   FIRE   PROTECTION 


Rates  (figured  for  each  equipment  item  separately  and  not 
cumulatively)  for  the  remedying,  in  standard  manner,  of  the 
structural  deficiencies  above  stated,  and  for  the  installation, 
in  standard  manner,  of  various  forms  of  auxiliary  equipment, 
may  be  tabulated  for  building  and  contents  as  follows: 


Build- 

Con- 

ing. 

tents. 

Conditions  as  above  stated,  i.e.,  with  non-standard  floor  openings, 

exposure  hazard  uncared  for,  and  no  fire-protection  equipment.  . 

.423 

.972 

Same  as  above,  except  that  exposure  hazard  has  been  remedied  .  . 

.358 

.844 

*  Same,  with  exposure  hazard  and  floor  openings  both  remedied. 

.330 

.446 

Same  as     but  with  standpipe  installation  

.310 

.360 

Same  as     but  with  standard  fire  pails 

318 

380 

Same  as     but  with  automatic  alarm  installation  

.302 

369 

Same  as     but  with  watchman  and  approved  watch  clock  

.329 

429 

Same  as     but  with  automatic  sprinkler  installation  .... 

165 

723 

Exposure  Hazard.  —  According  to  the  above  table  of  rates 
the  remedying  of  the  exposure  hazard  would  effect  annual 
savings  in  insurance  premiums  as  follows: 

On  building,  |  X  .065  X  $120,000,  or  $  65.00 
On  contents,          .128  X    240,000,  or    307.20 


Total  saving $372.20 

To  effect  this  saving,  the  following  improvements  would  be 
necessary : 

On  rear  wall,  the  installation  of  standard  fire  shutters  or  metal 
and  wire  glass  windows.  For  an  exposure  distant  30  feet  or 
over,  either  installation  would  be  satisfactory. 

On  side  wall  and  court  windows,  standard  fire  shutters  or 
metal  and  double-glazed  wire  glass  windows  for  all  openings 
within  30  feet  of  adjacent  building  or  roof  thereof,  and  fire 
shutters  or  single-glazed  wire  glass  windows  for  all  openings 
more  than  30  feet  above  roof  of  adjoining  building. 

It  is  assumed  that  the  indented  court  walls  are  pierced  at 
each  floor  by  four  windows  at  stairs  and  elevators,  and  by  two 
windows  at  each  end  of  court,  —  also  that  each  floor  overlooking 
the  roof  of  adjoining  building  has  four  windows  in  the  side  wall. 
This  will  make  13  X  8  windows  in  court,  and  7X4  windows  in 
side  wall,  or  a  total  of  132  openings.  Averaging  these  at  21 
square  feet  each  will  equal  2772  square  feet.  The  cheapest 


THEORY   AND   PRACTICE   OF   FIRE   INSURANCE        67 

method  of  protecting  these  openings  is  by  means  of  tin-clad 
shutters,  the  installation  of  which  would  cost  about  $832.00. 

The  rear  wall  will  have  12  X  8  =96  openings,  or  2016  square 
feet  of  window  surface.  These  windows  might  also  be  covered 
with  tin-covered  shutters,  but  as  the  appearance  would  be 
unsightly,  we  will  assume  metal  and  wire  glass  windows,  which 
would  cost  approximately  $2000,  allowing  some  salvage  on  the 
ordinary  wood  windows.  The  total  cost  of  improvement  would, 
therefore,  equal  $2832;  or,  an  investment  of  $2832  would  be 
placed  with  the  insurance  companies,  upon  which  an  allowance, 
or  a  dividend  of  $372,  would  be  paid  yearly.  In  other  words,  if 
the  owner  wished  to  secure  a  gross  ten  per  cent,  on  his  investment 
to  cover  interest  and  depreciation,  the  insurance  companies 
would  still  pay  him  an  additional  three  per  cent,  profit. 

Vertical  Openings.  —  If,  as  a  second  step,  the  owner  were 
to  investigate  the  making  of  stair  and  elevator  enclosures  of 
standard  construction,  the  proposition  would  work  out  about  as 
follows : 

The  annual  savings  in  insurance  premiums  would  be 

On  building,  J  X  .028  X  $120,000,  or     $  28.  00 
On  contents,          .398  X    240,000,  or       955.00 


Total  saving $983.  00 

To  effect  this  saving  it  would  be  necessary  to  substitute  auto- 
matic fire  doors  at  all  stair-well  openings,  and  to  substitute,  for 
example,  6-inch  tile  partitions  and  standard  doors  around  the 
elevators,  in  place  of  the  open  grille  work.  The  cost  of  such 
improvements  would  be  approximately  $4100;  hence  in  this  case 
the  owner  would  realize  24  per  cent,  on  his  investment. 

Fire  Protection  Equipment.  —  Assuming  that  both  of  the 
structural  deficiencies  previously  described  would  be  remedied, 
so  as  to  make  the  building  of  standard  construction,  the  intelli- 
gent owner  would  next  investigate,  as  a  natural  sequence,  the 
question  of  fire  protection  equipment.  For  the  protection  of 
contents,  auxiliary  equipment  is  often  the  most  vital  consider- 
ation involved  in  fire  protection,  as  is  pointed  out  at  more 
length  in  Chapter  XXIX;  so  that  the  question  of  fire  protection 
equipment  becomes  not  only  a  matter  of  insurance  rates,  but  a 
matter  of  good  business  policy  from  other  standpoints  quite  as 
important  as  mere  insurance  rates.  Insurance,  alone,  seldom 


68 


FIRE   PREVENTION   AND   FIRE   PROTECTION 


compensates  for  the  actual  fire  losses  sustained  in  mercantile 
buildings  and  their  contents,  and  still  less  can  insurance  cover 
the  inevitable  interruption  to  business,  the  loss  of  orders  and 
possibly  of  customers,  or  losses  in  rents,  etc. 

Possibilities  in  the  line  of  fire  protection  equipment  would 
include  standpipe  with  hose  reels,  etc.,  —  which  would  be  re- 
quired by  law  in  many  cities  —  fire  pails,  automatic  alarms, 
watchman  with  approved  watch  clock  or  with  central  station 
supervision,  and  automatic  sprinklers.  Of  these,  equipments  of 
standpipe,  fire  pails  and  sprinklers  would  involve  the  expense 
of  installation  only  (unless  sprinklers  were  equipped  with  cen- 
tral station  supervision)  plus  the  cost  of  repair  or  maintenance. 
With  automatic  alarms  and  watchman  service,  however,  fixed 
annual  charges  must  be  considered.  Automatic  alarms  involve 
the  expense  of  installation  and  the  added  expense  or  rental  for 
maintenance.  Watchman  service  involves  but  a  slight  expense 
for  the  installation  of  stations  and  the  purchase  of  a  clock,  but 
the  weekly  wages  of  a  watchman  operate  as  the  maintenance 
expense  of  this  form  of  protection.  Also  the  desirability  of 
providing  a  watchman  to  guard  against  burglary  is  a  valuable 
feature  of  protection  which  cannot  be  represented  in  any  mone- 
tary comparisons.  If  central  station  supervision  is  provided, 
the  reliability  of  the  watchman  service  is  greatly  increased,  but 
the  expense  of  maintenance  increases  also.  Bearing  these  facts 
in  mind,  the  various  forms  of  equipment  may  be  tabulated  as 
to  allowances  on  premiums,  cost,  etc.,  as  follows,  each  item  being 
rated  separately,  without  reference  to  any  other  method  of 
protection : 


-i  a 

A 

"S  c 

i  fl 

_^ 

°  bfl 

"*  °  ^ 

*    0    02 

is  S| 

—   . 

£.2  "3 

||| 

'blol^ 

|  a  § 

.2  a 

Cost  of  equipment  . 

c*  o  g 

a  £  3 

2  O-O 

111 

||  I 

|p 

Hl 

ill 

1-4 

CG  ra 

h-  1 

CO  W 

£ 

Standpipe.  .  . 

IX.02 

$20 

.086 

$206 

$226 

$2400 

9 

Fire  pails  

gX.012 

12 

.066 

158 

170 

$840 

20 

Automatic 

Installation,             $11,500 

alarm.  .  . 

IX.  028 

28 

.077 

185 

213 

Yearly  maintenance,    215 

Watchman 

gx.ooi 

1 

.017 

41 

42 

Installation,                      60 

and  clock  . 

Yearly  maintenance,    780 

Sprinklers..  . 

IX.  165 

165 

.723 

1735 

1900 

$9353 

20 

CHAPTER  IV.  ^ 

1  SLOW-BURNING   OR   MILL   CONSTRUCTION. 

R*- 

Slow-burning  Construction.  —  This  term  is  commonly 
applied  to  that  type  of  mill  and  storehouse  construction  which 
has  been  so  successfully  developed,  especially  in  the  New  Eng- 
land states,  by  the  Associated  Factory  Mutual  Fire  Insurance 
Companies.  Its  extended  use  for  such  buildings  as  textile 
factories,  paper  mills,  machine  shops,  and  other  classes  of  manu- 
facturing and  storage  buildings  has  been  largely  due  to  the  great 
improvements  wrought  by  the  late  Mr.  Edward  Atkinson,  for- 
merly president  of  the  Boston  Manufacturers  Mutual  Fire  In- 
surance Company,  and  director  of  the  Insurance  Engineering 
Experiment  Station;  and  it  has  been  found  so  efficient  from  the 
standpoints  of  cost,  maintenance,  and  security,  that  no  apology 
is  needed  for  including  this  construction  in  a  handbook  on  fire 
protection. 

The  basic  idea  of  slow-burning  construction  is  to  provide  a 
maximum  of  fire  protection  at  a  minimum  cost,  and  this  has  been 
so  well  accomplished  that  it  is  questionable,  to  say  the  least,  in 
how  far  the  added  expense  of  a  thoroughly  fire-resisting  building 
has  been  warranted  when  the  structure  has  been  isolated,  and 
suited  to  this  type  of  construction.  We  say  has  been  warranted, 
for.  as  is  pointed  out  elsewhere,  lumber  has  so  increased  in 
price  of  late  years,  and  thoroughly  fire-resisting  concrete  con- 
struction has  so  lowered  in  cost  in  the  same  period,  that  it 
is  not  improbable  that  the  two  constructions,  slow-burning  and 
concrete,  will  be  very  nearly  alike  in  cost  in  the  not  distant 
future.  ^^ 

Necessity  for  Fire  Protection  Appliairffes.  —  Mill  con- 
struction has  been  designated  slow-burning,  because,  although 
largely  composed  of  combustible  materials,  intelligent  use  and 
sufficient  mass  have  greatly  lessened  the  chance  of  the  rapid 
spread  of  fire,  or  the  probability  of  serious  structural  damage 
before  the  fire  can  be  brought  under  control  through  the  equip- 
ment or  fire  protection  devices  which  should  always  accompany 

69 


70  FIRE   PREVENTION    AND    FIRE   PROTECTION 

this  type  of  construction.  Such  equipment  includes  watch- 
man's service,  automatic  sprinklers,  fire  pails,  hose,  pumps, 
and  hydrants,  besides  an  efficient  private  fire  brigade,  all  of 
which  subjects  are  discussed  at  length  in  later  chapters.  It  is 
these  safeguards,  coupled  with  the  better  adaptation  of  all  manu- 
facturing or  storage  buildings  to  the  risks  inherent  in  their 
occupancy,  that  have  caused  the  losses  in  the  older  Factory 
Mutual  Fire  Insurance  Companies  to  average  four  cents  per 
hundred  dollars  annually,  as  compared  with  sixty  cents  in  other 
property  (or  a  ratio  of  one  to  fifteen) ,  while  the  average  cost  of 
insurance  to  the  owners  of  approved  factories  has  been  reduced 
to  less  than  seven  cents.  See  also  Chapter  XXX  for  further 
information  regarding  insurance  losses,  costs,  etc.,  in  sprinklered 
risks. 

A  wonderful  illustration  of  the  slow-burning  qualities  of  slow- 
burning  construction  was  afforded  by  the  fire  which  destroyed 


FIG.  3.  —  Fire  in  Mill  Construction  Warehouse  of  the  George  Irish  Paper 
Corporation,  Buffalo,  N.  Y. 

the  storage  warehouse  of  the  George  Irish  Paper  Corporation, 
at  Buffalo,  N.  Y.,  January  16,  1911.  The  building  was  six 
stories  in  height,  70  by  200  feet  in  area,  and  of  mill  construction 
without  sprinklers  or  other  special  fire  protection  equipment. 


SLOW-BURNING   OR   MILL    CONSTRUCTION  71 

Because  of  the  type  of  construction  of  the  building,  and  the 
great  weight  of  the  paper  stock  known  to  -be  stored  therein,  the 
firemen  flatly  refused  to  enter  the  structure,  so  that  the  flames 
were  fought  entirely  from  the  outside.  Fig.  3  illustrates  the 
progress  of  the  fire  "36  hours  after  the  fire  started,  during  which 
time  many  streams  of  water  had  been  continuously  thrown 
upon  it.  The  fire  raged  for  upwards  of  80  hours  and  was  the 
longest  fire  known  in  the  City  of  Buffalo,  —  which  fact  testified 
to  the  great  strength  of  our  warehouse."*  It  should  be  noted 
in  the  photograph  that,  after  36  hours  of  fire,  the  front  windows 
in  the  top  story  are  practically  intact.  No  better  example  of 
"  slow-burning  "  construction  could  possibly  be  given. 

An  example  of  an  ideal  mill  plant  and  its  layout  of  fire  protec- 
tion is  given  in  Fig.  4.f  This  plan  of  fire  protection,  may,  in  a 
general  way,  be  adapted  to  any  given  plant,  but  only  in  con- 
sultation with  insurance  authorities.  It  may  comprise  more 
protection  than  is  needed  for  some  plants,  and  less  than  is  needed 
for  others.  The  extent  and  capacity  of  fire  apparatus  depend 
upon  construction,  height,  area,  occupancy,  arrangement,  and 
surroundings  of  plant.  The  more  important  elements  of  fire 
protection  are  as  follows: 

^  1.  Water  Supply. — a.  Public  water  supplied  by  gravity 
at  good  pressure  and  ample  quantity  is  best.  A  pressure  of  about 
60  pounds  maintained  in  the  mill  yard  while  1000  to  1500  gallons 
or  more  are  flowing,  is  ordinarily  considered  excellent.  Such  a 
public  water  supply  is  always  preferred  to  an  elevated  tank. 

b.  Pump  supply  from  one  or  two  Underwriter  pumps  accord- 
ing to  the  size  of  the  plant.     Pumps  to  draw  from  supply  capable 
of  furnishing  water  during  a  fire  of  long  duration  and  independent 
of  the  public  water  works. 

c.  Steam  boilers  should  have  two  absolutely  independent 
sources  of  water  supply.     A  direct  connection  from  fire  pump 
to  the  boilers  is  often  desirable  and  may  be  considered  as  one 
of  these.     The  steam  supply  to  pump  should  be  taken  off  behind 
a  valve  or  valves  controlling  supply  to  engines  or  other  factory 
service,  and  all  controlling  valves  should  be  in  the  boiler  house. 
The  pipe  should  be  so  located  that  it  can  not  be  broken  by  falling 
walls  or  other  accident  at  a  fire. 

2.  Hydrants.  —  Placed  at  sufficiently  frequent  intervals  so 
that  the  full  capacity  of  the  water  supply  available  may  be  con- 
centrated at  any  point  of  the  plant  without  the  use  of  long  lines 
of  hose. 

*  From  information  furnished  by  the  George  Irish  Paper  Corporation, 
t  From  report  "Slow-burning  or  Mill  Construction,"  issued  by  the  Boston 
Manufacturers  Mutual  Fire  Insurance  Company. 


72 


FIRE   PREVENTION   AND   FIRE   PROTECTION 


c!-way  Hydrant 
•Standard  Hose  f 


J 


One  Suction  Pipe  fbr  each n 
pump;  supply  from  lar^e 
•eservoir.pond  or, river. 


fein.PluJ 

! 
I 


eioP.uj 


\                          xi.P  G  (Control!  n*  Circuit) 

Two  750  or  1060  Gallon    •              %              imlMJi|4|il||i||  f  f  HM  — 

8  in  discharge  p  pe  for                      %                 .  T 
each  pump.                                      *     \            $, 

y  Two  Check  Vi  in  brick  pit 

j  8  .u-  \»        i  £ 

-      PG.-'                      .-». 

g  If1  tap    -^ 

*N  Two  O.S&Y  Gates   Kl 

^J  c               •    • 

'3  /-A.  S.  Riser. 

w 

"  When  Good  Public  Water  Supply                   ^ 
or  lar^e  elevated  reservoir  cannot     Tv""'"^*' 

-r" 

3(1  .E  I     H  >U  J! 

r- 

sis 

be  made  available.,  a  lar^e  tank         "'        ;  *N  7 

| 

with  bottom  25  ft.  or  more  above         [            **IR""  % 

l== 

highest  roof  sprovded.                      !^x 

-      2-  way  Mydrant 
Standard  Hose  Mouse  [^|                               Q  jn. 

JkOTB 

/ay  "Roof  Hydrant 

0< 

f           ^= 

H   V 

1  1    » 

^TT"                  ^' 

CLOSET 

m 

•TOWER                  FANRM.     =^~ 

^       FHoi 

•fill                                   ;' 

C                         mm    mm      m     ft     •    •     -     H     LI      i-     1 

J^_                 "jj! 

Jl": 

|f 

L 

P           P  C  CE 

1  Z 

'I 

r 

i> 

i 

4 

ru 

.1 

•"r 

fin?15 

-• 

J 

u« 

"S  i      ^ 

— 

V 

1'  ™ 

—  «l| 

— 

a 

2r     — 

"™"  s^' 

= 

.S 

s!  t 

feS 

= 

"u 

«S  ^« 

<i> 

J 

is 

8  in. 

IPG 

.Indicator  Post  Gate 

.IPG. 

.P.O.                  >I.PG 

2-way  Hydrant  I.P.G.  '    -WE- way  Hydrant  '      E-way  Hydrant  & 

Standard  Hose  House  (Controlling Circuit)  Standard  hose  Hoi 

Fia.  4.  —  Ideal  Mill  Plant  and  Lay-out  of  Fire  Protection. 


SLOW-BURNING   OK   MILL    CONSTRUCTION  73 


=0=== 


•DryPipe 

on  fon^  B 


Sc^e  OF  recr  IS3  2-wa>,     f 

;-i  .-40.         60         ao    i !^°  "        Standard  Hose  Mou; 


"!gf   8'n-p|u1 


FIG.  4.  —  Ideal  Mill  Plant  and  Lay-out  of  Fire  Protection  (contimted). 


74  FIRE    PREVENTION    AND    FIRE    PROTECTION 

Generally  hydrants  at  intervals  of  about  200  feet  are  re- 
quired, two-way  hydrants  to  have  at  least  5-inch  gate  opening 
and  barrel,  and  hydrants  with  more  than  two  outlets  to  have  a 
6-inch  gate  opening  and  barrel,  and  independent  gates  for  each 
outlet. 

Roof  hydrants  are  of  value  in  fighting  outside  fires  either 
in  adjoining  properties  or  where  buildings  adjoin  one  another  in 
a  crowded  mill  yard. 

Hose  standpipes  properly  located  are  of  great  value  in  build- 
ings of  over  two  or  three  stories,  especially  when  fire  is  beyond 
control  of  sprinklers. 

3.  Sprinklers.  —  a.   Automatic    sprinklers    throughout    all 
rooms,  including  storehouses,  elevators,  and  stairs,  all  closets, 
inclosures,  etc.,  also  to  be  covered.      There  should  be  no  part 
of  the  floor  area,  ceilings,  or  roofs  without  ample  protection,  and 
heads  must  be  so  spaced  as  to  satisfactorily  cover  all  places.     It 
is  required  that  detail  sprinkler  plans  showing  protection  pro- 
posed be  submitted  to  the  Insurance  Companies  before  the  in- 
stallation begins.     Dry  pipe  valves  should  be  used  only  when 
it  is  impracticable  to  heat  the  building,  as  their  installation  con- 
siderably increases  the  time  before  discharge  of  water  on  the  fire, 
and  therefore  correspondingly  weakens  the  protection. 

b.  Each  sprinkler  connection  into  buildings  to  be  provided 
with  outside  post  indicator  gate,  safely  located,  and  sufficient 
connections  are  required  for  large  areas  so  that  there  may  not 
be  over  200  sprinklers  in  one  room  on  a  single  6-inch  supply. 

Pipe  connections  into  buildings  should  not  be  less  than 
6-inch,  even  when  supplying  risers  of  smaller  size,  except  in 
especial  cases  where  only  30  or  40  heads  are  supplied  per  floor 
in  low  buildings. 

4.  Yard  Pipes.  —  Of  ample  size  to  carry  the  water  available 
to    sprinklers   and  hydrants   without   serious   loss   of  pressure. 
For  the  mill  shown,  an  8-inch  loop  pipe  is  sufficient.     Should 
the  loop  not  be  practicable,  the  pipe  in  a  part  of  the  yard  system 
may  need  to  be  10-inch.     For  large  mills  with  extended  yard 
area,  10-inch  pipe  or  even  larger  may  be  necessary.     Class  E 
pipe  N.  E.  W.  W.  Association  is  required,  or  class  C  of  the  Ameri- 
can Water  Works  Association  standard. 

Pipes  to  be  in  such  location  that  hydrants  and  post  indicator 
valves  may  be  at  a  good  distance  from  the  walls  of  very  high 
buildings  or  those  of  large  area. 

Pump  check  valves  should  be  safely  located  below  floor 
level.  The  brick  well  is  merely  to  make  it  more  readily  accessible. 

Circuit-controlling  valves  are  advisable  at  intervals  in  ex- 
tensive yards  so  as  not  to  necessitate  shutting  off  the  entire  yard 
system  at  one  time  in  case  of  repairs  or  alterations. 

5.  Hose.  —  a.    Outside    equipment    to    consist    of    2|-inch 
Underwriter  cotton  rubber-lined  hose  of  one  of  the  approved 
brands    which,    together    with    spanners,    If-inch    Underwriter 
nozzles,  axes,  bars,  lanterns,  etc.,  must  be  kept  in  the  hose  houses. 
(See  Chapter  XXXV.) 


SLOW-BURNING    OR    MILL    CONSTRUCTION  75 

b.  Inside  equipment  to  be  provided  in  all  rooms,  fed  pref- 
erably from  a  system  of  small  standpipes  independent  of  sprink- 
ler system,  that  it  may  be  available  if  the  sprinklers  are  shut  off 
on  account  of  accident  or  after  they  are  shut  off  at  fire  to  save 
water  damage.  In  some  cases  it  may  be  attached  to  1-inch 
nipples  from  sprinkler  pipes  not  less  than  2^  inches  in  diameter, 
but  is  then  not  available  at  a  time  when  \t  may  be  most  needed. 
Hose  and  couplings  to  be  for  l|-inch  Underwriter  linen  hose  and 
nozzles  f-inch  smooth  bore. 

c.  For  tower  standpipes  2 f-inch  best  Underwriter  linen  hose 
of  approved  brands  to  be  provided. 

What  Mill  Construction  is.  —  1.  "Mill  construction  con- 
sists in  so  disposing  the  timber  and  plank  in  heavy  solid  masses 
as  to  expose  the  least  number  of  corners  or  ignitable  projections 
to  fire,  to  the  end  also  that  when  fire  occurs  it  may  be  most 
readily  reached  by  water  from  sprinklers  or  hose. 

2.  "It  consists  in  separating  every  floor  from  every  other  floor 
by  incombustible  stops  —  by  automatic  hatchways,  by  encasing 
stairways  either  in  brick  or  other  incombustible  partitions  — 
so  that  a  fire  shall  be  retarded  in  passing  from  floor  to  floor  to 
the  utmost  that  is  consistent  with  the  use  of  wood  or  any  material 
in  construction  that  is  not  absolutely  fireproof. 

3.  "It  consists  in  guarding  the  ceilings  over  all  specially  hazard- 
ous  stock   or   processes   with   fire-retardent   material   such    as 
plastering  laid  on  wire-lath  or  expanded  metal  or  upon  wooden 
dovetailed-lath,  following  the  lines  of  the  ceiling  and  of  the  tim- 
bers without  any  interspaces  between  the  plastering  and  the 
wood;   or  else  in  protecting  ceilings  over  hazardous  places  with 
asbestos  air  cell  board,  sheet  metal,  Sackett  wall  board  or  other 
fire-retardent. 

4.  "It  consists  not  only  in  so  constructing  the  mill,  workshop, 
or  warehouse  that  fire  shall  pass  as  slowly  as  possible  from  one 
part  of  the  building  to  another,  but  also  in  providing  all  suitable 
safeguards  against  fire."* 

What  Mill  Construction  is  not.  —  Mr.  Atkinson  has  stated 
that,  following  a  widely  published  article  by  him  describing  and 
illustrating  mill  construction,  so  many  totally  wrong  applications 
of  the  principles  he  enunciated  were  made,  resulting  in  examples 
which  gave  fire  "the  freest  and  quickest  course  from  cellar  to 
attic  in  such  a  way  as  to  be  most  fully  protected  from  water," 
that  he  was  obliged  to  print  and  reprint  many  times  a  supple- 

*  Edward  Atkinson. 


76  FIRE    PREVENTION    AND    FIRE    PROTECTION 

mentary  article  entitled  "What  Mill  Construction  is  Not/'  as 
follows : 

"  1.  Mill  construction  does  not  consist  in  disposing  a  given 
quantity  of  materials  so  that  the  whole  interior  of  a  building 
becomes  a  series  of  wooden  cells ;  being  pervaded  with  concealed 
spaces,  either  directly  connected  each  with  the  other  or  by  cracks 
through  which  fire  may  freely  pass  where  it  cannot  be  reached 
by  water. 

2.  It  does  not  consist  in  an  open-timber  construction  of  floors 
and  roof  resembling  mill  construction,  but  which  is  of  light  and 
insufficient  size  in  timbers  and  thin  planks,  without  fire  stops  or 
fire  guards  from  floor  to  floor. 

3.  It  does  not  consist  in  connecting  floor  with  floor  by  com- 
bustible wooden  stairways  encased  in  wood  less  than  two  inches 
thick. 

4.  It  does  not  consist  in  putting  in  very  numerous  divisions 
or  partitions  of  light  wood. 

5.  It  does  not  consist  in  sheathing  brick  walls  with  wood, 
especially  when  the  wood  is  set  off  from  the  wall  by  furring,  even 
if  there  are  stops  behind  the  furring. 

6.  It  does  not  consist  in  permitting  the  use  of  varnish  upon 
woodwork  over  which  a  fire  will  pass  rapidly. 

7.  It  does  not  consist  in  leaving  windows  exposed  to  adjacent 
buildings  unguarded  by  fire-shutters  or  wired  glass. 

8.  It  is  dangerous  to  paint,  varnish,  fill,  or  encase  heavy 
timbers  and  thick  plank  as  they  are  customarily  delivered,  lest 
what  is  called  dry  rot  should  be  caused  for  lack  of  ventilation 
or  opportunity  to  season. 

9.  It  does  not  consist  in  leaving  even  the  best-constructed 
building  in  which  dangerous  occupations  are  followed  without 
automatic  sprinklers,   and  without  a  complete  and   adequate 
equipment  of  pumps,  pipes,  and  hydrants. 

10.  It  does  not  consist  in  using  any  more  wood  in  finishing 
the  building  after  the  floors  and  roof  are  laid  than  is  absolutely 
necessary,  there  being  now  many  safe  methods  available  at  low 
cost  for  finishing  walls  and  constructing  partitions  with  slow- 
burning  or  incombustible  material.'' 

Limitations  of  Mill  Construction.  —  Before  attempting 
to  adapt  mill  construction  to  a  proposed  building,  engineers 
and  architects  should  carefully  study  the  limitations  of  the 
type,  and  give  due  consideration  to  the  purposes  for  which  it 


SLOW-BURNING    OR    MILL   CONSTRUCTION  77 

is  devised.  Factory  or  storage  buildings,  if  in  congested  areas, 
should  invariably  be  fully  fire-resisting,  if  possible  under  the 
limitations  of  cost.  Mill  construction,  also,  should  ordinarily 
not  exceed  a  height  of  fifty  feet,  or  four  stories,  as  outside  hose 
streams  are  not  efficient  above  that  altitude. 

Slow-burning  Floor  Construction.  —  The  standard  mill 
of  the  Factory  Mutual  Fire  Insurance  Companies  (see  Fig.  10) 
was  planned  with  heavy  beams  eight  to  eleven  feet  on  centers, 
of  continuous  spans  from  wall  to  post  or  post  to  post  of  from 
twenty  to  twenty-five  feet.  Floors  must  be  designed  to  care 
for  weight,  deflection,  and  vibration.  Longitudinal  girders, 
supported  by  posts  and  carrying  beams  Jour  feet  or  less  on  centers 
are  not  approved,  as  such  construction  not  only  adds  to  the 
exposed  surface  of  wood  used,  but  the  beams  obstruct  the  action 
of  sprinklers,  and  prevent  the  sweeping  of  a  hose  stream  from 
one  side  of  the  mill  to  the  other.  The  ordinary  "  light  joisted" 
type  of  floor,  as  shown  in  Fig.  5,  should  never  be  used  in  any 

C\  in  Boards,  single  or  double 


Girder  or  truss  member- 
FIG.  5.  —  Undesirable  Light-joisted  Floor. 

building  pretending  to  the  least  degree  of  fire-resistance.  In 
this  type  the  joists  are  two  or  three  inches  thick,  spaced  ten  to 
sixteen  inches  centers.  If  sheathed  or  " ceiled"  on  the  under 
side  of  joists,  the  construction  is  even  still  more  dangerous,  as 
the  concealed  spaces  thus  formed  provide  inaccessible  lodgment 
for  fire. 

Approved  mill  construction  floors  are  illustrated  in  Figs.  6 
and  7.  In  the  former  the  plank  floor  is  laid  directly  on  the 
beams,  usually  spaced  not  over  10  feet  on  centers.  In  Fig.  7, 
the  posts  and  hence  the  girders  are  widely  spaced,  necessitating 
the  use  of  purlins  to  support  the  planking. 

Note  that  an  8-inch  by  12-inch  purlin  has  an  equivalent 
amount  of  wood  to  six  2-inch  by  8-inch  joists  spaced  as  in  Fig.  5, 
and  that  the  latter  expose  108  square  inches  of  surface  to  a  fire 
as  compared  with  32  square  inches  in  the  former. 

For  the  better  seasoning  of  wood  girders,  to  prevent  dry  rot, 
etc.,  such  members  when  large  have  sometimes  been  made  of 


78 


FIRE    PREVENTION    AND    FIRE   PROTECTION 


two  timbers,  side  by  side,  bolted  together  so  as  to  leave  an  air- 
space of  an  inch  or  two  between.  This  should  never  be  done, 
as  experience  has  shown  that  not  only  does  this  practice  expose 
almost  double  the  area  of  wood  to  fire,  but  that,  when  fire  is  once 
communicated  to  such  spaces,  it  will  hold  there  a  long  time,  as 
neither  sprinklers  nor  hose  streams  can  penetrate. 

3  in. to  5  in.  Plank  grooved""' 
in.  Boards      for  Hardwood  splines 


Main  Girder  or  Timber,  6  ft.  to  10  ft.on  centres 
FIG.  6.  —  Approved  Mill  Construction  Floor,  Short  Span. 


1  in.  Boards 


3  in.toS  in.  Plank 


Girder  Timber  or  Main  Truss 
FIG.   7.  —  Approved  Mill  Construction  Floor,   Long  Span. 

For  flooring,  one  thickness  of  hard,  close-grained  floor  boards 
is  usually  laid  over  3-inch  to  5-inch  plank,  with  two  layers  of 
resin-sized  paper  between.  "In  the  best  mills  lately  built,  a 
board  flooring  has  been  laid  diagonally  or  at  right  angles  to  the 
plank,  and  over  that  a  top  floor  of  birch  or  maple  laid  length- 
wise. This  intermediate  floor  gives  great  resistance  to  the  lateral 
strain  or  vibration,  and  can  be  ordinarily  of  the  cheapest  lumber 
obtainable  of  practically  uniform  thickness,  and  is  well  worth 
the  additional  cost." 

Protection  of  Steel  Girders.  —  "In  machine  shops  and 
other  plants  requiring  exceptionally  heavy  floor  construction 
above  the  ground  level,  steel  beams  are  of  necessity  resorted  to, 
and  with  these,  wide  spacings  of  from  7  to  12 J  feet  are  main- 
tained, thus  retaining  all  the  advantages  of  the  standard  mill 
construction  except  that  of  resistance  to  fire,  provision  for  which 
when  necessary  can  be  made  by  fireproofing  as  explained  further 
on.  In  this  type,  to  obtain  unusual  stiffness  between  the  beams, 
the  floors  may  be  made  up  of  2-inch  joists  on  edge  spiked  to- 
gether closely  side  by  side,  the  thickness  of  the  floor  varying 
with  the  loads  and  span  from  5  to  8  inches  or  more.  This 


SLOW-BURNING   OR   MILL    CONSTRUCTION 


79 


floor  being  practically  a  single  unit,  provision  must  be  made 
longitudinally  for  contraction  by  making  a  continuous  joint  in 
the  under  flooring  at  intervals,  with  of  course  arrangement  for 
tying  the  building  together."  * 

Steel  girder  beams  may  be  inexpensively  protected  against 
fire  as  shown  in  Fig.  8. 


Alternate  Method 
Rods  if  used  may  be 
sharpened  and  driven  and 
fastened  with  heavy  staple. 


At  least  &  in  of  plaster 
outside  of  lath,  2  coat  work. 


Between  rods  or  channels 
wrap  lower  flange  with  piece 
of  metal  lath  to  provide  ample 
thickness  of  plaster  over  flange. 


"-  Metal  lath  to  be  well 
stapled  on  to  the  wood. 


J4  in.  rod  or  %  in 
channel  spaced  every 
18  in.  where  beam  is 
more  than  10  in  deep. 

Metal  lath  to  be  wired 
to  channel  or  rod .. 

Can  be  cut  away  for 
hangers  and  pointed  up 
after  hangers  are  in  place. 


FIG.   8.  —  Protection  of  Steel  Girders. 


Posts.  —  Timber  posts  are  far  more  reliable  under  fire  test 
than  are  unprotected  wrought-iron  or  steel  columns. 

"The  reasons  (though  in  a  much  less  degree)  which  make 
heavy  timbers  preferable  to  iron  girders,  also  make  the  use  of 
timber  pillars  desirable.  A  round  8-inch  Georgia  pine  pillar 
put  in  to  carry  safely  its  load  with  a  factor  of  safety  of  five 
might  be  burned  and  charred  in  to  the  depth  of  If  inches  over 
its  whole  surface,  thus  reducing  its  diameter  to  5^  inches,  and 
still  be  left  strong  enough  to  carry  temporarily  double  its  regular 
load,  or  to  stand  up  until  the  fire  would  be  over  and  props  could 
be  put  in  to  relieve  it."f 

The  same  argument  holds  true  of  timber  posts  vs.  unprotected 
cast-iron  columns,  in  that  the  latter  are  less  uniformly  reliable 
under  fire  test,  especially  when  suddenly  cooled  by  hose  streams. 

*  See  report  "Slow-burning  or  Mill  Construction,"  previously  referred  to. 

t  See  "Comparison  of  English  and  American  Types  of  Factory  Construc- 
tion," by  John  R.  Freeman,  in  Journal  of  Association  of  Engineering  Societies^ 
January,  1891. 


80 


FIRE   PREVENTION   AND   FIRE   PROTECTION 


Boston  Manufacturers  Mutual  Standards.  —  The  follow- 
ing examples  of  approved  mill  construction  are  taken,  by  per- 
mission, from  "  Slow-burning  or  Mill  Construction,"  (revised 
edition  of  1908),  issued  by  the  Boston  Manufacturers  Mutual 
Fire  Insurance  Company,  31  Milk  St.,  Boston,  Mass.  Copies 
of  that  report  may  be  had  at  twenty-five  cents  each. 

Belt,  Stairway,  and  Elevator  Towers.  —  Fig.  9  illustrates 
a  standard  typical  arrangement  of  driving  belts,  stairway,  and 


BELT,   STAIRWAY  AND    ELEVATOR   TOWERS 


ENGINE   MOUSE 


BOIUER  HOUSE, 


MAIN         MILL. 


PICKER     MOUSE 


I  I 


FIG.  9.  —  Typical  Arrangement  of  Belts,  Stairway  and  Elevator. 


elevator,  boiler  house,  etc.     The  specific  points  of  interest  from 
the  standpoint  of  fire  protection  are: 

Main  belts  entirely  separated  from  the  manufacturing  rooms 
by  solid  brick  walls,  to  prevent  fire  being  communicated  from 
the  power  plant  to  the  mill,  or  from  one  floor  to  another.  Neglect 
of  this  precaution  has  resulted  in  many  serious  fires. 


SLOW-BURNING   OR   MILL   CONSTRUCTION  81 


82 


FIRE    PREVENTION    AND    FIRE    PROTECTION 


Elevator  and  stairs  in  brick  towers  with  standard  automatic 
fire  doors. 

No  holes  through  floors  through  which  fire  and  water  may 
readily  pass  from  floor  to  floor. 

Closets  in  a  separate  tower  rather  than  in  the  manufacturing 
rooms. 

Boiler  plant  cut  off  from  engine  room  by  brick  wall  with 
doorway,  also  protected  by  standard  automatic  sliding  fire  door. 
Boilers  under  manufacturing  rooms  are  undesirable  from  many 
standpoints  other  than  from  that  of  fire.  They  should  there- 
fore be  in  one-story  buildings  cut  off  by  fire  wall  from  the  rest 
of  the  plant. 

•  Modern  Slow-burning  Mill  Building.  —  A  typical  modern 
mill  building  is  shown  in  Fig.  10.  The  special  features  illus- 
trated comprise: 

1.  Walls.  —  Brick  walls  at  least  1  foot  thick  (16  inches  for 
best  work)  in  top  story  and  increased  in  thickness  at  lower  floors 
to   support   additional   load.     The   pilastered   wall   has   many 
favorable   features   and  is   often  preferred   to   the   plain   wall. 
Window  and  door  arches  should  be  of  brick,  window  and  outside 
door  sills  and  underpinning  of  granite  or  concrete. 

2.  Roofs.  —  Roofs  of  3-inch  pine  plank,  spiked  directly  to 
the  heavy  roof  timbers  and  covered  with  5-ply  tar  and  gravel 

roofing.  Roofs  should  pitch  J  inch 
to  f  inch  per  foot.  An  incombus- 
tible cornice  is  recommended  when 
there  is  exposure  from  neighboring 
buildings.  Fig.  11  gives  detail  of 
a  roof  timber  resting  on  a  cast-iron 
wall  plate,  with  anchor  bolt,  and 
over-hanging,  open  wood  cornice. 
3.  Floors.  —  Floors  of  spruce 
plank  4  inches  or  more  in  thickness 
according  to  the  floor  loads,  spiked 
directly  to  the  floor  timbers  and 
kept  at  least  ^-inch  clear  of  the 
face  of  the  brick  walls.  In  floors 
and  roof,  the  bays  should  be  8  to 
10i  feet  wide  and  all  plank  two  bays  in  length,  laid  to  break 
joints  every  4  feet  and  grooved  for  hard- wood  splines.  Usually 
a  top  floor  of  birch  or  maple  is  laid  at  right  angles  to  the  plank- 
ing, but  the  best  mills  have  a  double  top  floor,  the  lower  one  of 
soft  wood  laid  diagonally  upon  the  plank,  and  the  upper  one  laid 
lengthwise.  This  latter  method  allows  boards  in  alleys  to  be 
easily  replaced  when  worn,  and  the  diagonal  boards  brace  the 
floors,  reduce  vibration,  and  distribute  the  floor  load  even  better 
than  the  former  method. 

Between  the  planking  and  the  top  floor  should  be  two  or 
three  layers  of  heavy  tarred  paper,  laid  to  break  joints,  and  each 


Flashing 


Roofing,. 


Roof 
Anchor 


FIG.  11.  —  Detail  of  Roof  Timber 
on  Wall  Plate. 


SLOW-BURNING    OR   MILL    CONSTRUCTION 


83 


mopped  with  hot  tar  or  similar  material  to  produce  a  reasonably 
water-tight  as  well  as  dust-tight  floor. 

Rapid  decay  of  basement  or  lower'  floors  of  mills  makes  it 
desirable,  whenever  wood  is  not  absolutely  necessary,  to  provide 
cement  floors  for  these  places.  If  wooden  floors  are  required, 
crushed  stone,  cinders,  or  furnace  slag  should  be  spread  evenly 
over  the  surface  and  covered  with  a  thick  layer  of  hot  tar  con- 
crete, on  which  is  often  laid  tarred  felt,  well  mopped  with  hot 
tar  or  asphalt,  on  which  a  floor  of  2-inch  or  3-inch  impregnated 
plank  should  be  pressed,  nailed  on  edge  without  perforating  the 
waterproofing  under  it,  and  the  hard-wood  top  floor  boards  nailed 
across  the  plank.  Cement  concretes  promote  decay  of  wood  in 
contact  with  them.  If  extra  support  is  required  for  heavy 
machinery,  independent  foundations  of  masonry  should  be 
provided. 

4.  Timbers  and  Columns.  —  All  woodwork  in  standard  con- 
struction, in  order  to  be  slow-burning,  must  be  in  large  masses 
that  present  the  least  possible  surface  to 
a  fire.  No  sticks  less  than  6  inches  in 
width  should  be  used,  even  for  the  light- 
est roofs,  and  for  substantial  roofs  and 
floors  much  wider  ones  are  needed.  Tim- 
bers should  be  of  sound  Georgia  pine, 
and  for  sizes  up  to  14  by  16  inches,  single 
sticks  are  preferred,  but  timbers  7  or  8 
inches  by  16  are  often  used  in  pairs, 
bolted  together  without  air  space  between. 
They  should  not  be  painted,  varnished,1 
or  filled  for  three  years  because  of  danger 
of  dry  rot,  and  an  air  space  should  be 
left  in^the  masonry  around  the  ends  for 
the  same  reason.  Timbers  should  rest  on 
cast-iron  plates  or  beam  boxes  in  the 
walls  and  on  cast-iron  caps  on  the  col- 
umns. Fig.  12  shows  a  wood  beam  rest- 


FIG.  12.  —  Detail  of  Floor 
Girder  on  Wall  Plate. 


rJWhere  wall  offsets,  omit  bar 
in.  x  2  in.  Wrought. Iran  Bar 

.  longer  than  width 
of  beam. 


on  a  cast-iron  wall 
plate,  with  lug  cast  on 
plate  to  anchor  the  beam, 
and  flange  on  end  of  plate 
to  anchor  to  wall. 

Beam  boxes  as  illus- 
trated in  Fig.  13  are  of 
value,  as  they  strengthen 
the  walls  when  floor  loads 
are  heavy  and  distance 
between  windows  small; 
they  facilitate  the  laying 
of  the  brick  and  handling 
of  the  beams,  and  there 
is  less  possibility  of  breaking  away  the  brick  in  putting  the  beams 
in  place.  They  also  insure  a  proper  air  space  around  beams. 


FIG.  13.  —  Detail  of  Cast-iron  Wall 
for  Floor  Timbers. 


Box 


84 


FIRE    PREVENTION    AND    FIRE    PROTECTION 


Columns  of  southern  pine  should  be  bored  through  the  cen^ 
ter  by  a  IJ-inch  hole,  with  |-inch  vent  holes  top  and  bottom, 
and  ends  should  be  carefully  squared. 
They  also  should  not  be  painted  until 
thoroughly  seasoned,  to  prevent  dry 
rot.  Columns  should  be  set  on  pin- 
tles, which  may  be  cast  in  one  piece 
with  the  cap,  or  separately,  as  pre- 
ferred. Fig.  14  shows  a  roof  timber 
resting  on  column  cap,  cast  to  fit  slope 
of  roof.  Timbers  are  tied  by  1-inch 
round  iron  dogs.  A  typical  column 
and  girder  connection  is  shown  in 
Fig.  15. 

Columns  of  cast  iron  are  preferred  by  some  engineers,  and 
when  the  building  is  equipped  with  automatic  sprinklers,  have 
proved  satisfactory,  but  are  not  as  fire-resisting  as  timber. 
Wrought-iron  or  steel  columns  should  not  be  used  unless  encased 
with  at  least  2  inches  of  fireproofing. 


Roof 
Timber 


FIG.  14. —  Detail  of  Roof  Tim- 
ber on  Column  Cap. 


Post 


Top  Flooring 
'Tarred  Paper 


FIG.  15.  —  Detail  of  Typical  Column  and  Girder  Connection. 

5.  Windows.  —  Windows  to  be  placed  as  high  and  made  as 
wide  as  possible  to  obtain  the  best  light,  and  the  use  of  ribbed 
glass  is  recommended  in  upper  sashes. 

Four-story  Storehouse.  —  Fig.  16  illustrates  the  best  prac- 
tice for  a  storehouse  more  than  two  stories  in  height,  intended 
for  the  storage  of  raw  stock  or  goods.  The  important  features 
of  design,  which  should  be  especially  kept  in  mind  when  applying 
to  special  cases,  are  as  follows: 

Construction.  —  The  area  of  each  compartment  to  be  pref- 
erably 5000  square  feet  but  not  over  10,000  square  feet  for  non- 
hazardous  storage;  5000  square  feet  is  the  usual  standard  for 
cotton.  The  height  of  each  story  for  cotton,  or  for  other  readily 
inflammable  material,  should  be  such  as  to  permit  i  the  storage 
of  but  one  bale  on  end  —  8  feet  from  floor  to  floor  is  generally 


SLOW-BURNING   OR   MILL   CONSTRUCTION  85 

sufficient.  When  designed  for  cased  goods  the  height  should 
be  sufficient  to  take  two  cases,  with  10  inches  to  12  inches  under 
the  beams,  in  order  not  to  impede  the  distribution  of  water  from 
the  sprinklers.  Ample  provision  for  passageways  should  also 
be  made. 

The  compartments  should  be  separated  from  each  other  by 
solid  brick  walls  and  be  accessible  only  from  the  elevator  and 
stair  tower,  with  the  openings  here  protected  by  standard  auto- 
matic sliding  fire  doors.  This  will  confine  damage  to  the  com- 
partment in  which  a  fire  may  start. 

Walls.  —  To  be  same  as  for  mill  building  previously  de- 
scribed. 

Roofs.  —  Generally  same  as  for  mill  building.  Conductor 
pipes  should  not  pass  through  the  building  unless  the  storehouse 
is  to  be  heated  in  winter.  The  fire  wall  should  be  carried  2£  feet 
above  the  roof,  and  provided  with  vitrified  coping  laid  in  Portland 
cement  mortar. 

Floors.  —  Floors  on  each  story  in  the  tower  should  be  about 
one  inch  lower  than  the  floors  in  the  adjoining  compartment. 
The  sills  should  be  sloped  to  make  up  for  this  difference  in  level. 
The  sill  of  the  outside  door  in  the  tower  should  also  be  lower  than 
the  tower  floor. 

Water  on  floors  in  the  tower  will  ordinarily  flow  down  the 
stair  and  elevator  shaft,  and  arrangement  of  floor  levels  indicated 
above  will  ordinarily  prevent  water  coming  from  an  upper  floor 
from  flowing  into  one  of  the  lower  compartments,  if  it  is  escaping 
through  the  tower.  Cast-iron  scuppers  are  advised  and  should 
be  set  in  the  brickwork  at  frequent  intervals,  so  designed  that 
they  will  carry  away  rapidly  a  maximum  quantity  of  water  from 
the  floors  of  each  compartment  (see  Chapter  XI).  Water-tight 
floors  are  always  desirable  and  become  a  necessity  in  certain 
storehouses  with-valuable  contents,  but  in  three-  and  four-story 
storehouses  are  not  usually  considered  essential.  In  higher 
buildings  one  or  two  floors  are  often  covered  with  an  inch  of 
rock  asphalt,  properly  applied  and  turned  up  around  posts  and 
at  walls  about  4  inches.  Considerable  care  is  necessary  in  con- 
structing a  water-tight  floor  if  satisfactory  results  are  to  be 
obtained.  All  water  will  then  pass  out  at  the  scuppers  and  no 
damage  is  caused -on  floors  below.  There  must  be  no  vertical 
openings  through  floors  except  in  the  tower.  Fire  thus  cannot 
gain  access  from  one  floor  to  another  without  burning  through 
the  solid  plank  floor. 

Floors  should  be  of  spruce  plank  3  inches  or  4  inches  or  more 
in  thickness  according  to  the  floor  load  and  should  be  spiked 
directly  to  the  floor  timbers.  In  floors  and  roof  the  bays  should 
be  from  8  to  10J  feet  wide  and  all  plank  two  bays  in  length  laid 
to  break  joints  every  4  feet  and  grooved  for  hard-wood  splines. 
The  plank  at  the  walls  should  be  left  out  until  the  windows  are 
put  in,  to  prevent  damage  from  swelling  in  case  of  rain. 

The  top  floor  should  be  of  maple  or  other  close-grained  hard 
wood.  The  floor  and  roof  timbers  should  be  of  sound  Georgia 


86 


FIRE   PREVENTION   AND   FIRE   PROTECTION 


FIRST  FLOOR  PLAN 


FRONT  ELEVATION 

FIG.  16.  — Typical  Four-story  Storehouse. 

pine  in  single  sticks,  if  possible,  but  if  necessary  to  use  double 
beams,  they  should  be  bolted  together  without  air  space  between. 
Timbers  should  rest  on  cast-iron  plates  or  beam  boxes  in  the 
walls  and  on  cast-iron  caps  in  the  columns.  At  least  a  half  an 
inch  air  space  should  be  left  around  all  beams  built  into"  the 
masonry.  Columns  of  Southern  pine  should  be  cut  with  their 
ends  square  with  the  axis. 

Windows  may  be  of  small  area,  but  should  be  placed  high 
in  order  to  give  the  best  light. 

Protection.  —  A  standard  equipment  of  automatic  sprinklers 
should  be  installed  throughout.  In  mild  climates,  and  even 
under  s^me  conditions  in  cold  ones,  it  is  advisable  to  install  a 
line  of  l|-inch  steam  pipe  overhead  on  each  floor  to  provide 
sufficient  heat  to  avoid  freezing  of  the  water  in  the  sprinkler 
pipes.  If  the  building  is  not  heated  an  air  system  with  water 
controlled  by  an  approved  dry-pipe  valve  must  be  used,  and  all 


SLOW-BURNING   OR  MILL   CONSTRUCTION  87 


$    CROSS  SECTION  THROUGH  TOWER 


FIG.  16.  —  Typical  Four-story  Storehouse  (continued). 

pipes  must  have  J-inch  pitch  per  10  feet  back  to  main  riser  to 
insure  proper  drainage.  A  dry-pipe  valve  chamber  may  be 
located  in  the  basement  of  the  stair  tower.  The  number  of 
sprinklers  on  one  dry-pipe  valve  should  preferably  not  exceed 
300,  and  400  is  the  maximum  allowed  under  the  rules.  By 
heating  the  storehouse  the  expense  of  installation  and  mainte- 
nance of  the  dry-pipe  system  is  avoided,  and  in  buildings  of  this 
substantial  character  only  a  very  small  amount  is  needed,  as 
it  is  only  necessary  to  keep  the  temperature  above  the  freezing 
point. 

Standpipes.  —  Standpipes  are  often  advisable  in  the  stair 
towers  of  the  higher  storehouses,  and  provision  should  be  made 
below  frost  for  draining  them  in  cold  weather,  with  a  readily 
accessible  indicator  post  gate  for  controlling  the  supply  in  case 
of  emergency. 

Water  supply  to  the  sprinklers  and  Standpipes,  as  well  as 


88 


FIRE   PREVENTION   AND   FIRE   PROTECTION 


for  such  outside  hydrants  as  may  be  needed,  should  be  of  good 
capacity  from  two  independent  sources,  such,  for  example,  as  is 
outlined  in  description  of  Fig.  4. 

One-story  Storehouse.  —  Standard  construction  for  one- 
story  compartment  storehouses,  intended  primarily  for  the 
storage  of  cotton  but  adapted  for  other  stock  in  bales  or  cases, 
is  shown  in  Fig.  17.  The  design  illustrates  the  following  special 
points  which  insure  the  lowest  possible  insurance  charges: 

Construction.  —  The  area  of  each  compartment  should  not 
be  over  10,000  square  feet  for  non-hazardous  storage,  nor  more 


FRONT  ELEVATION 


LONGITUDINAL  SECTION 


>*~ 

*•  is" 

\  •  , 

EACH  COMPARTMENT  50'»  KX)' 

* 

^s'V^" 

> 

.., 

- 

a 

FIG.  17.  —  Typical  One-story  Storehouse. 

than  5000  square  feet  for  cotton.  The  height  should  accom- 
modate one  bale  standing  on  end  with  good  clearance  space 
above,  to  provide  for  distribution  of  water  from  sprinklers  or  to 
allow  cased  goods  to  be  piled  two  high  without  coming  up  between 
the  beams,  should  it  be  desired  to  use  a  section  wholly  for  this 
purpose.  Nothing  should  ever  be  piled  between  the  beams  or 


SLOW-BURNING    OK    MILL    CONSTRUCTION 


89 


within  a  foot  of  the  under  side  of  them,  as  not  only  is  distribution 
of  water  impeded  but  the  sprinkler  pipes  are  liable  to  be  struck 
and  bent  or  broken  from  their  fastenings. 

Each  section  as  designed  has  a  capacity  of  600  bales  of  cotton 
on  end  or  corresponding  quantities  of  other  stock. 

The  compartments  are  separated  by  a  brick  fire  wall  12 
inches  thick  extending  not  less  than  2  feet  above  the  roof  and 
provided  with  a  vitrified  coping  laid  in  cement  mortar  at  the 
top.  There  should  be  no  doorways  in  these  division  walls. 

The  side  walls  are  of  brick  8  inches  thick  reinforced  by  12- 
inch  pilasters.  Solid  12-inch  walls  throughout  will  be  a  little 
more  substantial  and  not  much  more  expensive.  All  door 
openings  have  round-nosed  bricks  at  the  edges. 

The  floors  of  concrete,  pitched  slightly  to  the  doors,  are  laid 
some  distance  above  the  natural  surface  of  the  ground.  In  case 
the  ground  is  wet,  open  tiled  drains  should  be  laid  around  the 
edges  of  the  compartment  inside  the  foundation  and  tar  concrete 
used  for  the  floor  material. 

The  roofs  are  built  of  plank  and  timber  supported  on  sub- 
stantial posts  having  the  corners  rounded.  It  is  often  advisable 


Dogr 


18.  —  Detail  of  Roof  at  Division 
Wall. 


FIG.   19.  — Detail  of  Post  and  Roof 
Timbers. 


P"i< 

to  sheathe  these  posts  with  iron  about  3  feet  high  from  the  floor 
to  protect  them  from  trucks.  In  no  case  should  timber  less  than 
|  6  inches  in  thickness  be  used,  as  very  light  beams  are  readily 
combustible  and  even  a  slight  charring  takes  away  a  large  pro- 
portion of  .their  strength.  The  roof  covering  is  5-ply  felt  tar  and 
gravel  and  substantial  zinc  flashing  is  used  where  necessary. 
Fig.  18  shows  a  section  A-B,  illustrating  the  roof  at  the  division 
wall.  Fig.  19  shows  a  post  and  roof  timbers.  The  galvanized 


90  FIRE    PREVENTION   AND    FIRE   PROTECTION 

iron  ventilators  should  be  of  such  design  as  to  prevent  the  en- 
trance of  sparks  from  exposures. 

The  windows  are  placed  as  high  as  possible  and  have  wooden 
frames  glazed  with  common  glass.  The  sashes  are  hinged  at  the 
bottom  to  swing  inward  and  provided  with  chains  and  catch. 
Doors  and  windows  need  special  protection  if  there  are  exposures. 

Protection.  —  A  standard  equipment  of  automatic  sprinklers 
should  be  installed  in  each  section.  If  the  building  can  be 
slightly  heated  the  water  may  be  kept  on  the  sprinklers  through- 
out the  year,  but  if  there  is  danger  from  freezing,  an  air  system 
with  the  water  controlled  by  an  approved  dry-pipe  valve  must 
be  used.  All  pipes  must  have  at  least  J-inch  pitch  per  10  feet 
back  to  the  main  riser  to  insure  proper  drainage.  The  number 
of  heads  in  each  section  of  this  size  (50  by  100)  is  such  that  five 
compartments  may  be  controlled  by  one  dry-pipe  valve  located 
in  the  middle  section.  The  valve  room  is  built  low  in  the  ground 
with  double  walls,  roof,  window,  and  door,  to  prevent  entrance 
of  frost,  and  in  the  colder  climates  artificial  heat  such  as  steam 
or  an  electric  heater  is  advisable.  In  mild  climates  it  is  usually 
preferred  to  run  a  line  or  two  of  steam  pipe  overhead  in  each 
section  of  the  storehouse  for  use  in  the  few  cold  days,  and  thus 
avoid  the  expense  of  installation  and  maintenance  of  a  dry-pipe 
valve.  The  protection  by  this  method- is  much  superior. 

Water  supply  to  the  sprinklers  as  well  as  for  such  outside 
hydrants  as  may  be  needed  should  be  of  good  capacity  preferably 
from  two  independent  sources  such,  for  example,  as  outlined  for 
Fig.  4. 

One- story  Workshop.  —  For  workshops  on  cheap  level 
land,  especially  where  the  stock  is  heavy,  one-story  buildings 
have  proved  to  be  more  economical  in  cost  of  floor  area,  super- 
vision, moving  stock  in  process  of  manufacture;  and  machinery 
can  be  run  at  greater  speed  with  less  repairs  than  when  in  high 
buildings.  While  the  saw-tooth  form  of  roof  illustrated  in  a 
following  paragraph  is  applicable,  it  may  not  always  be  necessary 
or  advisable;  and  a  type  common  for  machine  shops,  foundries, 
and  similar  occupancy,  where  increased  head  room  is  required 
and  traveling  cranes  used  is  outlined  in  Fig.  20.  The  center 
section  over  the  crane  is  often  provided  with  saw-tooth  skylights 
with  excellent  results,  and  the  side  bays  and  others  made 
higher  for  a  gallery.  The>-;e  buildings  are  readily  warmed  and 
ventilated,  and  the  heavy  plank  roofs  are  free  from  condensation 
in  cold  weather.  Window  areas  should  be  as  large  as  practi- 
cable and  extend  as  high  as  possible.  Forced  circulation  of 
heated  air  is  very  desirable  in  connection  with  overhead  steam 
pipes. 


SLOW-BURNING    OR   MILL    CONSTRUCTION  91 


92  FIRE   PREVENTION    AND    FIRE    PROTECTION 

Roofs.  —  The  principles  of  standard  mill  construction  as 
given  for  modern  mill  building  should  be  followed.  Trusses  in 
roofs  are  ordinarily  from  8  to  20  feet  on  centers,  the  3-inch  plank 
spanning  the  distance  between  the  trusses  or  resting  on  purlins 
not  less  than  8  feet  on  centers  and  running  longitudinally.  It 
is  of  importance  that  monitors  be  of  substantial  plank  construc- 
tion with  wide  bays,  as  in  the  main  roofs. 

When  in  locations  exposed  by  other  buildings  of  hazardous 
construction  or  occupancy,  parapetted  brick  walls  and  cornices 
are  needed. 

Floors.  —  If  earth  or  cement  concrete  floors  are  not  suitable 
and  wood  floors  are  necessary,  they  may  be  made  up  of  broken 
slag  or  stone  several  inches  thick  and  thoroughly  rolled,  upon 
which  is  a  layer  of  4  inches  of  tar  concrete  and  on  this  one  inch 
of  asphalt  evenly  rolled.  On  this  2-inch  or  3-inch  hemlock  plank 
bedded  in  hot  pitch  are  laid  and  over  them  a  f-inch  or  l|-inch 
maple  floor  is  laid  at  right  angles  to  the  plank. 

Protection.  —  These  types  of  wide  bay  construction  are 
adapted  to  economical  installation  of  a  sprinkler  equipment  as 
the  minimum  number  of  heads  is  required,  thus  keeping  down 
the  cost. 

The  usual  outside  fire  protection  appliances  are,  of  course, 
to  be  provided. 

Fire  Curtains.  —  For  fire-  or  heat-stops  under  long  roof  areas, 
see  Chapter  XXI. 

"Saw-tooth"  Roofs.  —  The  great  advantages  and  the  in- 
creasing use  of  saw-tooth  roof  construction,  and  the  lack  of 
familiarity  with  it  at  many  factories,  make  it  desirable  to  outline 
important  features. 

Two  typical  designs  are  illustrated;  Fig.  21,  a  textile  weave 
shed  with  good  basement  for  shafting  for  driving  looms,  on  main 
floor  above,  thus  dispensing  with  the  overhead  shafting  and 
belting  in  the  weave  room;  Fig.  22,  a  design  for  a  light  machine 
shop  or  foundry.  Other  designs  are  applicable  with  light  wooden 
trusses  or  reinforced  concrete. 

It  may  here  be  well  to  state  that  the  light  roof  of  2-inch  and 
3-inch  joists  and  boards  should  never  be  used  and  that,  while 
the  principles  of  slow-burning  or  mill  construction,  with  the 
heavy  timbers,  are  preferred,  the  increasing  difficulty  of  promptly 
obtaining  yellow-pine  lumber  of  good  dimensions,  and  its  in- 
creasing cost,  often  necessitate  the  use  of  trussed  forms,  using 
rather  light  timbers,  but  in  no  case  should  they  be  less  than 
six  inches  in  width  and  of  depth  sufficient  to  carry  the  load,  this 
in  order  that  they  may  be  " slow-burning."  The  roof  in  all  cases 
should  be  of  plank  with  wide  bays. 

The  adaptability  of  the  light  forms  of  steel  for  framing 
trusses,  especially  when  wide  spans  are  needed,  often  compels 
their  use,  and  in  plants  having  safe  occupancy,  such  as  metal 


SLOW-BURNING   OR   MILL   C6NSTRUCTION  93 


94  FIRE   PREVENTION   AND   FIRE   PROTECTION 

workers,  are  not  objectionable,  providing  adequate  sprinkler 
protection  with  good  water  supply  is  available  to  prevent  quick 
failure  of  the  steel  work,  due  to  heat  from  combustion  of  contents 
or  roof.  Similar  protection  is,  of  course,  needed  in  shops  with 
wooden  trusses  if  disastrous  fires  are  to  be  prevented,  but  ex- 
perience has  shown  that  the  steel-trussed  roof  will  fail  much 
quicker  than  would  one  of  wood  under  similar  conditions. 
Wooden  posts  are  nearly  always  available  and  should  be  given 

Preference,  but  if  light  steel  columns  are  necessary  they  should 
e  well  protected  by  insulating  materials,  if  in  rooms  containing 
combustibles,  as  the  column  is  the  vital  part  of  the  roof  support. 

The  advantages  and  disadvantages  of  saw-tooth  roofs  may 
be  outlined  as  follows: 

Advantages.  —  Uniform  diffusion  of  light  throughout  the 
room,  thus  making  all  space  in  it  available.  With  all  interior 
surfaces  painted  white  and  with  ribbed  glass  in  the  sash,  the 
diffusion  of  light  is  almost  perfect. 

Adaptability  for  lighting  large  floor  areas  in  wide  buildings 
with  low  head  room  compared  to  what  is  necessary  in  wide 
buildings  with  the  ordinary  form  of  monitor  skylights. 

They  provide  the  true  solution  to  the  problem  of  excluding 
the  direct  rays  of  the  sun  and  obtaining  the  very  desirable  north 
light. 

Economy  in  lighting,  in  that  they  lessen  the  fixed  charges 
due  to  the  lessened  number  of  hours  per  day  during  which  arti- 
ficial light  is  necessary. 

Better  working  conditions,  especially  in  textile  mills,  there- 
fore increasing  production  and  encouraging  permanency  of  the 
help. 

The  saw-tooth  form  is  especially  adapted  to  weaving  and 
similar  processes  in  textile  factories,  machine  shops,  foundries 
doing  light  work,  and  similar  work,  such  as  assembling  and 
drafting,  and  in  some  dye  houses  where  careful  matching  of 
colors  is  necessary. 

Disadvantages.  —  While  testimony  of  those  having  had  ex- 
perience with  saw-tooth  roofs  is  almost  uniformly  favorable, 
more  or  less  difficulties  have  been  experienced,  practically  all  of 
which  may  be  summed  up  as  due  either  to  faulty  design  or  poor 
workmanship.  The  difficulties  in  general  are  caused  by  leaks, 
due  to  severe  conditions  during  winter  in  our  northern  climates, 
poor  ventilation,  excessive  heat  when  roofs  are  thin,  or  excessive 
condensation  on  under  side  of  roof  and  glass  when  the  temperature 
outside  is  low  and  there  is  considerable  moisture  in  the  rooms. 

Suggestions.  —  The  following  suggestions  show  how  these 
difficulties  may  be  obviated  if  applied  to  special  cases  by  com- 
petent engineers  or  architects.  What  is  good  engineering  from 
the  view-point  of  the  manufacturer  can  also  be  good  fire  protec- 
tion engineering,  and  any  design  should  be  adapted  to  both  if 
the  best  interests  of  the  manufacturer  are  to  be  served. 

a.  It  being  desirable  to  avoid  direct  sunlight  and  at  the 
same  time  obtain  abundance  of  light  perfectly  diffused,  the  saw- 


SLOW-BURNING    OR   MILL    CONSTRUCTION 


95 


96  FIRE    PREVENTION    AND    FIRE    PROTECTION 

teeth  should  face  approximately  north  and  the  glass  should  be 
inclined  to  the  vertical  to  take  advantage  of  the  brighter  light 
in  the  upper  sky  and  to  prevent  cutting  off  the  light  by  the  saw- 
tooth immediately  in  front,  and  above  all  to  assure  the  diffusion 
of  the  light  upon  the  floor  rather  than  on  the  under  side  of  the 
roof  planking. 

b.  For  the  glass  an  angle  of  20  degrees  to  25  degrees  with 
the  vertical,  and  an  angle  of  approximately  90  degrees  at  the 
top  of  the  saw-tooth  will  be  about  right,  the  variations  to  depend 
on  the  amount  of  light  required  and  the  latitude.     A  sharper 
angle  at  the  top  is  not  needed,  as  it  increases  the  cost,  there  being 
more  roof  to  cover  and  larger  spans.     More  glass  is  also  required 
in  proportion  and  the  light  is  not  as  good,  more  sky  light  being 
lost  and  too  much  thrown  on  under  side  of  roof. 

c.  Double  glazing  with  space  between  is  preferred  on  account 
of  its  conducting  qualities,  but  is  not  always  necessary,  except 
in  the  north  country.     The  inside  glazing  should  be  factory 
ribbed  glass,  with  ribs  vertical  and  inside.     Shadows  cast  by 
trusses  are  then  almost  unnoticeable. 

d.  Condensation  gutters  are  needed  inside  at  the  bottom  of 
the  sash  and  they  should  be  drained  through  inside  conductors 
and  not  to  the  outside  under  bottom  of  the  sash,  as  these  latter 
admit  cold  air  and  are  liable  to  freeze. 

e.  Valleys  between  the  saw-teeth  should  be  flat,  14  inches 
to  2  feet  in  width  and  pitched  one-half  inch  per  foot  towards 
the  conductors,  which  should  be  of  ample  size,  and  not  much 
over  50  feet  apart,  and  preferably  less.     The  necessary  pitch 
may  be  obtained  by  cross  pieces  of  varying  heights  on  top  of 
the  trusses,  thus  avoiding  hollow  spaces. 

/.  Leaks,  a  common  fault,  may  ordinarily  be  prevented  by 
careful  design  of  gutters,  valleys,  and  sashes,  and  by  insisting 
on  good  workmanship  and  materials.  The  roof  covering  of 
asphalt  or  pitch  should  be  continuous  through  the  valleys  and 
extend  up  to  the  glass.  One  form  of  construction  understood 
to  have  been  very  satisfactory  is  illustrated  in  Fig.  23,  and  in 
connection  with  it  reference  should  be  made  to  the  papers  and 
discussion  on  "Saw-tooth  Roofs"  in  Transactions  A.  S.  M.  E., 
Vol.  XXVIII  (1907),  which  contain  much  of  value. 

g.  Experience  has  demonstrated  the  advantage  of  a  com- 
bination of  direct  radiation  with  a  fan  sufficient  only  for  ven- 
tilation and  tempering  the  room.  Heating  pipes  should  usually 
be  placed  overhead  and  directly  under  the  front  of  the  saw-teeth 
and  run  the  entire  length,  and  in  this  position  assist  in  prevent- 
ing condensation.  Where  there  is  no  moving  shafting,  some 
forced  circulation  is  necessary,  and  is  best  obtained  by  fan,  often 
driving  air  from  a  dry  basement  or  outside  as  required,  and  dis- 
charging it  over  heating  coils  to  the  floor  above.  In  weave  and 
similar  rooms  is  this  especially  necessary  and  advantageous  in 
promoting  health  and  comfort  of  employees,  making  greater 
efficiency  possible.  Ventilation  and  cooling  of  these  large  areas 
with  comparatively  low  stories  must  not  be  neglected.  Ample 


SLOW-BURNING    OR   MILL    CONSTRUCTION 


97 


vents  are  needed  at  top  in  the  shape  of  large  metal  ventilators 
with  double  walls  and  tight  dampers.  They  are  recommended 
instead  of  pivoted  or  swinging  sash,  which  are  apt  to  leak  in 
driving  storms,  and  when  open  allow  dirt  to  blow  in  off  the  roof. 
Good  windows  are  advised  in  side  walls  and  experience  has 
shown  their  value. 

h.  Framing  of  the  saw-teeth  may  be  in  the  timber,  steel,  or 
reinforced  concrete.  The  design  should  be  such  as  to  obstruct 
the  light  as  little  as  possible  and  strong  enough  to  hold  wet  snow 


Galv.  Iron  Flashing 

Ply  Roofing:  plus  extra  layer  of  Felt 
Galv.  Iron 


FIG.  23.  —  Detail  of  Valley  of  "Saw-tooth"  Roof. 

without  sagging,  and  stiff  enough  to  carry  shafting  motors,  etc., 
when  they  are  to  be  overhead.  When  wood  or  steel  is  used  the 
roof  planking  should  be  3  inches  or  over,  spanning  wide  bays 
of  8  to  10  feet. 

Hollow  spaces Jn  roofs  should  not  be  permitted.  They  are 
very  undesirable  from  a  fire  standpoint,  and  any  condensation 
which  may  take  place  in  them  during  cold  weather  soon  rots 
both  plank  and  sheathing. 

Sheathing,  even  without  spaces  behind  it,  is  more  or  less  a 
bad  feature,  as  it  is  readily  combustible,  but  if  used  should  be 
applied  directly  to  the  under  side  of  the  roof  plank,  with  only  a 
layer  of  some  insulating  material  between,  so  that  there  may  be 
no  concealed  space.  If  three-inch  plank  is  sufficient  for  a  flat 
roof  it  should  be  for  a  saw-tooth,  and  with  good  circulation  of 
air  there  should  be  no  trouble  except  in  wet  rooms,  where  con- 
densation is  bound  to  occur,  whether  under  a  roof  or  the  floor  of 
the  room  above,  unless  large  quantities  of  dry  air  are  discharged 
into  the  room. 


98  FIRE    PREVENTION    AND   FIRE    PROTECTION 

Saw-tooth  roofs  necessarily  cost  more,  as  there  is  practically 
the  same  amount  of  roofing  as  in  flat  roofs,  and  in  addition  there 
is  the  cost  of  windows,  glazing,  flashing,  conductors,  condensa- 
tion gutters  for  the  skylights,  and  a  somewhat  larger  cost  of 
heating.  The  additional  cost  of  these  items  does  not,  however, 
fairly  represent  comparative  cost,  as  there  should  be  considered 
the  total  cost  of  the  building  compared  with  ordinary  one  of 
sufficiently  high  stories  and  narrow  enough  to  give  the  required 
light.  When  this  is  done  the  slight  additional  cost  is  far  out- 
weighed by  advantages  of  the  type  for  work  where  good  light  is 
desirable. 

Requirements  of  National  Board  of  Fire  Underwriters.  - 

The  foregoing  descriptions  of  mill  constructed  buildings  consti- 
tute the  practice  recommended  by  the  Boston  Manufacturers 
Mutual  Fire  Insurance  Company  after  years  of  experience  in 
this  class  of  risks.  Similar  specifications  of  design  and  con- 
struction, only  much  more  limited  in  scope,  are  promulgated 
by  the  National  Board  of  Fire  Underwriters  in  the  leaflet  "  Uni- 
form Requirements,"  copies  of  which  may  be  had  by  addressing 
the  National  Board,  135  William  St.,  New  York  City,  or  the 
National  Fire  Protection  Association,  87  Milk  St.,  Boston. 

The  latter  requirements,  however,  are  made  principally  from 
the  standpoint  of  underwriters,  and  are  in  no  way  intended  as  a 
guide  to  architects  or  mill  engineers  with  reference  to  strength. 

Questions  of  pure  construction,  strength,  etc.,  in  mill  build- 
ings should  be  governed  by  recognized  principles  of  good 
practice,  even  though  local  building  laws  or  underwriters'  re- 
quirements permit  less. 

Dry  Rot  in  Timbers.  —  In  describing  the  construction  of  a 
modern  slow-burning  mill  building,  attention  has  been  called 
to  the  necessity  of  boring  l|-inch  holes  through  the  centers  of 
wood  columns,  also  to  the  fact  that  such  columns  should  not 
be  painted  until  thoroughly  seasoned.  This  is  to  prevent  dry 
rot  in  the  timbers  —  a  decay  or  disease  which  may  cause  serious 
failure,  as  is  proven  by  the  sudden  collapse  of  a  factory  building 
in  New  York  City,  after  a  fire  in  the  building  in  question  was 
well  under  control  by  the  fire  department.  An  examination  made 
by  Prof.  Ira  H.  Woolson  demonstrated  the  fact  that  the  collapse 
resulted  from  dry  rot  which  had  seriously  weakened  the  wooden 
columns. 

Dry  rot  is  a  well-known  fungous  disease  of  wood,  which  is 
sure  to  develop  when  green  or  wet  timber  is  encased,  so  that  air 


SLOW-BURNING    OR   MILL   CONSTRUCTION  99 

may  not  circulate  around  it.  Most  building  specifications 
require  that  the  ends  of  wooden  beams  encased  in  walls  shall 
have  an  air  space  around  them  to  prevent  dry  rot.  The  rules 
of  the  Factory  Mutual  Insurance  Companies  of  Boston  specify 
that  wooden  posts  shall  have  a  one  and  one-half-inch  hole  bored 
through  them,  and  two  one-half-inch  holes  crosswise  near  the 
top  and  bottom  to  prevent  checking.  No  mention  is  made  of 
this  provision  being  a  preventive  of  dry  rot,  but  it  is  quite  certain 
that  if  the  posts  in  this  building  had  been  thus  bored  they  would 
not  have  rotted.  The  timber  was  doubtless  only  partially 
seasoned,  and  the  placing  of  the  four-inch  socket  caps  upon  it 
effectually  excluded  the  air  from  the  ends,  giving  the  moisture 
no  chance  to  escape.  As  a  result  dry  rot  developed,  and  has  been 
slowly  progressing  until  practically  the  whole  cross-section  of 
the  posts  had  been  reduced  to  a  dry  punk,  which  could  be  broken 
by  the  fingers,  and  would  ignite  from  a  match.  The  worst  feature 
of  this  kind  of  decay  lies  in  the  fact  that  it  proceeds  from  the 
interior,  the  outside  seasoned  shell  of  the  timber  giving  no  indi- 
cation of  the  rottenness  within.  It  is  possible  that  the  manu- 
facture of  paper  in  the  building  may  have  produced  a  moist 
atmosphere  which  aided  the  decay  after  it  had  once  begun. 
Another  interesting  point  in  connection  with  the  matter  is  that 
this  condition  has  been  brought  about  in  a  period  of  eighteen 
years.  It  was  about  twenty-five  years  ago  that  the  late  Edward 
Atkinson  began  to  advocate  the  merits  of  slow-burning  mill  con- 
struction in  which  heavy  timber  framing  of  this  character  was 
employed.  A  large  number  of  factories  and  warehouses  have 
been  erected  since  that  time  of  similar  construction.  It  is  im- 
portant to  know  how  many  of  them  are  getting  into  a  dangerous 
condition  by  this  slow  method  of  deterioration.  If  the  posts  of 
such  buildings  have  been  bored  as  described  above,  they  are 
probably  in  as  perfect  condition  today  as  when  installed,  but 
unfortunately  all  building  specifications  have  not  made  boring 
of  posts  a  requisite,  and  where  buildings  were  erected  as  this 
one  was,  not  conforming  to  slow-burning  construction,  it  is  very 
likely  this  provision  of  post  protection  was  seldom  employed. 
The  soundness  of  posts  in  such  buildings  today  will  depend  upon 
their  degree  of  dryness  when  installed,  the  snugness  with  which 
the  caps  fitted,  as  well  as  the  atmospheric  conditions  of  the  build- 
ing, whether  dry  or  damp,  and  other  things  such  as  painting,  etc. 
It  is  well  known  that  painting  of  timber  before  it  is  thoroughly 
seasoned  is  conducive  to  dry  rot. 

Fortunately  the  condition  of  such  posts  can  easily  be  ascer- 
tained by  boring  a  half-inch  hole  through  them. 

While  yellow  pine  will  yield  to  dry  rot  under  favorable  sur- 
roundings, still  it  is  not  so  susceptible  to  the  disease  as  oak,  and 
it  is  known  that  certain  rot  fungi  will  attack  hardwoods,  and  not 
attack  resinous  woods  like  pine.  It  may  be  that  the  yellow-pine 
timber  in  this  building  was  less  affected  by  the  rot  than  the  oak 
because  the  particular  fungus  which  caused  the  trouble  would 
not  thrive  in  pine,  or  it  may  have  been  much  better  seasoned  than 


100         FIRE   PREVENTION   AND   FIRE   PROTECTION 

the  oak.  At  least  it  is  encouraging  that  the  yellow  pine  appar- 
ently resisted  the  disease  best,  for  the  day  of  oak  construction  is 
nearly  gone,  and  the  larger  proportion  of  such  constructions  in 
the  past  twenty  years  has  probably  been  of  pine.* 

See,  also,  paragraph  "Mill  Construction,"  Chapter  XXV, 
page 

Approximate  Cost  of  Mill  Buildings.  —  The  following 
paper,  presented  before  the  New  England  Cotton  Manufac- 
turers' Association,  April,  1904,  by  Mr.  Charles  T.  Main,  M.  Am. 
Soc.  M.  E.,  Mill  Engineer  and  Architect,  Boston,  is  used  by 
permission.  The  data  has  been  revised  by  Mr.  Main  to 
conform  to  prices  of  materials  and  labor  prevailing  about 
January,  1910. 

^  ****** 

"  It  is  sometimes  convenient  to  be  able  to  tell  off-hand  the 
approximate  cost  of  proposed  buildings,  or  the  cost  if  new,  of 
existing  buildings,  without  going  through  an  estimate  of  all  the 
quantities  of  materials  and  labor.  It  is  not  an  uncommon  thing 
to  hear  the  cost  of  mill  buildings  placed  from  70  cents  to  $1  per 
square  foot  of  floor  space,  regardless  of  the  size  or  number  of 
stories.  There  is,  however,  a  wide  range  of  cost  per  square  foot 
of  floor  space,  depending  upon  the  width,  length,  height  of  stories 
and  number  of  stories. 

Some  time  ago,  I  placed  a  valuation  upon  a  portion  of  the 
property  of  a  corporation,  including  some  400  or  500  buildings. 
In  order  to  have  a  standard  of  cost  from  which  to  start  in  each 
case,  I  prepared  a  series  of  diagrams  showing  the  approximate 
costs  of  buildings  varying  in  length  and  width  and  from  one 
story  to  six  stories  in  height.  The  height  of  stories  also  was 
varied  for  different  widths,  being  assumed  13  feet  high  if  25  feet 
wide,  14  feet  if  50  feet  wide,  15  feet  for  75  feet,  16  feet  for  100  feet 
and  over. 

The  costs  used  in  making  up  the  diagrams  are  based  largely 
upon  the  actual  cost  of  work  done  under  average  conditions  of 
cost  of  materials  and  labor  and  with  average  soil  for  foundations. 
The  costs  given  include  plumbing,  but  no  heating,  sprinklers, 
or  lighting.  These  three  latter  items  would  add  roughly  10  cents 
per  square  foot  of  floor  area. 

*  See  "Dry  Rot  in  Timbers,"  by  Prof.  Ira  H.  Woolson,  formerly  Adjunct 
Professor  of  Civil  Engineering,  Columbia  University.  Engineering  News, 
December  2,  1909. 


SLOW-BURNING    OR    MILL    CON.STI  I 'CTICN  101 

Use  of  Diagrams.  —  The  accompanying  diagrams,  (Figs.  24, 
25,  26,  27,  28,  and  29),  can  be  used  to  determine  the  probable 
approximate  cost  of  proposed  brick  buildings,  of  the  type  known 
as  "  slow-burning "  to  be  used  for  manufacturing  purposes,  with 
a  total  floor  load  of  about  75  pounds  per  square  foot,  and  these 
can  be  taken  from  the  diagrams  readily.  The  curves  were  de- 
rived primarily  to  show  the  estimated  cost  per  square  foot  of 
gross  floor  area  of  brick  buildings  for  textile  mills,  and  to  include 
ordinary  foundations  and  plumbing.  For  example,  if  it  is  de- 
sired to  know  the  probable  cost  of  a  mill  400  feet  long  by  100  feet 
wide,  three  stories  high,  refer  to  the  curves  showing  the  cost  of 
three-story  buildings.  On  the  curve  for  buildings  100  feet  wide, 
find  the  point  where  the  vertical  line  of  400  feet  in  length  cuts 
the  curve,  then  move  horizontally  along  this  line  to  the  left- 
hand  vertical  line,  on  which  will  be  found  the  cost  of  81  cents. 

The  cost  given. is  for  brick  manufacturing  buildings  under 
average  conditions  and  can  be  modified  if  necessary  for  the 
following  conditions: 

(a)  If  the  soil  is  poor  or  the  conditions  of  the  site  are  such  as 
to  require  more  than  the  ordinary  amount  of  foundations,  the 
cost  will  be  increased. 

(6)  If  the  end  or  a  side  of  the  building  is  formed  by  another 
building,  the  cost  of  one  or  the  other  will  be  reduced  slightly. 

(c)  If  the  building  is  to  be  used  for  ordinary  storage  purposes 
with  low  stories  and  no  top  floors,  the  cost  will  be  decreased 
from  about  10  per  cent,  for  large  low  buildings,  to  25  per  cent,  for 
small  high  ones,  about  20  per  cent,  usually  being  a  fair  allowance. 

(d)  If  the  buildings  are  to  be  used  for  manufacturing  purposes 
and  are  to  be  substantially  built  of  wood,  the  cost  will  be  de- 
creased from  about  6  per  cent,  for  large  one-story  buildings  to 
33  per  cent,  for  high  small  buildings;   15  per  cent,  would  usually 
be  a  fair  allowance. 

(e)  If  the  buildings  are  to  be  used  for  storage  with  low  stories 
and  built  substantially  of  wood,  the  cost  will  be  decreased  from 
13  per  cent,  for  large  one-story  buildings  to  50  per  cent,  for  small 
high  buildings;  30  per  cent,  would  usually  be  a  fair  allowance. 

(/)  If  the  total  floor  loads  are  more  than  75  pounds  per  square 
foot  the  cost  is  increased. 

(g)  For  office  buildings,  the  cost  must  be  increased  to  cover 
architectural  features  on  the  outside  and  interior  finish. 

The  cost  of  very  light  wooden  structures  is  much  less  than 


°'r°0      50    100    150    200    250    300  350  400    450  500 

Length  in  ft. 
FIG.  24. —  Size-cost  Diagram  for  Brick  Mill  Buildings:  One-story. 


*'°0 50     100    lf,0    200    250    300    350    400   4 50   500 

Length  in  ft. 
FIG.   25.  —  Size-cost  Diagram  for  Brick  Mill  Buildings:    Two-story. 

(102) 


^H|P 

I         Hi:] 

:::|:::::::::::::::::::: 

8            :::  5:*i:::::::::::::: 

:  :  :  Width. 
">-..  in  ft. 

j:||||!l!||!iil|||^ 

::±::±::::±s::::::: 

^*'U0      50     100    150    200    250  300    350   400   450   500 
Length  in  ft. 

FIG.  26.  —  Size-cost  Diagram  for  Brick  Mill  Buildings:   Three-story. 

2.105 
2.00 
1.90 
1.80 
col.70 


ui  1 1 1 1 1 1  i  i  1 1 1  1 1  1 1 1  i  i  1 1 1  i  i  i  1 1  *  i  1 1 1  i  i  i 1 1  i  i  1 1 

0      50    .100   150    200    250   300    350    400   450  500 
Length  in  ft. 

FIG.  27.  —  Size-cost  Diagram  for  Brick  Mill  Building:    Four-story. 


0'T00      oO     100    150    200    250    300   350  400    450   wv 

Length  in.  ft. 
FIG.  28.  —  Size-cost  Diagram  for  Brick  Mill  Buildings:    Five-story. 


20 1      )0   :OC     350   400    450  500 


Length  in  ft. 

FIG.  29.  —  Size-cost  Diagram  for  Brick  Mill  Buildings:    Six-story. 
(104) 


SLOW-BURNING    OR    MILL    CONSTRUCTION 

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106 


FIRE    PREVENTION    AND    FIRE    PROTECTION 


the  above  figures  would  give.  Table  I  shows  the  approximate 
ratio  of  the  costs  of  different  kinds  of  buildings  to  the  cost  of 
those  shown  by  the  curves. 

Evaluations.  —  The  diagrams  can  be  used  as  a  basis  of  valua- 
tion of  different  buildings. 

A  building,  no  matter  how  built  nor  how  expensive  it  was  to 
build,  cannot  be  of  any  more  value  for  the  purpose  to  which  it 
is  put  than  a  modern  building  properly  designed  for  that  par- 
ticular purpose.  The  cost  of  such  a  modern  building  is  then 
the  limit  of  value  of  existing  buildings.  Existing  buildings  are 
usually  of  less  value  than  new  modern  buildings  for  the  reason 
that  there  has  been  some  depreciation  due  to  age  and  that  the 
buildings  are  not  as  well  suited  to  the  business  as  a  modern 
building  would  be. 

Starting  with  the  diagrams  as  a  base,  the  value  can  be  approxi- 
mately determined  by  making  the  proper  deductions. 

The  diagrams  can  be  used  as  a  basis  for  insurance  valuations 
after  deducting  about  5  per  cent,  for  large  buildings  to  15  per 
cent,  for  small  ones,  for  the  cost  of  foundations,  as  it  is  not  cus- 
tomary to  include  the  foundations  in  the  insurable  value. 

Cost  Data. 

TABLE  II. —  DATA  FOR  ESTIMATING  COST  OF  BUILDINGS. 


Foundations 
including  exca- 
vations. 
Cost  per  lineal 
foot. 

Brick  walls. 
Cost  per  square 
foot  of  surface. 

Columns 
including 
piers  and 
castings. 

For  out- 
side 
walls. 

For  in- 
side 
walls. 

Outside 
walls. 

Inside 
walls. 

Cost  of  on  e. 

One-story  building 

$2.00 
2.90 
3.80 
4.70 
5.60 
6.50 

$1.75 
2.25 
2.80 
3.40 
3.90 
4.50 

$.40 
.44 
.47 
.50 
.53 
.57 

$.40 
.40 
.40 
.43 
.45 
.47 

$15.00 
15.00 
15.00 
15.00 
15.00 
15.00 

Two-story  building      .    . 

Three-story  building.  .  .  . 
Four-story  building 

Five-story  building  

Six-story  building  

Table  II  shows  the  costs  which  form  the  basis  of  the  estimates, 
and  these  unit  prices  can  be  used  to  compute  the  cost  of  any 
building  not  covered*  by  the  diagrams.  The  cost  of  brick  walls 


SLOW-BURNING    OR    MILL    CONSTRUCTION  107 

is  based  on  22  bricks  per  cubic  foot,  costing  $18  per  thousand 
laid.  Openings  are  estimated  at  40  cents  per  square  foot,  in- 
cluding windows,  doors,  and  sills. 

Ordinary  mill  floors,  including  timbers,  planking,  and  top  floor 
with  Southern  pine  timber  at  $40  per  thousand  feet,  B.  M.,  and 
spruce  planking  at  $30  per  thousand,  cost  about  32  cents  per 
square  foot,  which  has  been  used  as  a  unit  price.  Ordinary  mill 
roofs  covered  with  tar  and  gravel,  with  lumber  at  the  above 
prices,  cost  about  25  cents  per  square  foot  and  this  has  been  used 
in  the  estimates.  Add  for  stairways,  elevator  wells,  plumbing, 
partitions,  and  special  work. 

Assumed  Height  of  Stories.  —  From  ground  to  first  floor, 
3  feet.  Buildings  25  feet  wide,  stories  13  feet  high.  Buildings 
50  feet  wide,  stories  14  feet  high.  Buildings  75  feet  wide,  stories 
15  feet  high.  Buildings  100  feet  wide,  stories  16  feet  high.  Build- 
ings 125  feet  wide,  stories  16  feet  high. 

Deductions  from  Diagrams.  —  (1)  An  examination  of  the 
diagrams  shows  immediately  the  decrease  in  cost  as  the  width 
is  increased.  This  is  due  to  the  fact  that  the  cost  of  the  walls 
and  outside  foundations,  which  is  an  important  item  of  cost, 
relative  to  the  total  cost,  is  decreased  as  the  width  increases. 

For  example,  supposing  a  three-story  building  is  desired  with 
30,000  square  feet  on  each  floor: 

If  the  building  were  600  feet  by  50  feet,  its  cost  would  be  about 
99  cents  per  square  foot. 

If  the  building  were  400  feet  by  75  feet,  its  cost  would  be  about 
87  cents  per  square  foot. 

If  the  building  were  300  feet  by  100  feet,  its  cost  would  be  about 
83  cents  per  square  foot. 

If  the  building  were  240  feet  by  125  feet,  its  cost  would  be 
about  80  cents  per  square  foot. 

(2)  The  diagrams  show  that  the  minimum  cost  per  square 
foot  is  reached  with  a  four-story  building.  A  three-story  build- 
ing costs  a  trifle  more  than  a  four-story.  A  one-story  building 
is  the  most  expensive.  This  is  due  to  a  combination  of  several 
features : 

(a)  The  cost  of  ordinary  foundations  does  not  increase  in 
proportion  to  the  number  of  stories,  and  therefore  their  cost  is 
less  per  square  foot  as  the  number  of  stories  is  increased,  at  least 
j  up  to  the  limit  of  the  diagram. 

(6)  The  roof  is  the  same  for  a  one-story  building  as  for  one  of 


108 


FIRE   PREVENTION   AND   FIRE   PROTECTION 


any  other  number  of  stories,  and  therefore  its  cost  relative  to  the 
total  cost  grows  less  as  the  number  of  stories  increases. 

(c)  The  cost  of  columns,  including  the  supporting  piers  and 
castings,  does  not  vary  much  per  story  as  the  stories  are  added. 

(d)  As  the  number  of  stories  increases,  the  cost  of  the  walls, 
owing  to  increased  thickness,  increases  in  a  greater  ratio  than  the 
number  of  stories,  and  this  item  is  the  one  which  in  the  four-story 
building  offsets  the  saving  in  foundations  and  roof. 

(3)  The  saving  by  the  use  of  frame  construction  for  walls 
instead  of  brick  is  not  as  great  as  many  persons  think.  The  only 
saving  is  in  somewhat  lighter  foundations  and  in  the  outside 
surfaces  of  the  building.  The  floor,  columns,  and  roof  must  be 
the  same  strength  and  construction  in  any  case. 

Alternate  Method  of  Estimating  Cost. 

TABLE  III.  —  DATA  FOR  APPROXIMATING  COST  OF  MILL 

BUILDINGS  OF  KNOWN  SIZE  BUT  WITHOUT  DEFINITE 

PLANS  MADE. 


Height  of  building. 

Foundations 
including  excavation. 
Cost  per  lineal  foot. 

Brick  walls, 
including  doors  and 
windows.    Cost  per 
square  foot  of  surface. 

Outside 
walls. 

Inside 
walls. 

Outside 
walls 

Inside 
walls. 

One  story  

$2.00 

2.90 
3.80 
4.70 
5.60 
6.50 

$1.75 
2.25 
2.80 
3.40 
3.90 
4.50 

$.40 

.44 
.47 
.50 
.53 
.57 

$.40 
.40 
.40 
.43 
.45 
.47 

Two  stories 

Three  stories 

Four  stories  

Five  stories 

Six  stories  .    . 

Floors.  —  Thirty-eight  cents  per  square  foot  of  gross  floor 
space.  This  price  will  include  column  piers,  columns,  castings, 
and  wrought-iron. 

Roof.  —  Thirty  cents  per  square  foot,  including  projection, 
say  18  inches,  including  columns,  etc. 

Stairways  and  Elevator  Towers.  —  Allow  two  stairways  and  one 
elevator  tower  in  buildings  over  two  stories  high  up  to  150  feet 
long.  Allow  two  stairways  and  two  elevator  towers  up  to  300 


SLOW-BURNING    OR   MILL    CONSTRUCTION  109 

feet  long.  Allow  three  stairways  and  three  elevator  towers  over 
300  feet  long. 

Brick  Walls.  —  Enclosing  stairs  and  elevators,  estimated  as 
inside  walls. 

Stairs.  —  $100  per  flight,  per  story. 

Plumbing.  —  Allow  two  fixtures  on  each  floor  up  to  5000 
square  feet  of  floor  space,  and  add  one  fixture  for  each  additional 
5000  square  feet  or  fraction  thereof.  Allow  $75  per  fixture. 

Incidentals.  —  Add  about  10  per  cent,  for  incidentals. 

From  the  above  data  the  approximate  cost  of  any  size  and 
shape  of  building  may  be  estimated  in  a  few  minutes." 


PART   II 

FIRE-TESTS  AND  MATERIALS 


CHAPTER  V. 
EXPERIMENTAL   TESTING   STATIONS. 

Manufacturers9  Tests.  —  During  the  early-development 
etage  of  fire-resisting  construction,  our  practical  knowledge  of 
the  value  of  so-called  fire-resisting  materials  was  confined  to 
such  fire  and  water  tests  as  were  afforded  by  the  burning  of 
actual  buildings  in  which  such  materials  had  been  employed,  or 
to  special  tests  which  generally  originated  with  the  manufacturer 
of  some  material  or  construction,  and  which  were  made  for  the 
purpose  of  exploiting  the  product  offered.  These  latter  tests 
were  principally  devoted  to  demonstrating  the  strength  of  the 
material  or  construction,  but  as  new  materials  and  new  forms 
were  introduced,  endurance  tests,  as  well  as  load  tests,  were 
resorted  to  as  the  most  satisfactory  means  of  advertisement. 
Unfortunately,  many  if  not  most  such  endurance  tests  were  not 
reliable.  Some  notable  exceptions  are  conspicuous,  and  much 
praise  is  due  many  progressive  manufacturers,  but  the  general 
doubt  regarding  private  tests  for  the  purpose  of  advertisement 
gradually  resulted,  both  in  the  United  States  and  elsewhere,  in 
the  establishment  of  governmental,  municipal,  or  other  ex- 
perimental testing  stations  of  recognized  thoroughness  and 
impartiality,  where  materials  and  constructions  could  be  syste- 
matically tested  under  uniform  conditions. 

Principal  Testing  Stations.  —  Permanent  plants  or  stations 
(of  recognized  importance),  for  the  testing  of  materials  or  con- 
structions by  fire  and  water  tests,  are  maintained,  in  this  country, 

by  the  United  States  Government  at  Forest  Park,  St.  Louis, 
Mo. 

under  the  direction  of  the  National  Board  of  Fire  Under- 
writers, at  Chicago,  III. 

by  the  inspection  department  of  the  Associated  Factory  Mu- 
tual Fire  Insurance  Companies,  at  Boston,  Mass. 

by  Mr.  J.  S.  Macgregor  (The  "  Columbia  Fire  Testing 
Station")  at  Columbia  University,  New  York,  —  formerly  con- 
ducted by  Prof.  Ira  H.  Woolson. 


k 


114         FIRE   PREVENTION    AND   FIRE    PROTECTION 

In  Great  Britain,  the  British  Fire  Prevention  Committee, 
through  its  testing  station  in  London,  has,  at  least  heretofore, 
been  preeminent  in  the  matter  of  fire  and  water  tests,  while  in 
Europe,  tests  under  municipal  or  scientific  auspices  in  Munich, 
Berlin  and  Hamburg  have  been  of  interest. 

Official  tests  concerning  the  strength  of  materials  are  made  at 
the  United  States  Government  Arsenal,  at  Watertown,  Mass., 
and  at  the  University  of  Illinois. 

British  Fire  Prevention  Committee.  —  This  organization 
had  its  inception  immediately  after  the  disastrous  Cripplegate 
fire  in  London  in  1897.  It  was  incorporated  February,  1899. 
Systematic  tests  of  materials  and  constructions  were  commenced 
in  1899,  since  which  more  than  one  hundred  and  fifty  "Red 
Books"  or  reports  have  been  issued,  covering  a  wide  range  of 
actual  tests,  besides  valuable  papers  on  many  phases  of  fire 
prevention  and  fire  protection.  The  membership  represents 
government  departments  and  employees,  scientific  societies, 
architects,  engineers,  officers  of  fire  brigades,  etc.  The  objects 
of  the  committee  are  printed  on  the  first  page  of  all  its  "Red 
Books,"  as  follows: 

To  direct  attention  to  the  urgent  need  for  increased  pro- 
tection of  life  and  property  from  fire  by  the  adoption  of  preventive 
measures. 

To  use  its  influence  in  every  direction  towards  minimizing 
the  possibilities  and  dangers  of  fire. 

To  bring  together  those  scientifically  interested  in  the  sub- 
ject of  fire  prevention. 

To  arrange  periodical  meetings  for  the  discussion  of  practical 
questions  bearing  on  the  same. 

To  establish  a  reading  room,  library,  and  collections  for  pur- 
poses of  research,  and  for  supplying  recent  and  authentic  infor- 
mation on  the  subject  of  fire  prevention. 

To*  publish  from  time  to  time,  papers  specially  prepared  for 
the  committee,  together  with  records,  extracts,  and  translations. 

To  undertake  such  independent  investigations  and  tests 
of  materials,  methods,  and  appliances  as  may  be  considered 
advisable. 

The  committee's  Reports  on  Tests  with  Materials,  Methods 
of  Construction,  or  Appliances  are  intended  solely  to  state  bare 
facts  and  occurrences,  with  tables,  diagrams,  or  illustrations, 
and  they  are  on  no  account  to  be  read  as  expressions  of  opinion, 
criticisms,  or  comparisons. 

Many  of  the  tests  described  in  these  "  Red  Books  "  are  quite 
as  applicable  to  American  as  to  English  practice,  and  numerous 


EXPERIMENTAL   TESTING    STATIONS 


115 


references  will  be  made  throughout  this  volume  to  them,  in  dis- 
cussing materials  or  constructions. 

A  complete  list  of  the  "Red  Books  ".still  in  print,  and  the 
prices  of  same,  may  be  had  by  addressing  The  British  Fire  Pre- 
vention Committee,  8  Waterloo  Place,  Pall  Mall,  London, 
England. 

Standards  of  -Fire-Resistance.  —  The  International  Fire 
Prevention  Congress,  held  under  the  auspices  of  The  British  Fire 
Prevention  Committee  in  London,  July  6  to  9,  1903,  in  which 
twelve  foreign  and  three  colonial  governments  participated,  for- 
mally adopted  the  standard  requirements  for  fire-resisting  ma- 
terials and  constructions  suggested  by  The  British  Fire  Preven- 
tion Committee.  These  standards  were  designed  to  discriminate 
between  materials  and  constructions  affording  temporary,  partial, 
or  full  protection  against  fire,  in  order  that  all  materials  or 
constructions  could  be  classified  under  these  headings.  The 
requirements  or  limits  for  this  classification  were  based  on  experi- 
ence obtained  from  numerous  tests  and  investigations,  com- 
bined with  experience  gained  in  actual  fires.  Compare  with 
paragraph  "  Temperatures  exhibited  in  Fires  and  Conflagra- 
tions," page  192.  Due  consideration  was  given  the  questions 
of  limitations  of  building  practice  and  cost.  These  standard 
requirements  are  as  follows: 


STANDARD   TESTS  FOR  FIRE-RESISTING   FLOORS  AND 
CEILINGS. 


+* 

, 

1 

*o 

3 

li 

iv 

1 

III 

'•£  03  § 

Classification. 

1 

§t£ 

§* 

ill 

3  03  +* 

S^fco" 

a  0..8  5 

"c 

-3  c3 

jSf 

13  ® 

6&|| 

X 

S-" 

'c  % 

c3  o-r- 

3'§1 

£ 

Q53 

3a 

hS^^ 

g«3 

jy-aoa, 

Mins. 

Deg.  F. 

Sq.  ft. 

Mins. 

Temporary  protection  .  .  j 

A 
B 

45 

60 

1500 
1500 

Optional 
Optional 

100 
200 

2 

2 

Partial  protection  1 

A 
B 

90 
120 

1800 
1800 

112  Ibs. 
168  Ibs. 

100 
200 

2 
2 

Full  protection                   ] 

A 

150 

1800 

224  Ibs. 

100 

2 

B 

240 

1800 

280  Ibs. 

200 

5 

116 


FIRE   PREVENTION   AND   FIRE   PROTECTION 


STANDARD  TESTS  FOR  FIRE-RESISTING  PARTITIONS. 


J; 

( 

I 

i 

~ 

1 

III 

Classification. 

| 

o 

O  ~CO 

is 

Si 

ill 

|||| 

"3 

jjj 

g-2 

-gi 

•13-S 

02 

5« 

%* 

HS 

g£§ 

1-o-sl 

Mins. 

Deg.  F. 

Sq.  ft. 

Mins. 

Temporary  protection  .  j 

A 
B 

45 
60 

1500 
1500 

2  in.  and  under 
Optional 

80 
80 

2 
2 

Partial  protection  ] 

A 

90 

1800 

2j  in.  and  under 

80 

2 

B 

120 

1800 

Optional 

80 

2 

Full  protection  j 

A 

150 

1800 

2j  in.  and  under 

r\    .•          i 

80 

2 

B 

240 

1800 

Optional 

80 

5 

STANDARD  TESTS  FOR  FIRE  RESISTING  SINGLE  DOORS,  WITH 
OR  WITHOUT  FRAMES. 


1 

| 

1 

i-M 

o 

*^ 

"^  o  3 

Classification. 

1 

g-g 

8  S 

II 

jf  OS® 

^«s 

1 

3  -g 

1^ 

J3  « 
II 

ill 

•a*li 

Mins. 

Deg.  F. 

Sq.  ft. 

Mins. 

Temporary  protection  .  | 

A 
B 

45 

60 

1500 
1500 

2  in.  and  under 
Optional 

20 
20 

2 
2 

Partial  protection  | 

A 
B 

90 
120 

1800 
1800 

2£  in.  and  under 
Optional 

20 
20 

2 
2 

Full  protection  j 

A 

150 

1800 

2j  in.  and  under 
r\  ,•       i 

25 

2 

B 

240 

1800 

Optional 

25 

5 

These  standards  may  be  briefly  summarized  as  follows: 

a.  Temporary  Protection  implies  resistance  against  fire  for 
at  least  three-quarters  of  an  hour. 

b.  Partial  Protection  implies  resistance  against  a  fierce  fire  for 
at  least  one  hour  and  a  half. 

c.  Full  Protection  implies  resistance  against  a  fierce  fire  for 
at  least  two  hours  and  a  half.* 

*  For  complete  descriptions  of  testing  station  and  testing  methods  of  The 
British  Fire  Prevention  Committee,  see  page  129,  etc.,  of  report  of  the  Inter- 
national Fire  Prevention  Congress,  London,  1903. 


EXPERIMENTAL  TESTING   STATIONS  117 

Interest  of  Government  in  Tests  of  Materials.  —  The 

United  States  Treasury  Department,  through  the  office  of  the 
supervising  architect,  has  under  its  control  public  buildings  of  a 
value  exceeding  $200,000,000,  while  annual  expenditures  for 
similar  structures  exceed  $20,000,000.  It  has  been  estimated 
that,  if  these  buildings  were  to  be  insured,  the  annual  cost  to  the 
government  would  be  more  than  $600,000,  but  as  United  States 
government  buildings  are  not  insured,  their  stability  and  efficiency 
under  trial  by  earthquake  or  fire  become  of  vital  importance. 
The  highest  possible  standard  of  efficiency  commensurate  with 
economic  design  must  also  be  considered,  especially  as  public 
buildings  are  nearly  always  of  a  permanent  character. 

With  a  view,  therefore,  to  reducing  the  cost  but  improving  the 
quality  and  efficiency  of  materials  used  in  building  and  other  con- 
struction work,  an  appropriation  was  made  by  Congress  in 
1906-07  for  the  establishment  of  a  structural-materials  labora- 
tory. « 

United  States  Laboratories  at  St.  Louis,  Mo. —  The 
Structural-Materials  Testing  Laboratories  at  St.  Louis  were 
established  by  the  Federal  Government  to  conduct  systematic 
investigations  covering : 

1.  The  obtaining  of  information  concerning  the  nature  and 
extent  of  the  deposits  of  sand,  gravel,  and  stone  which  appear 
to  be  available  for  the  purpose  of  making  concrete  at  or  near  the 
centers  where  Government  building  and  construction  work  are 
to  be  undertaken. 

2.  The  collection  of  samples,  ranging  from  a  few  tons  to  a 
carload  in  quantity  of  these  sands,  gravels,  or  stone  which  would 
be  representative  of  the  larger  deposits  available  for  actual  use, 
and  the  shipment  of  these  samples  to  the  central  laboratory  at 
St.  Louis. 

3.  The  testing  of  these  materials,  not  only  by  chemical  and 
physical  examination  of  the  materials  themselves,  but  also  by 
mixing  them  with  a  typical  cement  and  using  these  mixtures 
in  the  making  of  blocks,  beams,  etc.,  of  concrete  and  reinforced 
concrete  under  a  variety  of  conditions. 

4.  The  testing  of  the  steel  used  in  making  the  reinforced 
concrete  masses. 

5.  The  seasoning  of  these  masses  for  different  periods  of 
time  under  a  variety  of  conditions. 

6.  The  testing  of  these  masses  from  time  to  time  in  such 
manner  as  to  determine  their  different  properties  and  their  suit- 
ability for  different  classes  of  building  and  construction  work.* 

*  See  United  States  Geological  Survey  Bulletin,  No.  329,  "Structural- 
Materials  Testing  Laboratories  at  St.  Louis,  Mo. 


118        FIRE   PREVENTION   AND   FIRE   PROTECTION 

The  thoroughness  with  which  this  undertaking  has  been  car- 
ried out  is  indicated  by  the  fact  that,  during  the  two  years  ending 
June  30,  1907,  no  less  than  35,500  tests  and  determinations  were 
made,  including  more  than  1000  concrete  beams  each  8  inches 
by  11  inches  by  13  feet,  representing  different  types  of  mixtures, 
reinforcement,  etc. 

Fire-resisting  Tests.  —  Another  series  of  investigations, 
which  is  still  under  way,  was  undertaken  at  the  request  of  the 
supervising  architect's  office,  namely,  inquiry  into  the  rates  of 
conductivity  and  fire-resisting  properties  of  various  structural 
materials  used  in  the  construction  of  public  buildings.  Such 
tests  have  been  conducted  by  the  St.  Louis  laboratories,  before 
mentioned,  in  cooperation  with  the  Underwriters'  Laboratory 
at  Chicago,  and  also  independently  at  the  Government  Testing 
Laboratory  at  Pittsburgh. 

Bulletin  No.  370  of  the  United  States  Geological  Survey,  "The 
Fire-resistive  Properties  of  Various  Building  Materials,"*  con- 
tains a  detailed,  illustrated  account  of  fire  tests  made  on  thirty 
panels  of  various  building  materials,  viz.,  mortar  building  blocks; 
common,  sand-lime,  and  hydraulic-pressed  brick;  gravel-,  cinder-, 
limestone-  and  granite-concrete;  glazed  and  partition  terra-cotta 
blocks;  and  limestone,  sandstone,  granite,  and  marble  building 
stone.  Although  the  results  are  only  partial,  and  therefore  in- 
conclusive, nevertheless,  they  are  of  great  value,  and  as  they  will 
be  referred  to  in  more  detail  in  Chapter  VII,  the  following  general 
description  of  the  test  conditions  is  quoted  from  Bulletin  No.  370. 

The  materials  were  subjected  to  the  direct  application  of 
heat  for  two  hours  and  were  then,  except  in  five  panels,  imme- 
diately quenched  with  water.  Wherever  possible,  tests  were 
made  to  determine  the  compressive  strength  of  the  materials 
after  this  treatment.  Temperatures  were  observed  at  intervals, 
and  the  behavior  of  the  materials  during  the  test  and  the  con- 
dition of  their  surfaces  before  and  after  the  heating  and  quench- 
ing were  noted.  Photographs  of  the  panels  were  taken  to  show 
the  effects  of  the  tests.  .  .  . 

The  conditions  under  which  these  tests  were  made  were 
unusually  severe,  and  none  of  the  material  passed  perfectly. 
The  temperatures  used  would  hardly  be  reached  in  an  ordinary 
fire.  It  was  recognized  from  the  beginning  that  these  tests 
would  not  be  comparable  with  those  made  by  other  investigators. 
The  relatively  few  tests  that  have  been  made  of  the  fire-resistive 

*  May  be  had  by  writing  Department  of  Interior,  United  States  Geological 
Survey,  Washington,  D.  C. 


EXPERIMENTAL   TESTING    STATIONS  119 

qualities  of  building  materials  nearly  all  consisted  of  subjecting 
floor  slabs  and  columns  to  the  heat  of  a  wood  fire.  There  is 
reason  to  believe  that  the  tests  herein  described,  made  in  a  gas 
furnace,  are  more  severe  than  the  tests  made  with  a  wood  fire, 
even  though  the  latter  show  higher  temperatures  and  last  longer. 
In  the  gas  furnace  the  flames  are  forced  by  a  blast  of  air  against 
the  panel  from  the  beginning  to  the  end  of  the  test;  with  a  wood 
fire  the  heat  fluctuates  and  falls  decidedly  when  the  furnace  door 
is  opened  and  fresh  fuel  is  added. 

The  average  temperature  attained  by  the  faces  of  the  panels 
ten  minutes  after  the  gas  was  lighted  was  about  324°  C.  (or 
615.2°  F.),  and  nearly  half  of  the  panels  had  been  subjected  to 
freezing  weather  just  prior  to  the  tests.  The  average  tempera- 
ture of  the  face  of  one  panel  of  building  blocks  rose  from  0°  to 
450°  C.  (32°  to  842°  F.)  in  the  first  ten  minutes  of  firing,  while 
that  of  another  panel  of  the  same  material  ranged  from  22°  to 
600°  C.  (71.6°  to  1112°  F.)  during  the  same  interval. 

Underwriters'  Laboratories,  Incorporated.  —  Under- 
writer's Laboratories,  Incorporated,  is  an  institution  operating 
under  the  direction  of  the  National  Board  of  Fire  Underwriters. 
Its  principal  offices  and  testing  station  are  located  in  Chicago. 
It  has  branch  offices  for  the  conduct  of  its  business  in  thirty-two 
other  cities  in  the  United  States  and  Canada.  The  Chicago 
plant  occupies  a  three-story  and  basement  building  of  fireproof 
construction  containing  something  over  20,000  square  feet  of 
floor  space  with  a  frontage  of  116  feet.  Yard  space  is  provided 
for  huts  and  large  testing  furnaces.  The  main  building  in 
Chicago  is,  perhaps,  the  best  example  in  America  of  absolutely 
fireproof  construction  furnished  with  fireproof  finish  and  equip- 
ment. It  has  been  designed  as  a  model  to  show  a  practical 
solution  of  many  of  the  problems  raised  by  the  enormous  and 
disproportionate  loss  by  fire  in  the  United  States.  No  wood  or 
other  combustible  material  is  used  in  any  portion  of  the  finish  or 
equipment.  In  addition,  the  plant  is  equipped  with  automatic 
sprinklers,  and  the  lighting  and  heating  hazards  are  safe- 
guarded with  every  known  precaution  applicable  to  their  instal- 
lation in  buildings  of  frame  construction.  From  this  description 
you  will  realize  that  in  this  case  the  Underwriters  have  gone  to 
the  extreme  in  adopting  in  their  own  property  all  of  the  measures 
they  are  known  to  recommend  in  the  property  of  others.  Forty- 
five  persons  are  employed  in  the  Chicago  plant,  which  has  a 
value  of  approximately  $100,000.00.  The  business  of  this  in- 
stitution is  the  examination  and  testing  of  appliances,  devices, 
systems,  and  materials  having  a  bearing  on  the  fire  hazard. 
These  include  appliances  designed  to  aid  in  extinguishing  fires 
such  as  automatic  sprinklers,  pumps,  hand  fire  appliances,  hose, 
hydrants,  nozzles,  valves,  etc.,  materials  and  devices  designed 
to  retard  the  spread  of  fire  such  'as  structural  methods  and 
materials,  fire  doors,  and  shutters,  fire  windows,  etc.;  and 
machines  and  fittings  which  may  be  instrumental  in  causing  a 
fire  such  as  gas  and  oil  appliances,  electrical  fittings,  chemicals 


120         FIRE   PREVENTION   AND   FIRE   PROTECTION 

and  the  various  machines  and  appurtenances  used  in  lighting 
and  heating. 

Up  to  the  present  time,  the  laboratories  have  examined  and 
issued  reports  on  over  five  thousand  different  subjects  or  appli- 
ances, each  report  representing  from  one  to  a  dozen  series  of 
investigations  and  experiments. 

Summaries  of  the  laboratories'  reports  are  promulgated  on 
printed  cards  filed  according  to  classifications,  and  cabinets 
containing  these  cards  are  maintained  at  the  offices  of  the  prin- 
cipal Boards  of  Underwriters  and  Inspection  Bureaus  in  the 
United  States,  at  many  of  the  general  offices  of  insurance  com- 
panies, by  some  insurance  firms,  certain  municipal  departments, 
and  at  the  local  offices  of  the  laboratories  in  large  cities.* 

Laboratories'    Factory  Labeling   System.  —  One   of   the 

most  important  functions  of  the  Underwriters'  Laboratories  is 
the  system  of  factory  inspection  and  labeling,  whereby  devices 
and  materials  employed  for  fire  prevention  or  fire  protection  may 
be  given  adequate  inspection  by  Laboratories'  engineers  at  the 
factory  where  made,  and  then  labeled  by  means  of  stamps, 
transfers,  or  metal  labels,  if  up  to  the  standard  requirements. 
For  this  purpose,  branch  offices  are  maintained  in  many  of  the 
principal  cities  of  the  United  States  and  Canada,  and  the  system 
has  met  with  such  favor  that  it  has  gradually  been  extended  to 
cover  many  standards,  such  as  electrical  conduits  and  fittings, 
extinguishers,  window  frames  for  wire  glass,  fire  doors  of  various 
kinds  and  uses,  hardware  for  windows  and  doors,  watch  clocks, 
hose,  shutters,  fire-retarding  paint,  fusible  links,  etc. 

The  cost  of  this  service  is  partially  defrayed  by  charges  made 
for  the  labels,  varying  according  to  the  nature  and  extent  of  the 
inspection  needed.  For  goods  which  can  be  tested  by  machinery 
or  which  are  machine  made  and  run  through  factories  in  such 
quantities  that  tests  of  a  number  of  samples  of  each  day's  out- 
put give  a  fair  criterion  of  the  whole  product,  the  charges  run 
from  fifty  cents  to  one  dollar  and  a  half  per  thousand  labels. 
For  goods  made  by  hand  and  goods  which  require  inspection  or 
test  of  each  individual  item,  the  charges  run  from  seven  and  one- 
half  cents  to  twenty-five  cents  per  label.  In  no  case  is  the  cost) 
of  the  inspection  service  as  represented  by  the  charge  for  the 
label  sufficient  to  become  a  factor  of  importance  in  determining 
the  selling  price  of  the  article  labeled. 

*  Extracts  from  address  delivered  at  Annual  Convention  of  the  Inter- 
national Association  of  Fire  Engineers,  Syracuse,  N.  Y.,  August,  1910,  by 
Mr.  William  H.  Merrill,  Manager  of  Underwriters'  Laboratories,  and  President 
National  Fire  Protection  Association. 


EXPERIMENTAL   TESTING    STATIONS  121 

The  extent  of  this  service  is  indicated  by  the  fact  that,  for 
the  year  ending  March  31,  1910,  no  less  than  16,815,920  labels 
were  supplied  to  inspectors  —  a  remarkable  showing  when  it  is 
remembered  that  the  service  has  only  been  in  operation  since 
1905.  The  value  of  this  service  is  three-fold: 

1.  It  forms  a  guarantee   to  the  insurance   companies   that 
allowances  made  by  them  for  preventive  or  protective  devices 
or  materials  are  based  on  the  use  of  approved  standards. 

2.  It  assures  the  purchaser  that  such  devices  or  materials 
can  be  fully  relied  on  in  so  far,  at  least,  as  the  manufacture  is 
concerned.     If  properly  used  and  maintained  by  the  purchaser, 
stated  reductions  in  insurance  rates  may  be  secured  for  preven- 
tive or  protective  devices. 

3.  It  protects  the  manufacturer  by  reducing  unfair  compe- 
tition,  in  that  the  label  service  requires  a  definite  standard 
from  all. 

Associated  Factory  Mutual  Laboratories.  —  The  experi- 
mental testing  laboratory  conducted  by  the  inspection  department 
of  the  Associated  Factory  Mutual  Fire  Insurance  Companies, 
at  Boston,  Mass.,  was  the  first  laboratory  of  note  in  the  United 
States  to  be  devoted  to  the  study  of  fire  protection  devices  and 
fire  protection  engineering.  It  was  started  in  1890,  and  has 
been  steadily  maintained  by  the  insurance  companies  interested. 
The  investigations,  comprise,  principally,  tests  of  fire  protection 
appliances  and  investigations  of  hazards  connected  with  manu- 
facturing risks. 

New  York  Building  Department  Tests. —  The  lack  of 
exact,  impartial  knowledge  respecting  many  of  the  various  sys- 
tems of  fireproofing  in  use,  led  Mr.  Stevenson  Constable,  then 
Superintendent  of  Buildings  in  New  York  City,  to  undertake  a 
series  of  exhaustive  tests  to  determine  the  comparative  merits  of 
the  more  important  methods  of  floor  construction,  and  in  1896 
he  asked  a  number  of  companies  to  submit  test  samples  of  their 
respective  constructions,  such  tests  to  be  uniform  in  requirements, 
and  official.  A  direct  comparison  could  thus  be  made,  at  once 
thorough  and  impartial. 

Vacant  lots  for  the  test  structures  were  secured  in  New  York 
City,  and  the  tests  were  conducted  by  the  officials  of  the  New 
York  Building  and  Fire  Departments.  The  kilns  or  test  houses 
were  built  according  to  plans  prepared  by  the  Building  Depart- 
ment, and  the  various  floor  companies  then  built  their  floors  over 


122 


FIRE    PREVENTION    AND    FIRE    PROTECTION 


these  chambers  (each  floor  being  about  14  feet  square)  under  the 
supervision  of  the  Building  Department  officials.  Care  was  taken 
to  secure  only  average  workmanship  and  materials  in  the  con- 
struction of  the  floors. 

Test  Kilns.  —  These  were  made  about  11  feet  by  14  feet  in 
size,  inside  measurement,  with  brick  walls  12  inches  thick,  re- 
inforced by  buttresses  and  iron  stays  (see  Fig.  30).  The  kilns 
were  10  feet  high  from  the  upper  or  main  grate-bars  to  the  floor 


FIG.  30.  —  Test-kilns  used  in  New  York  Building  Department  Tests. 

system  to  be  tested,  which  formed  the  roof  of  the  kiln.  Second- 
ary or  lower  grate-bars  were  placed  from  14  to  18  inches  below 
the  main  grate,  air  being  admitted  by  openings  in  the  walls 
below  the  lower  grate.  At  each  corner  of  the  kilns,  chimneys 
15  inches  square  were  constructed.  The  floor  samples  to  be 
tested  were  constructed  between  steel  beams  resting  on  the  brick 
walls.  All  ceiling  surfaces  or  under  sides  of  floor  systems  were 
plastered.  Wooden  sleepers,  with  concrete  or  cinder  filling  be- 
tween, were  laid  over  the  floor  arches  in  every  case,  but  no  fin- 
ished wood  flooring  was  used.  Care  was  taken,  as  before  stated, 
to  secure  only  average  samples,  such  as  would  be  used  in  ordinary 
building  construction,  and  in  some  instances  finished  samples 
had  to  be  replaced  by  the  manufacturer  on  account  of  more  than 
ordinary  refinement  in  the  work. 

Method  of  Testing.  —  The  central  panel  of  the  floor  system  was 


EXPERIMENTAL   TESTING    STATIONS  123 

loaded  uniformly  to  150  pounds  per  square  foot.  A  wood  fire 
was  then  started  on  the  grates  and  kept  burning  for  five  hours, 
the  temperature  during  the  last  four  hours  being  kept  as  nearly 
as  possible  to  2000°  F. ;  water  was  then  applied  through  a  If-inch 
nozzle  under  60  pounds  pressure,  by  the  officials  of  the  fire  de- 
partment. This  lasted  for  fifteen  minutes,  the  first  five  minutes 
being  on  the  ceiling  only,  and  the  remaining  ten  minutes  on  both 
ceilings  and  walls.  The  top  of  the  floor  was  next  flooded  with 
water  under  low  pressure  for  a  space  of  five  minutes.  At  the 
conclusion  of  the  fire  and  water  test,  the  original  load  was  re- 
moved, and  a  similarly  placed  load  of  600  pounds  per  square  foot 
was  substituted  and  maintained  for  forty-eight  hours.  This 
final  load  was  so  placed  as  to  rest  entirely  on  the  floor  arch,  and 
not  over  the  supporting  beams. 

The  temperatures  were  taken  by  means  of  pneumatic  pyrom- 
eters, placed  in  the  kiln  just  below  the  floor  system,  also  by 
placing  various  metals  with  known  melting  points  at  the  same 
positions.  Transit  observations  were  taken  to  determine  the 
combined  deflections  of  both  the  floor  beams  and  the  arches 
between  them. 

Present  Test  Requirements  of  New  York  Building  De- 
partment. —  Floors.  —  The  above  described  series  of  tests, 
some  of  which  are  described  in  detail  in  Chapters  XVII  and 
XVIII,  formed  the  basis  of  the  requirements  now  demanded  of 
fire-resisting  floors  by  the  Building  Code  of  the  City  of  New  York. 
Such  present  requirements  are  substantially  as  stated  above, 
except  that  the  fire  test  shall  comprise  "the  continuous  heat  of  a 
wood  fire  below,  averaging  not  less  than  1700°  F.  for  not  less  than 
four  hours,"  and  the  water  test  shall  consist  of  a  stream  of  water 
under  60  pounds  pressure  directed  against  the  under  side  of  the 
floor  construction  for  five  minutes,  then  flooding  the  top  of  floor 
under  low  pressure,  and  finally  applying  the  pressure  stream  as 
at  first  for  five  minutes  more. 

New  Materials.  —  The  New  York  Building  Code  also  states, 
in  section  20,  that  new  structural  material,  of  whatever  nature, 
shall  be  subjected  to  such  tests  to  determine  its  character  and 
quality  as  the  Superintendent  of  Buildings  shall  direct.  Under 
this  clause,  many  new  materials  and  constructions  have  been 
tested,  including  brick,  sand-lime  brick,  concrete  and  cement 
blocks,  fire-resisting  materials  used  for  trim  and  floor  surfaces, 
and,  especially,  partition  materials. 


124         FIRE    PREVENTION    AND    FIRE    PROTECTION 

Partitions.  —  The  requirements  for  acceptance  of  partition 
materials  are,  briefly,  that  they  be  tested  in  kilns  or  test  houses 
similar  to  those  previously  described,  and  that  "the  proposed 
partition  or  shaft  construction  must  be  subjected  to  a  continuous 
heat  from  a  wood  fire  for  at  least  one  hour.  An  average  tem- 
perature of  at  least  1700°  F.  must  be  maintained  during  the 
second  half-hour  of  the  test.  At  the  end  of  the  hour's  fire  test 
the  construction  is  to  be  subjected  to  a  stream  of  water  on  the 
inside  or  fire  side,  of  the  partition,  through  a  regulation  fire  hose, 
with  a  1  |-inch  nozzle,  for  a  period  of  two  and  one-half  minutes 
on  each  side.  The  nozzle  pressure  is  to  be  30  pounds  per  square 
inch.  At  no  time  during  the  test  must  fire  or  water  pass  through 
the  partition  under  test.  The  approval  of  the  construction  under 
test  may  be  withheld  if  the  construction  should  warp  or  bulge 
to  any  great  extent."  A  number  of  partition  tests  are  given  in 
detail  in  Chapter  XIII. 

The  "Columbia"  Fire  Testing  Station.— The  earlier  tests 
made  by  the  New  York  Building  Department,  as  previously 
described,  had  been  made  at  various  places  and  under  great 
expense,  principally  because  of  the  necessity  of  building  a  new 
test  structure  every  time  a  test  was  made,  and  of  procuring  an 
entirely  new  outfit  for  every  feature  of  the  test.  In  response, 
therefore,  to  the  demand  for  a  suitable  permanent  testing  station, 
where  tests  could  be  conducted  under  auspices  that  would  insure 
scientific  accuracy  and  absolute  impartiality,  the  "Columbia  Fire 
Testing  Station"  was  started  in  the  year  1903.  Although  the 
name  would  imply  that  the  station  was  conducted  by  Columbia 
University,  such  was  not  the  case.  It  was  organized  and  started 
by  Ira  H.  Woolson,  then  Adjunct  Professor  of  Civil  Engineering 
in  Columbia  University,  as  a  private  enterprise,  but  with  the 
sanction  of  the  University  Trustees,  and  with  the  approval  of 
the  New  York  Bureau  of  Buildings.  It  was  felt  that  if  such  a 
station  were  maintained  by  Professor  Woolson,  it  would  be  free 
from  any  criticism  as  to  favoritism,  and  that,  at  the  same  time, 
tests  could  be  conducted  from  time  to  time  under  exactly  dup- 
licating conditions.  Hence  the  majority  of  the  tests  made  at 
this  station  have  been  conducted  in  cooperation  with  the  New 
York  Bureau  of  Buildings. 

Since  the  retirement  of  Professor  Woolson  from  Columbia 
University,  to  become  associated  with  the  National  Board  of 
Fire  Underwriters,  the  testing  station,  as  well  as  the  former  work 


EXPERIMENTAL   TESTING   STATIONS  125 

of  Professor  Woolson,  is  now  in  charge  of  the  latter's  former 
assistant,  Mr.  J.  S.  Macgregor. 

Facilities.  —  The  facilities  of  the  testing  station  comprise  a 
building  for  testing  floors  up  to  a  span  of  20  feet,  and  another 
building  for  testing  partitions  of  a  size  10  by  14  feet,  with  all 
necessary  apparatus.  The  latter  building  is  also  used  for  testing 
doors,  windows,  shutters,  etc. 

Tests.  —  Full-sized  unit  tests  conducted  by  Professor  Woolson 
have  numbered  68,  47  of  which  were  made  at  the  Columbia 
station.  Twenty-one  have  been  made  elsewhere,  either  because 
the  station  was  in  use  with  other  tests  or  because  tests  were 
required  in  other  cities.  Of  the  total  number,  floors  comprised 
42,  partitions  23,  walls  1,  doors  and  shutters  2.  A  few  of  these 
have  been  published  in  pamphlet  form. 

Fire  Tests  in  German  Empire.*— In  1885  the  first  practical 
fire  tests  to  be  made  in  Germany  were  conducted  under  the  direc- 
tion of  Professor  Bauschinger  of  the  Technical  High  School  in 
Munich.  These  were  laboratory  fire  and  water  tests  on  unpro- 
tected wrought-  and  cast-iron  columns,  and  on  masonry  columns 
or  piers.  The  points  brought  out  were  the  superiority  of  cast- 
over  wrought-iron  columns,  and  of  brick  and  concrete  over  stone. 

In  Berlin,  1893,  under  the  direction  of  the  Berlin  Fire  Brigade, 
an  important  series  of  fire  tests  was  made  in  a  building  about  to 
be  torn  down,  in  which  various  rooms  were  fitted  up  to  resemble, 
as  closely  as  possible,  actual  conditions  in  stores,  shops,  living 
rooms,  etc.  The  objects  of  the  experiments  were  to  test  arrange- 
ments and  apparatus  for  the  prevention  of  fire,  materials  and 
systems  of  construction,  and  appliances  for  the  extinguishment 
of  fire.  The  main  points  striven  after  were  floors,  ceilings,  doors, 
and  staircases  of  the  greatest  possible  fire  resistance,  and  the 
restriction  of  the -great  danger  of  smoke  to  as  small  an  area  as 
possible.  Prizes  and  diplomas  were  awarded  many  builders  and 
manufacturers. 

Tests  in  Hamburg  (following  a  disastrous  fire  in  a  dock  ware- 
house) were  made  in  1895  on  various  details  of  warehouse  con- 
struction, especially  columns  and  protective  coverings  for  same. 
The  tests  resulted  in  the  decision  to  continue  the  use  of  wrought- 

*  For  a  more  detailed  description  see  article  "Testing  Methods  at  the 
Royal  Technical  Research  Laboratory  at  Charlottenburg,  etc.,"  by  F.  Jaffe", 
Crown  Architect,  Berlin,  in  report  of  International  Fire  Prevention  Congress, 
London,  1903. 


126         FIRE   PREVENTION   AND   FIRE   PROTECTION 

iron  columns  in  warehouse  construction,  but  to  protect  such 
members  by  fire-resisting  coverings.  The  question  whether 
open  latticed  columns,  etc.,  should  be  filled  with  cement  or  con- 
crete, before  being  encased,  was  decided  in  the  negative. 

A  permanent  testing  station,  supported  by  the  state,  is  main- 
tained at  Berlin  under  the  name  of  the  Royal  Technical  Research 
Laboratory.  Test  huts,  similar  to  those  used  by  the  British 
Fire  Prevention  Committee  are  used,  and  an  official  certificate 
is  issued  for  each  test  of  material  or  device. 

Detailed  Tests  of  Materials  and  Constructions.  —  The 
materials  usually  employed  in  fire-resisting  construction  are 
described  in  detail  in  Chapter  VII,  where  will  also  be  found 
descriptions  of  many  fire  and  water  tests  made  under  the  auspices 
of  testing  stations  previously  described. 

Tests  of  devices  or  constructions  will  be  found  in  various  fol- 
lowing chapters,  where  such  tests  may  be  more  properly  con- 
sidered in  connection  with  the  construction  or  device  under 
discussion. 


CHAPTER  VI. 

FIRES  IN    FIRE-RESISTING   BUILDINGS,   AND    CON- 
FLAGRATIONS. 

FIRE  LOSSES  ON  FIRE-RESISTING  BUILDINGS. 

EVERY  fire  teaches  some  lesson;  every  great  fire  some  great 
lesson  —  to  the  discerning,  at  least.  The  practical  value  may 
be  trifling,  adding  but  one  more  instance  to  the  statistics  of  fire 
cause  and  effect,  or  the  lesson  may  be  of  momentous  importance, 
causing,  through  its  very  calamity  and  wide-spread  effects,  the 
enforcement  of  more  stringent  regulations  pertaining  to  fire 
hazard,  or  even  the  introduction  of  radical  changes  in  the  build- 
ing construction  of  an  entire  city.  Indeed,  it  is  not  an  exaggera- 
tion to  say  that  a  single  conflagration  brought  about  a  hew 
fire-resisting  construction  throughout  a  whole  nation,  as  our 
own  present  forms  of  structural  fireproofing  are  practically  the 
immediate  outcome  of  the  great  Chicago  fire. 

London,  through  its  Cripplegate  disaster,  and  Chicago, 
through  its  conflagration  of  1871,  both  learned  the  folly  of  allow- 
ing firetrap  structures  to  menace  the  safety  of  a  great  city. 
Jacksonville  learned  to  its  sorrow  that  dynamite  is  a  poor  sub- 
stitute for  water  in  fighting  fire  —  but  not  until  a  large  portion 
of  the  city  had  been  devastated  in  spite  of  a  river,  capable  of 
furnishing  an  adequate  water  supply,  within  easy  range  of  its 
main  thoroughfares.  Waterbury,  Conn.,  and  Paterson,  N.  J., 
gained  costly  experience  as  to  the  neglect  of  fire  hazard,  while 
Baltimore  and  San  Francisco  must  still,  for  a  long  time  to  come, 
be  engaged  in  replacing  the  enormous  losses  which  came  from 
neglecting  previous  well-defined  warnings  as  to  the  absolute 
necessity  of  fire-resisting  construction  in  congested  areas,  and 
adequate  provision  against  exposure  fires. 

But  our  knowledge  concerning  fire  causes  and  effects  has  not 
been  confined  to  great  conflagrations.  Hardly  less  important 
have  been  the  lessons  taught  by  fires  in  individual  buildings. 
Paris  sacrificed  124  lives  in  its  terrible  bazaar  fire  before  it  realized 

127 


128        FIRE   PREVENTION   AND   FIRE   PROTECTION 

that  a  safe  place  of  amusement  for  large  crowds,  even  though  of 
a  purely  temporary  character,  could  not  be  constructed  in  a 
night.  London,  as  late  as  1902,  was  only  brought  to  a  realiza- 
tion of  its  antiquated  fire  department  through  the  fire  in  a  five- 
storied  building  on  Queen  Victoria  Street,  where  ten  persons  lost 
their  lives  because  50-foot  ladders  would  not  reach  to  a  height 
of  60  feet.  The  Jefferson  Hotel  at  Richmond,  Va.,  patronized 
by  scores  of  winter  tourists  in  the  belief  that  the  structure  was 
fireproof,  came  to  complete  ruin  because  of  a  poorly  insulated 
wire,  combined  with  a  construction  far  from  fire-resisting;  while 
the  Hotel  Windsor  fire  in  New  York,  and  the  Iroquois  Theater 
fire  in  Chicago,  served  to  bring  home  to  those  cities  the  fact  that 
firetrap  hotel  construction,  and  totally  inadequate  theater  pro- 
tection and  equipment,  are  both  nothing  short  of  criminal. 

To  the  above-mentioned  fires  may  be  added  those  still  more 
valuable  experiences  from  fires  which  have  occurred  in  buildings 
intended  to  be  fire-resisting,  —  such  as  the  Chicago  Athletic 
Club  building,  the  Home  buildings  in  Pittsburgh,  the  Granite 
building  in  Rochester,  and  others  of  similar  character  —  and 
conflagrations  such  as  Baltimore  and  San  Francisco  where  fire- 
resisting  structures  have  been  subjected  to  the  test  of  confla- 
gration conditions.  To  those  interested  in  fire  protection  and 
fire-resistive  building  construction,  these  actual  tests  of  improved 
methods  are  of  the  greatest  value,  and  it  will  be  the  object  of 
this  chapter  to  consider  some  of  the  more  important  fires  of  this 
character  with  a  view  to  determining  the  lessons  made  manifest. 

Fire  and  Water  Tests  Classified.  —  Our  present  knowledge 
of  the  action  of  fire  and  water  upon  buildings  or  building  materials 
and  devices  is  derived  from  four  principal  sources: 

First:  Experimental  tests,  as  enumerated  in  Chapters  V, 
VII,  etc. 

Second:  From  fires  in  non-fire-resisting  buildings,  neither 
built  as,  nor  claiming  to  be  of  fire-resisting  construction.  Such 
fires  are  generally  interesting,  if  studied  carefully,  as  illustrating 
the  often  eccentric  behavior  of  fire,  and  are  apt  to  be  valuable 
in  determining  the  cause  of  fire,  or  its  effects  upon  the  particular 
arrangement  or  planning  of  the  building,  or  upon  the  materials 
employed.  Such  examples  are  not  particularly  valuable  to  the 
advocates  of  fire-resisting  construction,  except  in  so  far  as  they 
serve  to  show  the  utter  unreliability  of  any  type  other  than  fire- 
resistive.  The  Paris  bazaar,  the  Hotel  Windsor,  the  London 


FIRES   IN   FIRE-RESISTING    BUILDINGS  129 

fire,  etc.,  are  examples  of  this  class  —  all  teaching  a  valuable 
moral,  but  still  forming  no  test  of  modern  fire-resisting  methods. 

Third:  From  fires  in  buildings  which  are  not  fire-resistive, 
and  which  were  never  intended  to  be  so,  but  which,  neverthe- 
less, are  popularly  so  considered  by  those  not  thoroughly  ac- 
quainted with  fire-resisting  principles,  who  are  often  misled  by 
those  half-way  makeshifts,  —  hotels,  apartment  houses,  and 
even  commercial  buildings  —  which  are  advertiped  or  spoken 
of  as  " thoroughly  fireproof"  when  their  construction  in  no  way 
warrants  such  a  claim. 

In  this  class  are  included  also  those  structures  of  earlier  dates 
which  are  still  judged  as  representative  of  modern  construction, 
and  which,  after  failure,  lead  many  to  misjudge  completely  true 
fire-resisting  construction  and  to  lose  faith  in  fire-resisting  efforts 
in  general.  A  most  excellent  example  of  this  character  was 
afforded  by  the  burning  of  the  Manhattan  Savings  Bank  building 
in  New  York  in  1895.  This  fire,  originating  in  and  spreading 
from  a  building  across  the  street,  very  thoroughly  destroyed  the 
Manhattan  Bank  building,  which  "  while  far  from  representing 
the  best  fireproof  construction,  would  ordinarily  be  called  fire- 
proof by  builders,  landlords,  and  the  public  generally."*  As  a 
matter  of  fact,  no  one,  at  all  acquainted  with  the  most  rudi- 
mentary knowledge  of  fire-resistance,  could  have  considered  this 
building  fire-resisting,  owing  to  the  unprotected  cast-iron  columns 
and  bottom  flanges  of  floor  girders.  Nevertheless,  this  fire  in  a 
"fireproof"  building  was  the  cause  of  many  criticisms  shortly 
thereafter,  in  which  the  entire  system  of  fire-resistance,  as  then 
practiced,  was  assailed  by  critics  in  general  and  fire-department 
officials  in  particular.  A  prominent  fire-department  chief  was 
quoted  as  saying  that  there  was  not  then  a  thoroughly  fireproof 
building  in  New  York  City.  Also  "the  Manhattan  Bank  fire 
shows  that  so  little  fireproof  are  these  structures  that  they  are 
susceptible  to  fire  from  without  and  but  fifty  feet  away  from 
them.  The  heat  from  the  Keep  building  acted  directly  upon  the 
exposed  iron  work  of  the  Manhattan  building.  The  iron  re- 
sisted the  fire  —  that  is,  it  did  not  blaze  —  but,  so  far  as  the 
safety  of  the  building  was  concerned,  it  did  something  infinitely 
worse.  It  expanded  under  the  heat,  and  forced  out  the  ends  of 
the  iron  beams  and  girders  from  their  resting  places  on  the  sup- 
porting piers."  Surely,  when  firemen,  builders,  landlords,  or 
*  See  Engineering  News,  Vol.  XXXV,  No.  16. 


130         FIRE   PREVENTION   AND   FIRE    PROTECTION 

any  portion  of  the  general  public  consider  this  fire-resisting  con- 
struction, —  and  that  such  is  the  case  even  today,  the  writer 
knows  from  personal  conversations  —  it  is  no  wonder  that  there 
is  discouragement  from  such  tests. 

Fourth:  Fortunately,  however,  we  still  have  a  fourth  source 
of  knowledge  respecting  fire  tests,  namely,  through  those  fires 
which  have  occurred  in  buildings  designed  and  constructed  to 
resist  fire  more  or  less  in  accordance  with  the  best  and  most 
approved  methods  in  use  at  the  time  of  erection. 

Manifestly  such  tests  of  actual  fire  under  actual  conditions  are 
of  far  greater  value  than  mere  experimental  tests.  No  prepara- 
tion is  made  for  some  expected  result;  no  opportunity  is  pre- 
sented to  minimize  the  effects.  The  devastation  is  quick,  the 
conditions  practical,  the  results  conclusive,  but  not  without 
loss  —  often  very  great  loss —  even  though  the  building  was  fire- 
resistive.  As  well  expect  the  contents  of  a  stove  to  refuse  to 
burn,  or  the  grate-bars  to  burn  out,  simply  because  the  stove  is 
incombustible. 

As  in  the  case  of  the  Manhattan  Bank  building,  many  fires 
have  occurred  in  buildings  termed  fire-resisting,  which  are  not 
worth  careful  attention  as  regards  fire-resisting  methods,  simply 
because  more  was  claimed  for  such  structures  than  their  con- 
struction warranted.  A  number  of  fires  have  occurred,  however, 
in  buildings  worthy  of  the  appellation  of  fire-resisting,  or  at  least 
as  the  term  was  known  at  the  time  of  building,  and  these,  while 
greatly  to  the  credit  of  modern  methods  in  most  particulars, 
still  reveal  glaring  faults,  deplorable  makeshifts,  and  many 
lessons  of  great  value  for  future  guidance. 

First  Actual  Test  of  Fire-resisting  Construction.  —  It  is 
somewhat  difficult  to  determine  exactly  what  building  might  be 
considered  the  first  fire-resisting  structure  to  suffer  test  by  fire; 
but  as  modern  types  of  terra-cotta  arch  construction  did  not 
become  at  all  common  until  the  early  eighties,  and  as  the  first 
purely  skeleton  construction  building  was  not  erected  until 
1884-85,  the  first  test  really  applicable  to  modern  methods  of 
construction  must  be  found  subsequent  to  those  years. 

A  number  of  fires  had  previously  occurred  in  semi-fire-resisting 
buildings,  all  pointing  to  the  great  value  of  such  construction, 
but  still  not  affording  a  test  of  fireproof  methods  per  se.  Such 
was  the  fire  in  the  Chicago  Opera  House,  where  a  non-fireproof 
roof  was  destroyed  with  the  ornamental  portions  of  the  interior, 


FIRES    IN    FIRE-RESISTING    BUILDINGS  131 

leaving  the  structural  parts  below  the  roof  uninjured.  Such, 
also,  was  the  fire  in  the  Stillman  apartment  house  in  Cleveland, 
where  an  unfireproofed  roof  construction  was  destroyed  without 
damage  to  the  fire-resisting  floors  below.  But  it  was  not  until 
1891  that  a  really  adequate  test  of  fire-resisting  methods  was 
afforded,  and,  strangely  enough,  the  fire  could  not  have  been 
better  planned  for  such  a  test  had  the  structure  been  actually 
designed  and  built  for  this  especial  purpose.  This  fire  was  in  the 
Minneapolis  Lumber  Exchange  building. 

Minneapolis  Lumber  Exchange  Fire.*  —  This  fire,  which 
occurred  in  January,  1891,  afforded  a  most  valuable  and  inter- 
esting comparison  of  non-fire-resisting  and  fire-resisting  con- 
structions in  one  and  the  same  building,  for,  although  the  fire 
was  principally  confined  to  the  " slow-burning"  original  portion 
of  the  structure,  still  the  contrast  between  this  portion  and  a 
thoroughly  fire-resisting  addition  formed  a  contrast  seldom  seen. 

The  building  originally  consisted  of  a  nine-storied  slow-burning 
structure,  so  called  because  all  of  the  iron  columns  and  girders 
and  the  wooden  floor  joists  were  covered  with  fireproof  tile.  To 
this  portion  were  added  two  new  stories,  making  eleven  in  all, 
and  an  entirely  new  portion,  also  of  eleven  stories.  Both  of 
these  additions  were  designed  to  be  of  approved  fire-resisting 
construction,  built  of  masonry  walls  and  a  steel  framework  with 
five-inch,  hollow-tile  floor  arches,  carried  on  floor  I-beams,  spaced 
about  seven  feet  centers. 

The  fire  started  in  a  five-storied  paint  store  separated  from 
the  old  Exchange  by  only  a  twelve-foot  alleyway,  and  thus,  with- 
out design,  the  conditions  were  afforded  for  a  most  compre- 
hensive test  case  —  an  inflammable  building  in  which  the  fire 
originates,  an  adjacent  slow-burning  structure,  and  the  new 
fireproofed  portions. 

In  the  older  portion  of  the  building  the  fire  burned  for  twenty- 
four  hours,  leaving  only  the  bare  walls  and  the  iron  columns 
which  supported  the  two  new  stories.  These  columns  still  re- 
tained enough  of  their  fireproofing  to  prevent  failure,  and  the 
curious  spectacle  was  presented  of  two  comparatively  uninjured 
stories  over  and  above  nine  stories  of  complete  ruin.  The  over- 
head tenth-  and  eleventh-story  floor  arches  remained  practically 
perfect,  except  that  the  plastering  was  wholly  destroyed,  although 

*  For  very  interesting  photographs  of  this  fire,  see  Inland  Architect,  August, 
1891. 


I 


132         FIRE    PREVENTION    AND    FIRE    PROTECTION 

the  stone  trimming  around  the  windows  was  badly  crumbled  in 
many  instances.  Nine  stories  of  fire  under  a  fire-resisting  floor 
construction  would  constitute  a  challenge  which  not  many  manu- 
facturers, possibly  even  of  terra-cotta,  would  choose  to  accept 
even  today. 

The  new  building,  connected  to  the  older  portion  by  thirty-five 
foot  openings  on  each  floor,  was  not  entirely  finished.  The  plas- 
tering had  been  completed  and  many  of  the  rooms  contained  more 
or  less  wood  trim  which  was  about  to  be  placed,  this  fact  doubt- 
less contributing  to  the  very  slight  damage  done.  While  no 
portion  of  this  addition  suffered  either  as  intense  or  as  direct 
heat  as  did  the  tenth  floor  of  the  older  part,  still  the  effects  of  the 
burning  of  such  quantities  of  wood  joists  and  girders  in  the  " slow- 
burning"  portion  was  evidenced  by  the  blackened  walls  and 
ceilings,  caused  by  the  flame  and  smoke  pouring  through  the 
connecting  openings;  and  had  the  wood  trim  been  all  in  place, 
or  the  construction  of  a  less  incombustible  nature,  the  damage 
would  have  been  far  greater  than  it  was.  Even  within  five  feet 
of  the  connecting  openings  the  plastering  was  found  intact,  and 
in  spite  of  the  subsequent  freezing  of  the  water  poured  upon  the 
floors,  and  the  great  and  rapid  changes  in  temperature  caused 
thereby,  neither  the  floor  arches  nor  any  of  the  structural  por- 
tions of  the  newer  addition  seemed  to  have  been  seriously  affected 
in  any  way.  Had  the  fire,  in  its  early  stages,  been  attacked  from 
the  inside  of  the  new  building  at  the  various  floor  levels  instead 
of  from  the  outside  only,  as  was  done,  still  less  damage  would 
have  resulted  with  probably  very  little  or  none  at  all  in  the  new 
structure. 

Although  many  reports  of  this  fire  stated  that  a  fireproof 
building  had  been  burned  and  destroyed,  it  is  seen  that  such 
statements  are  incorrect.  The  "  slow-burning "  construction, 
considered  good  and  efficient  in  its  day,  was  tried  and  found 
wanting,  while  the  newer  practical  system  of  fireproofing  ful- 
filled all  expectations.  No  greater  contrast  than  this  test  could 
be  desired. 

Metropolitan  Opera  House  Fire.  —  The  fire  which  de- 
stroyed the  stage  and  auditorium  of  the  Metropolitan  Opera 
House  in  New  York  City  on  August  27,  1892,  is  both  interesting 
and  instructive,  forming,  as  it  did,  one  of  the  earliest  examples 
of  a  fire  in  a  building  designed  to  be  fire-resisting,  and  also  the 
first  example  of  fire-resisting  theatre  construction.  The  writer 


FIRES    IN    FIRE-RESISTING    BUILDINGS  133 

was  informed  by  Mr.  Rudolf  Ballin,  formerly  in  charge  of  the 
inspection  of  theaters  for  the  New  York  Board  of  Fire  Under- 
writers, that  this  theater  was  the  first  to  be  constructed  entirely 
along  fire-resisting  lines,  and  from  an  underwriter's  standpoint 
it  was  regarded  with  great  interest  because  of  the  largely  experi- 
mental nature  of  applying  fire-resisting  methods  to  theater  con- 
struction, even  as  late  as  the  early  nineties.  Many  of  the  details 
employed  would  not  now  be  so  designed,  much  less  permitted. 
Construction  of  Building.  —  The  floor  construction  was  partly 
of  brick  arches,  sprung  between  beams,  but  mostly  of  8-inch  and 
10-inch  porous  terra-cotta  arches.  The  iron  stage  supports,  of 
a  very  extensive  and  intricate  design,  were  unprotected  through- 
out —  as  is  generally  the  case,  due  to  the  frequent  changes  made 
necessary  in  the  production  of  elaborate  grand  opera.  The 
cast-iron  columns  supporting  the  various  tiers  of  boxes  and  bal- 
conies were  unprotected,  but  the  large  girder  spanning  the  pros- 
cenium arch  was  protected  by  three  inches  of  porous  tile. 

Serious  defects  in  general  design  existed.     The  stage  portion 

was  not  properly  divided  from  the  auditorium,  as  the  openings 

in  the  proscenium  wall  were  only  protected  by  single  doors, 

ome  of  iron  and  some  of  wood.     The  fire  curtain  was  not  prop- 

rly  hung,  and  the  skylights  over  the  stage  did  not  work  auto- 

natically.     The  greatest  defect,   however,   consisted  of  shafts 

unning  between  the  stage  proper  and  the  dressing-room  portion 

f  the  stage,  with  sash  windows  on  each  floor,  while  the  elevator 

haft  also  had  open  communication  with  each  floor  of  the  dress- 

ng-room  section. 

Effects  of  the  Fire.  —  The  fire  occurred  in  the  daytime,  while 
he  theater  was  closed  to  the  public  for  the  summer,  and  was 
•robably  due  to  the  carelessness  of  a  scene  painter.  When  the 
iremen  first  entered  the  auditorium  the  stage  portion  was  burn- 
ng  fiercely,  the  auditorium  being  filled  with  smoke,  but  then 
untouched  by  flame.  Soon,  however,  the  flames  burst  through 
he  arch  into  the  body  of  the  house,  doing  far  more  damage  to 
he  upper  balconies  than  to  the  lower  ones  or  to  the  main  floor. 
The  chairs  in  the  lower  boxes  were  but  slightly  damaged,  while 
a,  level  false  floor  which  was  in  place  over  the  entire  pitched  main 
loor  (used  for  balls,  etc.)  was  not  seriously  injured  except  by 
he  debris  falling  on  it.  In  the  upper  balconies,  however,  the 
lamage  was  much  more  serious.  This  is  particularly  interesting  as 
orming  a  striking  comparison  with  the  Iroquois  Theater  disaster. 


134         FIRE    PREVENTION    AND    FIRE    PROTECTION 

• 

The  fire  fed  chiefly  on  a  mass  of  inflammable  scenery  upon 
the  stage,  also  upon  large  quantities  of  old  scenery  stored  be- 
neath it.  The  stage  portion  was  completely  burned  out,  and 
everything  of  a  combustible  nature  in  the  auditorium  above  the 
orchestra  floor  was  destroyed.  The  insurance  on  the  building 
was  only  $26,000,  this  loss  being  total.  The  insurance  on 
contents  was  $49,500,  the  insurance  loss  on  contents  being 
$48,668. 

As  to  the  structural  portions  of  the  building,  the  terra-cotta 
arches  of  the  main  floor  and  of  the  balconies  sustained  no  serious 
injury  other  than  the  loss  of  their  plaster  coverings.  The 
terra-cotta  fireproofing  around  the  proscenium  arch  girder  also 
remained  intact,  undoubtedly  preventing  the  collapse  of  the 
girder.  The  efficiency  of  the  general  employment  of  fire-resist- 
ing construction  was  demonstrated  by  the  complete  preservation 
of  the  adjoining  portions  of  the  building  from  injury,  as  not- 
withstanding the  severe  fire  on  the  stage,  the  hotel,  ball  rooms, 
restaurants,  etc.,  within  the  same  structure  were  untouched. 
"The  fire  afforded,  therefore,  a  valuable  demonstration  of  the 
worth  of  fireproof  construction,  since  without  it  the  entire  block 
would,  in  all  probability,  have  been  destroyed." 

Defects  in  Plan  and  Construction.  —  Lessons  of  value  are  to  be 
found  in  the  weakness  of  design  caused  by  the  introduction  of 
shafts  between  the  stage  and  dressing  rooms,  in  the  serious 
bending  and  deflection  of  the  unprotected  cast-iron  columns 
supporting  the  balconies,  in  the  failure  of  the  sprinkler  system 
to  overcome  the  fire,  due  to  inadequate  supply  of  water  from  the 
roof  tank,  in  the  failure  to  lower  the  asbestos  curtain,  although 
several  employes  were  on  or  ne'ar  the  stage,  including  two  of  the 
regular  house  firemen,  and  in  the  failure  of  the  skylights  over 
the  stage  to  provide  an  adequate  and  ready  vent  for  the  flame 
and  hot  air.  In  view  of  several  of  the  same  defects  in  the  more 
recent  Iroquois  Theater  fire,  the  following  comment  upon  the 
Metropolitan  Opera  House  fire,  published  in  the  Engineering 
Record  of  September  10,  1892,  will  serve  to  show  how  little  the 
lessons  of  past  experience  are  appreciated:  "The  experience  ol 
this  fire  seems  certainly  to  call  for  a  positive  exclusion  of  so  much 
inflammable  matter  on  or  near  the  stage,  and  improvement  in 
the  mechanical  appliances  t-Q  render  the  action  of  skylights  anc 
drop  curtains  automatic,  in  that  such  mechanisms  may  be  set  in 
motion  by  the  effect  of  the  heat." 


FIRES   IN    FIRE-RESISTING    BUILDINGS  135 

Chicago  Athletic  Club  Building  Fire.  —  This  fire,  which 
occurred  on  November  1,  1892,  is  generally  considered  the  first 
severe  test  by  fire  of  a  building  intended  to  be  fire-resisting,  and 
the  lessons  which  were  so  plainly  made  manifest  undoubtedly 
did  more  than  almost  any  other  fire  in  a  building  of  modern 
construction  to  call  attention  to  many  errors  of  detail,  and  to 
stimulate  efforts  toward  improvement  in  fire-resisting  methods. 

The  building  was  nine  stories  in  height,  and  devoted  exclu- 
sively to  the  purposes  of  the  athletic  club.  The  construction 
consisted  of  self-supporting  exterior  walls,  an  interior  steel 
frame  of  Z-bar  columns  and  I-beams,  porous  terra-cotta  "  end- 
construct  ion "  floor  arches,  and  partitions  and  column  coverings 
of  the  same  material. 

But,  unfortunately,  the  full  efficiency  of  this  fire-resisting 
groundwork  was  largely  nullified  by  introducing  large  quantities 
of  combustible  materials,  which,  while  possibly  demanded  by 
the  interior  appointments  of  comfort  and  elegance  expected  in 
clubhouse  design,  were  still  rendered  even  more  hazardous 
through  the  faulty  details  attendant  upon  their  use.  Thus  the 
gymnasium,  on  the  fourth  floor,  where  the  fire  originated,  was  a 
large,  two-storied  room,  finished  in  oak  paneling  throughout, 
the  ceiling  being  attached  to  one-inch  nailing  strips,  which  were 
so  fastened  to  the  terra-cotta  arch  blocks  as  to  leave  spaces 
between  the  floor  arches  and  the  paneling,  in  which  air  currents 
and  flame  could  freely  circulate.  This  same  construction  was 
followed  in  the  paneled  oak  wainscoting,  extending  from  floor 
to  ceiling  in  the  same  room,  and  also  in  all  corridors  in  which 
oak  wainscoting  was  used  to  a  height  of  five  feet. 

Another  serious  mistake  in  detail  was  the  introduction  of 
wooden  nailing  strips  between  the  successive  courses  of  the  terra- 
cotta blocks  used  for  column  casings.  In  order  to  provide 
grounds  for  the  oak  paneling,  2-inch  by  4-inch  wood  strips,  about 
3  feet  centers  vertically,  were  inserted  in  the  terra-cotta  column 
coverings,  the  construction  thus  consisting  of  alternate  courses 
of  four-inch  exposed  wood  strips,  and  three  feet  of  terra-cotta 
blocks.  The  result  was  precisely  what  might  have  been  ex- 
pected. As  soon  as  the  fire  burned  through  the  paneling  to  the 
wood  grounds,  these  also  were  consumed,  thus  allowing  the  tile 
to  fall,  and  exposing  the  steel  columns. 

The  Fire  —  started  in  the  gymnasium  before  the  building  was 
finished.  Large  quantities  of  wood  trim  for  other  portions  of 


136         FIRE   PREVENTION   AND   FIRE   PROTECTION 

the  building  were  stored  in  this  room  at  the  time,  and  such  a 
large  quantity  of  combustible  material  naturally  resulted  in  a 
very  severe  fire.  The  flames  were  rapidly  communicated  to  the 
upper  floors  by  means  of  the  windows  and  stairway  openings, 
completely  consuming  all  wood  finish,  and  destroying  all  plas- 
tering, electric  wiring,  and  piping,  besides  causing  considerable 
structural  damage.  The  costly  carved-stone  front  was  ruined 
above  the  third  floor,  a  few  steel  beams,  where  the  fireproofing 
had  not  been  completed,  were  deflected,  two  columns  on  the 
eighth  floor  were  badly  warped,  and  great  damage  was  done  to 
the  terra-cotta  partitions  and  column  coverings. 

Of  the  terra-cotta  floors,  none  failed  although  the  under  sides 
of  the  blocks  fell  off  in  some  instances.  Tests,  on  several  of  the 
apparently  worst  damaged  arches  after  the  fire,  developed  a  load 
of  450  pounds  per  square  foot  without  failure.  Many  of  the 
damaged  ceilings  were  repaired  by  means  of  expanded  metal  and 
plaster  attached  to  the  beams  and  to  the  damaged  tile. 

The  tile  partitions  showed  very  poor  resistance  to  the  force 
of  fire  hose,  thus  demonstrating  the  necessity  for  better  partition 
construction.  About  half  of  the  column  coverings  dropped  off, 
but  in  spite  of  such  a  poor  showing  the  steel  frame  was  entirely 
reused,  except  the  few  beams  and  columns  previously  noted. 
The  report  made  to  the  building  committee  included  the  follow- 
ing: "We  have  nowhere  discovered  that  the  metal  portions  of 
the  building,  where  the  fireproofing  held,  have  been  deformed  or 
injured.  And  even  where  the  fireproofing  tile  dropped  off,  from 
the  burning  out  of  the  nailing  strips  which  supported  them,  the 
columns  seem  to  have  supported  their  loads  without  bending, 
except  two  on  the  eighth  floor,  owing,  no  doubt,  to  the  fact  that 
the  greatest  heat  had  been  expended  before  the  strips  were  so 
burned  away  as  to  permit  the  tile  covering  to  drop  off.  This 
building  furnishes  an  assurance  that  was  lacking  before,  namely, 
that  the  metal  portions  of  a  building,  if  thoroughly  protected  by 
fireproofing  properly  put  on,  will  safely  withstand  any  ordinary 
conflagration.  In  this  instance  we  do  not  think  that  the  fire- 
proofing  was  properly  bonded.  The  integrity  of  the  building 
does  not  seem  to  be  impaired,  and  it  may  be  made  as  good 
as  new  by  replacing  the  parts  injured." 

Defects  in  Design.  —  It  will  thus  be  seen  that  the  first  severe 
test  of  modern  fire-resisting  methods  vindicated  the  use  of  steel- 
frame  and  terra-cotta  construction,  but  that  faulty  details  were 


FIRES   IN   FIRE-RESISTING   BUILDINGS  137 

responsible  for  the  damage  which  ensued.  Had  the  columns 
been  properly  protected  by  solid  and  continuous  casings,  with- 
out the  introduction  of  wood  strips,  it  is  very  improbable  that 
any  injury  whatever  would  have  resulted  to  the  columns  them- 
selves. Had  the  oak  wainscoting  and  ceiling  paneling  been  of 
incombustible  material,  or  even  thoroughly  back  plastered  so 
as  to  fill  all  air  spaces,  great  damage  to  the  tile  arches  and  par- 
titions would  have  been  avoided.  Had  the  partitions  been 
adequately  wedged  so  as  to  render  them  rigid,  and  had  metal 
studs  been  used  at  all  door  openings  to  add  to  this  rigidity,  a 
large  salvage  might  have  been  secured  on  this  portion  of  the  work. 
Had  incombustible  floors  been  used  in  place  of  the  two  thick- 
nesses of  wood  floors  employed,  the  combustible  material  and 
hence  the  severity  of  the  fire  would  have  been  greatly  reduced. 

Home  Buildings:  First  Fire.  —  For  several  years  after 
1892,  —  the  date  of  the  Chicago  Athletic  Club  Building  fire  — 
few  fires  of  prominence  occurred  in  any  so-called  fire-resisting 
buildings,  but  in  1897  both  popular  and  scientific  interest  were 
again  directed  to  the  question  of  fire-resisting  construction 
through  the  now  well-known  Pittsburgh  fire  of  that  year.  This 
was  the  first,  and  the  more  generally  known  fire  in  the  Home 
buildings,  in  Pittsburgh.  The  fire  occurred  May  3,  1897,  en- 
tailing a  loss  of  about  $2,500,000,  the  loss  including  the  complete 
destruction  of  the  non-fire-resisting  building  in  which  the  fire 
originated,  and  the  partial  destruction  of  three  other  buildings, 
to  which  the  fire  was  communicated  externally,  all  of  which  were 
considered  to  be  of  thorough  fire-resisting  design.  The  result, 
therefore,  constituted  the  most  important  test  of  fire-resisting 
methods  which  had  occurred  up  to  that  time,  and  as  each  of  the 
three  buildings  damaged  was  of  an  essentially  different  construc- 
tion from  the  others,  the  comparison  of  materials  and  methods 
exhibited  in  this  instance  have  afforded  very  instructive  interest. 

Description  of  Fire.  —  The  fire  originated  in  a  large  building 
of  the  Jenkins  Wholesale  Grocery  Company,  running  the  full 
depth  of  the  block  from  Liberty  avenue  to  Penn  avenue;  but 
as  this  was  a  non-fire-resisting  structure,  largely  stocked  with 
paints,  oils,  and  inflammable  merchandise,  the  destruction  of  this 
building  is  of  no  particular  interest,  except  to  point  the  moral  of 
how  dangerous  such  a  risk  may  be  to  adjoining  or  nearby  struc- 
tures. For,  upon  the  falling  of  the  walls  of  the  wooden  con- 
struction Jenkins  building,  the  flames  quickly  leaped  across 


138         FIRE   PREVENTION   AND   FIRE   PROTECTION 

Penn  avenue,  destroying  several  pieces  of  the  fire  department's 
apparatus  and  attacking  simultaneously  the  unprotected  fronts 
of  the  Home  Store  Building  and  the  Home  Office  Building. 

It  is  these  two  buildings,  and  also  the  Methodist  Building,  a 
few  doors  to  one  side  of  the  Jenkins  building,  which  are  of  par- 
ticular interest  from  a  fire-resisting  standpoint;,  but,  as  detailed 
descriptions  of  each  are  beyond  the  limits  of  any  condensed 
treatment,  attention  will  be  limited  to  evident  defects  in  design 
or  construction  —  in  short,  to  the  lessons  to  be  derived  from 
this  fire  test. 

The  Home  Store  Building,*  built  in  1893,  was  a  six-story 
and  basement  building  of  about  120  feet  frontage  by  180  feet 
deep  on  Fifth  street.  The  interior  was  entirely  open  and  undi- 
vided, and  while  undivided  areas  of  20,000  square  feet  may  not 
be  open  to  serious  objection  when  used  for  store  purposes,  es- 
pecially if  provided  with  ordinary  safeguards  or  preferably  with 
a  sprinkler  system,  still,  there  can  be  no  excuse  from  a  fire-resist- 
ing standpoint  for  introducing  the  open  light  well.  The  Home 
Store  Building  had  an  open  court,  about  22  feet  by  50  feet  in 
size,  extending  through  the  center  of  the  building  from  first 
story  to  roof,  with  an  iron  railing  on  each  floor.  (See  Fig.  6  in 
author's  " Architectural  Engineering.7') 

This  forms  a  very  common  feature  in  retail-store  design,  and 
with  open  stairways  and  open  elevator  shafts,  no  better  means 
of  communicating  fire  from  floor  to  floor  could  possibly  be  de- 
vised. The  vertical  hazard  is  thereby  made  maximum,  and  the 
present  instance  is  no  exception  to  the  usual  resulting  ruin. 

The  interior  framework  of  the  building  consisted  of  24-inch 
box  girders  framed  between  standard  Z-bar  columns,  with  15- 
inch  floor  beams  resting  upon  shelf  angles  attached  to  the  girders. 
The  floor  arches  were  of  9-inch  hard  burned  terra-cotta  blocks, 
side-construction  pattern,  with  webs  about  f-inch  thick.  The 
tops  of  these  arches  were  on  a  line  with  the  tops  of  the  floor 
beams,  the  skewback  blocks  having  been  made  of  a  special  deep 
pattern  so  as  entirely  to  cover  the  sides  of  the  15-inch  beams, 
thus  presenting  a  panelled  effect  to  the  ceilings,  as  shown  in 
Fig.  31.  The  arches  were  covered  with  4  inches  of  cinder  con- 
crete, in  which  were  embedded  nailing  strips,  14-ins.  centers, 
to  receive  the  hard-pine  floors.  The  columns  were  protected 

*  For  photograph  of  the  two  Home  buildings  after  the  fire,  see  Fig.  5  in 
revised  edition  of  the  author's  "Architectural  Engineering." 


FIRES   IN   FIRE-RESISTING   BUILDINGS 


139 


by  2-inch  blocks  of  hard  burned  terra-cotta  with  one  air  space 
and  webs  about  J-inch  thick,  also  shown  in  Fig.  31. 


FIG.  31.  —  Floor  Arches  in  Home  Store  Building. 

Structural  Damage  and  Defects  in  Design.  —  The  column  cover- 
ings generally  remained  intact  but  the  floor  arches  made  a  poorer 
showing.  The  tops  of  the  arches  were  mostly  in  good  condition 
(save  the  cinder  concrete,  which  was  probably  of  poor  material 
when  originally  placed),  but  the  soffits  of  the  arches  were  largely 
broken  away,  thus  leaving  hollow  spaces  in  the  arches  visible 
from  the  rooms  below.  The  skewbacks  and  girder  casings  were 
also  badly  broken  and,  in  general,  the  terra-cotta  work  through- 
out the  building  had  to  be  replaced,  save  a  salvage  of  16f  per 
cent.  A  considerable  portion  of  the  loss,  however,  was  due  to 
the  falling  of  a  water  tank,  as  will  be  explained  later.  The  com- 
parison between  this  showing  of  hard  burned  terra-cotta  and 
the  porous  terra-cotta  used  in  the  Office  Building  is  worthy  of 
especial  note. 

Another  inconsistent  feature  in  this  building  lay  in  the  use 
of  wooden  brackets  or  " lookouts"  for  the  support  of  the  copper 
cornice.  Had  steel  brackets  been  used,  backed  up  by  brickwork, 
there  would  have  been  little  or  no  loss  to  this  portion  of  the  con- 
struction. As  it  was,  the  cornice  was  a  total  loss. 

It  was  the  open  well  or  vertical  hazard,  however,  in  allowing 
or  causing  a  strong  upward  rush  of  flame  and  intense  heat, 
coupled  with  the  inadequate  protection  of  the  roof  members, 
which  finally  was  the  cause  of  the  greater  part  of  the  structural 
damage.  This  resulted  from  the  falling  of  a  large  pressure  tank, 
6  feet  in  diameter  and  25  feet  long,  weighing,  when  filled,  about 
52,000  pounds.  This  tank  was  supported  on  beams  which  were 


140         FIRE   PREVENTION   AND   FIRE    PROTECTION 

in  turn  supported  by  the  unprotected  roof  beams  and  attic 
columns,  and  it  so  happened  that  the  location  was  in  the  very 
place  where  the  most  severe  heat  was  to  be  expected  —  namely, 
over  the  vertical  flue  made  by  the  elevator  shaft. 

The  roof  framing  consisted  of  10-inch  beams,  but  without 
terra-cotta  arches.  Instead,  a  construction  was  used,  presum- 
ably cheaper,  consisting  of  light  tees,  running  at  right  angles  to 
and  over  the  roof  beams,  between  which  tees  were  laid  2-inch 
hollow  book-tile  to  receive  the  asphalt  roof.  Below  the  roof 
was  a  suspended  ceiling  made  of  1-J-inch  solid  terra-cotta  blocks, 
carried  on  light  tees,  12  inches  centers.  Judging  from  the  warped 
and  weakened  condition  of  these  tees  in  other  portions  of  the 
ceiling  it  seemed  evident  that  that  portion  of  the  ceiling  which 
was  adjacent  to  the  elevator  shaft,  and  hence  subjected  to  the 
greatest  heat,  gave  way  early  in  the  progress  of  the  fire,  thus 
exposing  the  roof  beams  and  columns  and  also^the  tank  supports, 
As  a  result  the  tank  crashed  down  through  all  stories  destroying 
in  its  fall  many  columns  and  girders,  and  large  areas  of  the  floor 
construction.  The  appraisers  estimated  that  not  over  5  per 
cent,  of  the  steel  work  would  have  been  damaged  had  it  not  been 
for  this  circumstance.  As  it  was,  the  total  loss  to  the  steel  work 
was  estimated  at  about  $18,530,  or  about  20  per  cent,  of  the  origi- 
nal cost  of  the  structural  steel. 

It  ought  to  be  needless  to  say  that  there  can  be  no  ultimate 
economy  in  such  disregard  of  thorough  fireproofing.  Like  every- 
thing else,  if  fireproofing  is  worth  doing  at  all,  it  is  worth  doing 
well,  and  the  leaving  exposed  of  such  roof  members  is  simply 
inviting  disaster  at  some  critical  time.  There  have  been  many 
instances  to  show  that  suspended  ceilings  of  the  ordinary  light 
construction  are  not  to  be  fully  relied  upon  as  efficient  fireproofing, 
hence  it  is  as  essential  properly  to  fireproof  attic  spaces  and  roofs 
as  any  other  portions  of  the  building.  In  fact,  even  more  essen- 
tial, on  account  of  their  liability  to  be  called  upon  to  endure  the 
most  intense  heat. 

The  Home  Office  Building  was  a  four-story  and  basement 
building,  94  by  136  feet  in  area,  built  in  1894.  The  first  and 
second  stories  were  used  for  store  purposes,  while  the  third  and 
fourth  floors  were  devoted  to  offices. 

The  principal  items  of  interest  in  this  structure  lay  in  the  terra- 
cotta floor  arches  and  the  partitions.  The  floor  arches,  es- 
pecially, form  a  decided  contrast,  both  in  form  and  material 


FIRES    IN    FIRE-RESISTING    BUILDINGS 


141 


to  those  used  in  the  Store  Building,  so  that  this  simultaneous 
test  by  fire  furnishes  an  interesting  and  valuable  comparison. 

The  floors  of  the  Office  Building  were  built  of  9-inch  end-con- 
struction porous  terra-cotta  blocks,  as  shown  in  Fig.  32.  The 
thickness  of  the  terra-cotta  webs  was  about  J  inch,  so  that  these 
arches  were  of  a  comparatively  heavy  porous  tile,  of  the  then 
new  end-construction,  with  special  skewback  blocks,  as  con- 
trasted with  a  somewhat  lighter,  hard-burned  side-construction 
system  in  the  Store  Building.  Both  constructions  were  of  the 


FIG.  32.  —  Floor  Arches  in  Home  Office  Building. 

same  depth  and  each  presented  a  paneled  ceiling  effect,  so  that 
any  differences  which  were  made  apparent  in  their  ability  to 
withstand  fire  and  water  tests  must  be  found  either  in  the  type 
of  construction  employed  or  in  the  material. 

Structural  Damage  and  Defects.  —  The  fire  damage  to  the 
floor  arches  in  the  Office  Building  was  almost  wholly  confined 
to  the  skewback  blocks,  where  they  protected  those  portions  of 
the  15-inch  beams  which  projected  below  the  soffit  lines  of  the 
arches  proper.  The  bottoms  of  the  flat  arches  were  not  broken 
to  any  such  extent  as  was  the  case  in  the  Store  Building  —  in 
fact,  most  of  the  ceilings  showed  a  perfect,  unbroken  soffit,  save 
considerable  voids  in  the  skewbacks,  along  the  lower  flanges  of 
the  supporting  beams. 

From  the  experience  gained  in  the  Baltimore  conflagration, 
it  is  evident  that  the  type  of  construction  is  not  the  reason  for 
any  decided  difference  in  fire-resisting  qualities.  In  the  Pitts- 
burgh buildings,  the  end-construction  arches  showed  the  better 
results  by  far,  while,  in  the  Baltimore  fire,  one  example  of  end- 
construction  and  one  of  side-construction  were  conspicuous  by 
their  excellent  showing.  The  fire-resisting  differences  must 
therefore,  be  found  in  other  directions. 


142          FIKE   PREVENTION   AND   FIRE   PROTECTION 

The  only  other  difference  between  the  two  Pittsburgh  examples 
lay  in  the  material  —  and  here  is  to  be  found  one  great  cause 
for  variations  in  fire-resistance.  The  Store  Building  had  floor 
arches  of  hard-burned  material,  about  f-inch  thick  webs,  and 
the  results  were  poor.  The  arch  material  used  in  the  Office 
Building  was  porous  with  webs  about  f  inch  thick,  and  the 
results  were  good.  And  upon  investigating  the  material  em- 
ployed in  the  various  terra-cotta  floors  in  the  Baltimore  build- 
ings (see  Chapter  XVII),  it  will  be  found  that  the  excellence  of 
the  results  is  very  largely  a  matter  of  hard  burned  vs.  porous 
material,  the  notably  good  examples  being  all  of  the  latter 
variety. 

Another  serious  structural  defect  in  the  Home  Office  Building 
was  the  partition  construction.  In  order  to  provide  a  nailing 
strip  for  the  attachment  of  the  wooden  base  boards,  the  terra- 
cotta block  partitions  were  built  upon  a  wood  nailing  strip,  the 
destruction  of  which  allowed  many  of  the  partitions  to  fall. 
Such  a  mistake  was  entirely  unnecessary,  as  porous  material  will 
take  nails  almost  as  well  as  wood.  As  a  natural  consequence,  all 
partitions  had  to  be  rebuilt,  but  the  material  was  practically 
as  good  as  when  originally  installed. 

The  Methodist  Building  was  an  eight-story  office  building 
with  floor  arches  of  the  Metropolitan  system,  composed  of 
Portland  cement  and  furnace-slag  concrete.  These  floors  were 
not  subjected  to  any  real  fire  test,  as  there  was  no  room  in  which 
the  woodwork  was  entirely  consumed,  showing  that  this  building 
did  not  receive  the  severe  heat  and  consequent  test  of  the  other 
two. 

Vanderbilt  Building  Fire.  —  The  fire  which  occurred  in 
the  fifteen-story  skeleton  construction  Vanderbilt  Building  in 
New  York  City  on  February  11,  1898,  was  one  of  the  first  serious 
fires  in  a  modern  high  building  to  show  the  imperative  need  of 
precautionary  or  protective  adjuncts  necessary  to  insure  the 
proper  efficiency  of  a  framework  of  incombustible  construction. 
The  critics  of  the  science  of  fire-resistance  during  past  years 
have  particularly  emphasized  the  necessity  of  incombustible  or 
fire-resisting  construction,  and,  as  the  writer  has  pointed  out 
elsewhere,  public  opinion  was  gradually  led  to  expect  little  short 
of  absolute  perfection,  or  immunity  from  all  fire  loss,  provided 
only  the  structure  were  pronounced  of  "  fireproof  construction." 
The  building  of  a  steel  frame,  surrounded  by  brick  walls  and  pro- 


FIRES   IN   FIRE-RESISTING   BUILDINGS  143 

tected  by  terra-cotta  floors  and  column  coverings,  was,  popu- 
larly, at  least,  looked  upon  as  the  consummation  devoutly  to 
be  wished  for  in  building  construction,  while  protective  or  pre- 
cautionary measures  to  aid  the  fire-resisting  materials  in  endur- 
ing any  reasonable  test  put  upon  them,  were,  if  considered  at 
all,  generally  looked  upon  as  superfluous  and  an  unnecessary 
expense.  The  fire  in  the  Vanderbilt  Building  served  to  make 
plain  the  necessity  for  certain  protective  features,  applicable  to 
all  fire-resisting  buildings,  while  the  still  more  serious  fire  in  the 
Home  Life  Insurance  Building  in  New  York,  later  in  the  same 
year,  called  particular  attention  to  such  needs  in  very  high 
buildings. 

The  damage  to  the  Vanderbilt  Building  was  caused  through 
the  burning  of  the  Nassau  Chambers,  an  adjoining  seven-story 
non-fire-resisting  building.  It  was,  therefore,  an  exposure  fire, 
as  one  wing  of  the  latter  building  was  only  40  feet  away  from 
one  wall  of  the  Vanderbilt  Building,  which  had  nine  windows  on 
each  floor  facing  the  fire.  All  of  these  windows  were  provided 
with  iron  shutters,  but  as  none  of  them  was  closed,  the  flames 
from  the  burning  building  naturally  broke  in  the  windows,  and 
the  adjacent  offices  were  soon  gutted.  The  damage  was  confined 
to  the  woodwork,  plastering,  and  to  the  combustible  contents 
of  the  offices,  as  the  structure  was  of  incombustible  construc- 
tion. And  with  this,  the  owners  evidently  rested  content, 
taking  little  apparent  account  of  the  internal  and  external  dan- 
gers constantly  threatening  most  of  our  buildings,  of  however 
good  construction.  In  large  cities  especially,  even  the  best  of 
buildings  are  often  surrounded  by  fire  risks  of  the  worst  possible 
type,  and  these  hazardous  elements  demand  more  precaution  than 
mere  incombustible  construction. 

The  windows  looking  out  upon  the  exposure  created  by  the 
Nassau  Chambers  non-fire-resisting  building  were,  it  is  true, 
provided  with  fire-resisting  shutters,  but  as  they  were  not  closed 
at  the  time  of  the  fire  and  possibly  not  since  the  completion  of 
the  building,  they  might  as  well  never  have  existed.  The  fact 
that  such  shutters  were  in  place,  but  unclosed,  was  a  matter  of 
carelessness  only,  and  more  open  to  criticism  than  their  entire 
absence  would  have  been. 

But  this  was  not  the  only  instance  of  a  short-sighted  policy 
in  regard  to  adequate  fire  protection  in  the  Vanderbilt  Building, 
the  fire  .department  attempted  to  cope  with  the  fire  en- 


144         FIRE    PREVENTION    AND    FIRE    PROTECTION 

veloping  the  upper  floors  it  was  discovered  that  the  building 
was  provided  with  neither  standpipes  nor  hose-reels,  and  the 
firemen  were,  therefore,  obliged  to  connect  their  hose  to  street 
hydrants,  and  face  the  task  of  carrying  continuous  lines  of  hose 
up  fourteen  flights  of  a  narrow  and  crooked  stairway.  This 
feat  would  be  a  difficult  task  at  any  time,  under  even  the  best 
conditions;  but  with  a  smoke-filled  and  poorly  arranged  stair 
well  the  task  became  well-nigh  impossible,  and  in  several  cases 
the  firemen  were  overcome  by  smoke  and  by  exhaustion. 

Fortunately,  great  improvements  have  been  made  during  the 
last  few  years  in  the  matter  of  providing  adequate  standpipes 
with  hose-reels  at  each  and  every  floor,  but,  as  in  the  matter 
of  the  unclosed  shutters  on  the  Vanderbilt  Building,  even  these 
most  necessary  adjuncts  are  very  apt  to  be  carelessly  installed 
and  improperly  maintained,  as  is  pointed  out  in  detail  in 
Chapter  XXXIV. 

The  lessons  to  be  learned  from  this  fire  are,  briefly  —  that 
incombustible  construction  should  be  supplemented  by  adequate 
protection  against  external  exposure,  by  properly  designed 
stairways,  and  by  hose  connections  at  each  and  every  floor, 
capable  of  instant  operation  at  any  moment.  Without  these 
adjuncts,  "the  tall  office  building,  with  all  its  incombustible 
qualities,  is  clearly  a  worse  structure  in  which  to  fight  fire  than 
an  old-fashioned  wooden  floor  building  only  four  or  five  stories 
high." 

Home  Life  Insurance  Building  Fire.  —  The  fire  which 
occurred  in  this  building  in  1898  has  been  of  especial  interest  and 
value  to  those  interested  in  fire-resisting  methods,  and,  with 
the  possible  exception  of  the  Chicago  Athletic  Club  Building  in 
Chicago,  and  in  the  Home  Buildings  in  Pittsburgh,  this  test  of 
•  modern  methods  has  probably  been  more  frequently  quoted  in 
the  annals  of  fire-resisting  construction  than  many  fires  of 
greater  financial  loss  but  of  less  scientific  interest.  In  fact, 
this  fire  undoubtedly  constituted  the  most  heroic  test  of  fire- 
resisting  methods  as  applied  to  the  modern  "  skyscraper ''  which 
had  transpired  up  to  the  date  of  its  occurrence,  and  while  the 
Paterson,  Baltimore,  and  San  Francisco  conflagrations  have 
served  to  lessen  the  seeming  importance  of  all  previous  experi- 
ences, still,  no  fire  confined  to  a  single  fire-resisting  building  has 
been  productive  of  so  much  discussion,  or  of  such  value  in  its 
effects  upon  later  fire-resisting  design. 


FIRES   IN    FIRE-RESISTING    BUILDINGS 


145 


The  Buildings.  —  On  the  night  of  December  4,  1898,  while 
the  severest  northeast  gale  of  the  year  was  raging,  a  bad  fire 
broke  out  in  the  five-story  building  occupied  by  Rogers,  Peet 
&  Co.,  as  a  clothing  store,  at  the  southwest  corner  of  Broad- 
way and  Warren  street,  New  York  City.  This  was  a  building 
of  old-fashioned  wooden  floor-beam  construction  filled  with 
combustibles,  while  adjoining  it  on  the  south  was  the  modern 
steel-frame  building  of  the  Home  Life  Insurance  Company, 
erected  in  J.893.  This  latter  building  had  a  frontage  of  63  feet 
on  Broadway,  by  a  depth  of  about  104  feet  to  the  west.  It  was 
fifteen  full  stories  in  height  with  a  partial  sixteenth  story  on 
the  roof  at  the  base  of  a  pyramidal  tower  which  reached  to  a 
height  of  260  feet  above  the  curb.  The  front  wall  was  of  white 
marble,  self-supporting,  while  all  other  exterior  walls  were  car- 
ried on  the  steel  frame  which  consisted  of  plate  and  angle  col- 


FIG.  33.  —  Floor  Construction  in  Home  Life  Insurance  Company's  Building. 

umns,  plate  girders  running  transversely  across  the  building, 
and  floor  beams,  spaced  about  four  feet  six  inches  centers,  at- 
tached to  the  girders  and  also  resting  upon  shelf  angles.  The 
floor  arches  were  10-inch  hard  tile,  side-construction.  The  lower 
flanges  of  the  girders,  where  they  projected  through  the  ceil- 
ings, were  protected  by  means  of  terra-cotta  blocks  resting 
on  the  flanges,  and  by  a  wrapping  of  expanded  metal  lath  and 
plaster  around  the  lower  surface  (see  Fig.  33).  The  column 
coverings  consisted  of  2-inch  porous  terra-cotta  blocks,  and  the 
partitions  were  of  4-inch  porous  tile,  the  upper  four  feet  in  the 
corridor  partitions  being  filled  in  with  wood  sash  and  glass  for 
the  transmission  of  light.  In  short,  the  building  was  passably 
well  designed  against  internal  hazard;  it  was  provided  with 
standpipes  and  hose-reels,  and,  had  the  fire  originated  from 
within,  there  can  be  little  doubt  that  it  could  have  been  confined 
the  floor  or  even  to  the  apartment  in  which  it  occurred. 


146          FIRE    PREVENTION    AND    FIRE    PROTECTION 

The  external  or  exposure  hazard,  however,  was  seemingly 
given  less  consideration,  and,  as  both  the  cause  and  the  magni- 
tude of  the  disaster  were  due  to  external  sources,  the  loss  was 
principally  attributable  to  this  neglect. 

Back  of  the  three  passenger  elevators,  which  were  located  at 
about  the  center  of  the  building,  was  an  external  light  court 
about  20  by  24  feet  in  size,  indenting  the  north  wall  adjacent 
to  the  Rogers,  Peet  Building.*  This  court  was  faced  with  white 
enameled  brick.  There  were  two  windows  at  each  floor,  back 
of  the  elevator  shafts,  and  four  windows,  with  narrow  mullions 
between,  on  each  side  of  the  court  at  every  floor.  In  addition 
to  these  court  windows,  there  were  two  windows  in  offices  in 
each  of  the  upper  stories  overlooking  the  roof  of  the  Rogers, 
Peet  Building.  None  of  these  openings  were  provided  with 
shutters  or  fire-resisting  windows  of  any  description. 

The  Fire.  —  For  some  time  after  the  outbreak  of  the  fire,  the 
adjacent  buildings  were  protected  by  the  strenuous  efforts  of 
the  firemen,  and  although  the  flames,  escaping  through  the 
windows  and  roof,  were  blown  directly  against  the  north  walls 
of  the  Home  Building,  still  the  latter  structure  did  not  take  fire 
for  almost  an  hour.  The  firemen  entered  the  Home  Building 
and  with  the  standpipes  at  hand  and  streams  from  fire  engines 
succeeded  in  localizing  the  fire  until  the  roof  of  the  corner  build- 
ing fell  in.  This  caused  a  great  volume  of  flame  to  be  blown 
against  the  north  walls  of  the  Home  Building  and,  drawn  to 
the  open  court  as  to  a  great  chimney,  it  was  not  long  before 
the  glass  in  the  windows  of  the  upper  floors  gave  way  and  fire 
was  quickly  communicated  to  the  interior.  Up  to  the  eighth 
story  the  firemen  were  able  to  work  successfully,  while  above 
that  level  the  pressure  and  volume  of  water  obtainable  with 
their  fire  apparatus  was  insufficient  and  the  intense  heat  drove 
them  from  vantage  grounds  in  the  corridors,  thus  preventing 
the  use  of  streams  from  the  building's  standpipes. 

Structural  Damage.  —  The  greatest  fire  damage  done  was 
from  the  eleventh  floor  up,  being  greatest  in  those  rooms  adjacent 
to  the  court.  From  the  eleventh  floor  down  the  damage  gradu- 
ally decreased,  until  at  the  seventh  floor  it  was  principally  due 
to  smoke  and  water. 

The  principal  structural  injury  to  the  building  consisted  of 

*  For  floor  plan  see  Fig.  18  in  the  author's  "The  Fireproofing  of  Steel 
Buildings." 


FIRES    IN    FIRE-RESISTING    BUILDINGS  147 

the  damage  done  to  the  marble  front.  Portions  of  the  cornice 
and  balcony  and  other  ornamental  marble  work  in  the  upper 
stories  fell  to  the  street,  and  other  parts  were  so  unsafe  as  to 
require  extensive  shoring.  This  front  was  later  rebuilt  above 
the  eighth  floor.  The  side  and  court  walls  stood  the  test  re- 
markably well,  and  the  terra-cotta  arches,  with  some  exceptions, 
required  little  repair;  but  as  the  exceptions  were  directly  due 
to  grave  mistakes  in  the  floor  design,  a  somewhat  more  detailed 
description  of  this  portion  of  the  construction  is  worthy  of 
consideration  as  illustrating  a  lesson. 

In  accordance  with  conditions  imposed  by  the  steel  framing, 
9-inch  floor  beams  were  used  in  the  front  portion  of  the  building 
and  12-inch  beams  in  the  rear  portion,  but  instead  of  using  differ- 
ent depth  terra-cotta  arches,  as  most  certainly  should  have 
been  done,  10-inch  side-construction  arches  were  used  for  all 
cases.  Also  the  wooden  floors,  consisting  of  two  thicknesses 
of  f-inch  flooring,  were  fastened  to  3-  by  4-inch  sleepers  (spaced 
every  16  inches),  which  were  laid  on  top  of  the  beams.  This 
left  open  spaces  of  about  four  inches  and  seven  inches  in  the 
front  and  rear  portions  of  the  building,  respectively,  between 
the  tops  of  the  terra-cotta  arches  and  the  underside  of  the  floor- 
ing, as  shown  in  Fig.  33,  and  although  these  voids  were  supposed 
to  be  divided  at  intervals  by  concrete  stops,  this  construction 
still  left  the  top  flanges  of  the  beams  and  girders  exposed,  when 
the  woodwork  was  consumed.  Over  a  large  part  of  the  building 
above  the  seventh  floor  the  flooring  and  sleepers  were  consumed, 
the  combustion  doubtless  being  greatly  aided  by  these  air  spaces; 
and  that  much  more  serious  damage  did  not  result  can  only  be 
attributed  to  the  limited  height  of  the  exposed  metal.  As  before 
stated,  the  general  condition  of  the  terra-cotta  arches  themselves 
was  satisfactory,  but  the  voids  over  the  arches  were  directly 
responsible  for  several  failures,  the  principal  of  which  occurred 
on  the  tenth  and  fifteenth  floors.  In  the  former  case,  the  failure 
of  the  arch  which  fell  was  due  to  the  breaking  through  of  a  safe, 
doubtless  caused  by  the  burning  of  the  wooden  flooring,  thus 
allowing  the  safe  to  fall  a  height  of  several  inches  through  the 
air  space  and  upon  the  terra-cotta  arch,  shattering  it  exactly  as 
occurred  in  the  Equitable  Building  in  the  Baltimore  fire.  Had 
these  free  spaces  been  filled  with  a  good  quality  of  concrete,  this 
would  have  prevented  the  falling  of  safes,  and  protected  the  top 
flanges  of  the  steel  floor  members. 


148         FIRE    PREVENTION    AND    FIRE    PROTECTION 

Just  how  much  damage  was  done  to  the  partitions  by  fire  and 
water,  or  what  injury  was  done  by  the  firemen  who  knocked 
many  of  them  down  to  get  at  the  flames,  it  would  be  hard  to 
say.  The  burning  of  the  wooden  doors  and  windows  in  the 
partitions  and  their  casings  was  probably  responsible  for  much 
damage;  and  the  common  plan  of  locating  such  partitions  to 
suit  tenants,  placing  them  indiscriminately  over  the  wooden 
floors  after  the  completion  of  the  building  with  insecure  attach- 
ment to  floor  and  ceiling,  adds  instability  (upon  burning  away 
of  floor  boards)  to  what  must  be  admitted  as  being  one  of  the 
weakest  features  of  fire-resisting  methods  —  namely,  block  par- 
titions in  general.  In  the  twelfth  story  some  partitions  made 
of  plaster  on  a  framework  of  small  angle-studs  covered  with 
expanded  metal — the  total  thickness  being  2  inches — remained 
in  position,  though  they  were  badly  distorted.  Their'  insuffi- 
ciency was  amply  demonstrated,  and  had  the  force  of  fire  hose 
been  added  to  the  heat,  the  result  would  undoubtedly  have  been 
still  worse. 

Home  Store  Building:  Second  Fire.  —  By  a  singular 
fatality,  the  Home  Store  Building  in  Pittsburgh,  which  was 
damaged  by  fire  in  May,  1897  (a  description  of  which  has  already 
been  given),  was  seriously  damaged  by  a  second  fire  on  April  9, 
1900;  and  as  two  of  the  vital  defects  in  the  design  and  con- 
struction of  the  original  building  were  retained  in  the  remodeled 
structure,  it  is  not  strange  to  find  that  these  same  features 
largely  contributed  to  the  extensive  loss  which  resulted  from  the 
second  fire. 

It  will  be  remembered  that  the  principal  constructive  features, 
which  were  open  to  condemnation  from  a  fire-resisting  stand- 
point in  the  original  design,  were  the  presence  of  unprotected 
vertical  openings  in  the  form  of  stairways,  elevator  wells,  and  a 
large  interior  light  well  extending  through  all  stories;  and  the 
unprotected  character  of  the  roof  beams  and  columns.  The 
building  was  reconstructed  after  the  first  fire,  and,  as  the  open 
interior  light  well  is  a  feature  apparently  insisted  upon  by. the 
owners  of  department  or  large  retail  stores  the  world  over, 
possibly  it  was  too  much  to  expect  that  this  attractive  means  of 
lighting  all  floors  and  adding  a  seeming  extensiveness  to  the 
structure  should  have  been  abandoned  and  closed  up,  in  spite 
of  the  fact  that  its  presence  in  the  first  fire  contributed  largely 
to  the  extent  of  the  loss  sustained.  But  that  the  great  error  of 


FIRES   IN   FIRE-RESISTING   BUILDINGS  149 

leaving  the  roof  construction  unprotected  should  have  been 
repeated  in  view  of  the  tremendous  damage,  which  was  pre- 
viously due  to  this  very  cause  through  the  falling  of  the  water 
tank  after  the  collapse  of  the  roof  beams  and  columns,  seems 
well-nigh  incredible.  Yet  this  was  the  case,  and  the  first  col- 
lapse of  the  roof  was  duplicated  in  the  second  fire,  but  without 
the  added  element  of  the  roof  tank. 

The  second  fire  is  supposed  to  have  originated  on  the  fifth 
floor,  and  the  results  included  the  general  burning  out  of  every- 
thing combustible  on  the  fourth,  fifth,  and  sixth  floors.  When 
about  under  control  in  these  upper  stories,  it  was  found  that  the 
fire  had  worked  down  into  the  basement,  presumably,  by  means 
of  a  vertical  shaft  or  dumb  waiter.  The  first  story  was  also 
burned  in  part,  due  to  blazing  embers  falling  within  the  light 
well.  The  second  and  third  stories  suffered  damage  mainly 
through  smoke  and  water. 

The  condition  of  the  terra-cotta  fireproofing  (of  porous  variety) 
was  most  satisfactory.  The  roof  damage  was  far  more  serious. 
As  in  the  first  construction,  the  roof  was  made  of  tee  irons,  rest- 
ing upon  the  roof  beams,  and  carrying  17-inch  "book"  tiles  of 
terra-cotta  3  inches  thick.  All  of  this  metal  work  was  unpro- 
tected, save  by  a  false  ceiling  several  feet  below  the  roof.  This 
virtually  made  an  attic  space.  The  suspended  ceiling  was  made 
of  expanded  metal  and  plaster,  applied  on  l^-inch  angle  irons 
hung  from  the  roof  beams.  This  ceiling  quickly  "wilted" 
from  the  intense  heat  of  the  fire  raging  in  the  sixth  story,  thus 
allowing  the  heat  to  reach  the  roof  beams  and  the  upper  portions 
of  the  top-story  columns.  The  result  was  the  utter  collapse  of 
about  one-half  of  the  roof  construction.  It  was  greatly  to  the 
credit  of  the  terra-cotta  arches  in  the  sixth  floor  that  they 
successfully  withstood  the  precipitation  of  this  great  weight  of 
debris  upon  them. 

This  fire  shows  that  it  is  possible  to  erect  a  building  which 
can  be  pretty  weir  gutted  by  flames  and  yet  suffer  comparatively 
little  itself.  It  demonstrates  that  fireproofing  has  reached  a 
stage  justifying  reliance  upon  its  efficacy,  and  warranting  the 
belief  that  in  such  an  ordinarily  severe  fire  as  that  described, 
the  loss  is  to  be  attributed  to  the  design  of  the  building,  for  which 
the  owners  are  undoubtedly  responsible,  and  not  to  defective 
fire-resisting  construction.* 

*  See  The  Engineering  Record,  April  14,  1900. 


150         FIRE   PREVENTION   AND   FIRE   PROTECTION 

The  Paterson  (N.  J.)  Conflagration.  —  The  importance  of 
this  test  of  fire-resisting  buildings  which  were  practically  sur- 
rounded by  the  very  worst  character  of  combustible  structures, 
has,  of  cdurse,  been  largely  dimmed  through  the  magnitude  of 
the  more  recent,  more  extensive,  and  more  conclusive  disasters 
at  Baltimore  and  San  Francisco  Nevertheless,  certain  con- 
spicuous facts  stand  out  in  the  Paterson  fire,  not  only  of  great 
value  in  themselves,  but  of  added  value  now  in  confirming  or 
disproving  certain  deductions  which  have  been  drawn  from  the 
Baltimore  and  San  Francisco  experiences. 

The  Paterson  conflagration  occurred  on  February  8,  1902, 
starting  in  the  car  sheds  and  repair  shops  of  the  Paterson  Rail- 
way Company  at  midnight,  while  the  wind  was  blowing  sixty 
miles  an  hour.  The  fire  raged  for  nearly  twenty-four  hours, 
destroying  approximately  ten  city  blocks  in  the  heart  of  the 
business  area,  besides  an  area  almost  as  large  within  the  resi- 
dential district,  where  the  conflagration  was  communicated  by 
means  of  flying  sparks  and  embers  nearly  a  half-mile  distant 
from  the  first  fire.  The  total  loss  was  estimated  at  $5,800,000. 

The  general  construction  of  the  burned  mercantile  district 
was  of  the  dangerous,  non-fire-resisting  character,  consisting 
mainly  of  old  brick  buildings  with  frame  structures  scattered 
between,  and  here  and  there  an  isolated  structure  of  approved 
fire-resisting  design.  The  city  building  laws  had  long  been  a 
dead  letter,  and  it  was  no  difficult  matter  to  secure  permission 
to  erect  almost  any  kind  of  building  at  almost  any  location. 
The  effect  which  one  adequate  fire-resisting  structure  may 
have  in  preventing  the  spread  of  a  conflagration  beyond,  was 
well  shown  in  the  Paterson  Savings  Institution  Building.  This 
was  a  five-story  and  basement  building  at  the  corner  of  Main 
and  Market  streets,  and  the  spread  of  the  conflagration  to  the 
south  and  west  was  completely  checked  by  the  fire  resistance 
offered  by  this  structure.  The  principal  resistance  to  the  prog- 
ress of  the  fire  lay  in  the  blank  brick  walls  on  the  conflagration 
side,  but  the  fire-resisting  floors  made  of  the  Guastavino  system 
also  served  to  protect  the  interior,  and  hence  to  save  the  building 
from  utter  ruin.  As  it  was,  the  contents  of  the  upper  two 
stories  were  entirely  consumed,  but  structurally  the  building 
was  without  serious  damage  —  a  splendid  tribute  to  fire-re- 
sisting construction. 

City   Hall   Building.  —  The   most   interesting   test   afforded 


FIRES   IN   FIRE-RESISTING   BUILDINGS  151 

by  this  fire  was  the  beautiful  new  City  Hall  Building.  This 
was  of  four  stories  and  tower,  about  75  feet  by  150  feet  in  area, 
with  Indiana  limestone  fagades  and  floors  of  terra-cotta  arches. 
Three  sides  of  this  structure  were  exposed  to  the  conflagration 
at  distances  ranging  from  60  feet  to  150  feet.  Across  one  60- 
foot  street  was  an  entire  block  made  up  of  combustible  store 
buildings  which  were  all  on  fire  at  one  and  the  same  time,  the 
nearest  and  also  the  most  dangerous  of  which  was  the  Romaine 
Office  Building.  A  solid  mass  of  flame  from  this  structure  was 
blown  against  the  west  wall  of  the  City  Hall,  while  the  north 
and  south  sides  were  also  subjected  to  extreme  heat.  The  result 
included  the  entire  destruction  of  the  combustible  contents, 
including  all  of  the  wood  trim,  the  furnishings,  and  the  city 
records  —  except  in  one  room  where,  strange  to  say,  even  the 
carpets  and  furniture  were  untouched.  The  stone  ashlar  was 
largely  disintegrated,  especially  at  corners  and  window  soffits, 
but  the  floor  arches  remained  intact  and  the  integrity  of  the 
tower  was  unimpaired. 

But  the  principal  interest  in  the  test  of  this  building  seems  to 
lie  not  in  the  structural  damage  done  to  the  City  Hall  itself, 
as  the  result  only  furnishes  another  example  of  the  fact  that  bad 
losses  must  be  expected  in  even  the  best  of  fire-resisting  build- 
ings which  are  exposed  through  unprotected  openings,  —  and 
not  in  the  damage  done  the  limestone  ashlar,  as  this  was  a 
result  most  certainly  to  be  expected,  —  but  rather  in  the  fact, 
as  in  the  case  of  the  Paterson  Savings  Institution  Building,  that 
a  fire-resisting  building  may  be  completely  gutted  in  itself,  and 
still  afford  effective  protection  to  structures  beyond.  Speaking 
on  this  point,  the  report  on  this  fire  issued  by  the  Continental 
Fire  Insurance  Company  states  as  follows:  "The  City  Hall, 
which  was  surrounded  on  all  sides  by  unprotected  openings, 
also  affords  a  good  example  of  the  fact  that  a  fireproof  building 
is  not  an  exposure  to  another  fireproof  building,  under  ordinary 
conditions,  and  in  this  case  it  acted  as  a  break  and  prevented 
any  damage  of  importance  being  done  to  the  fireproof  Second 
National  Bank  Building,  only  50  feet  distant."  It  is  interest- 
ing to  note  that  this  deduction  was  verified  in  the  Baltimore 
conflagration  through  the  manner  in  which  the  fire-resisting 
character  of  the  Baltimore  " Herald,"  Calvert,  and  Equitable 
Buildings  undoubtedly  saved  the  magnificent  Court  House,  which 
would  surely  have  been  destroyed  (and  beyond  that  no  one  can 


152         FIRE    PREVENTION    AND    FIRE    PROTECTION 

even  estimate  how  many  more  blocks)  had  these  three  build- 
ings in  the  path  of  the  flames  been  of  a  combustible  and  hence 
collapsible  character. 

Lessons  of  Fire.  —  The  before-mentioned  report  on  this  fire 
issued  by  the  Continental  Fire  Insurance  Company,  deduces 
the  following  conclusions: 

First:  The  efficiency  of  a  fire-resisting  building  as  a  fire  stop, 
even  though  its  interior  may  be  gutted  on  account  of  absence 
of  fire  shutters. 

Second:  The  efficiency  of  blank  walls  as  fire  stops,  as  com- 
pared with  the  ordinary  street. 

Third:  The  extreme  danger  of  a  conflagration  when  a  num- 
ber of  buildings  are  exposed  by  a  paralleling  risk  in  the  rear, 
which  is  likely  to  start  fires  simultaneously  in  all. 

Fourth:  The  danger  of  several  fires  in  different  parts  of  a 
city  at  once  from  flying  embers  falling  on  wooden  roofs. 

Fifth:  The  necessity  of  efficient  assistants  to  take  the  place 
of  the  chief  of  the  fire  department  in  case  of  his  disability. 

Roosevelt  Building  Fire.  —  The  fatal  fire  which  occurred 
in  this  building  in  New  York  City,  February  26,  1903,  empha- 
sized two  lessons  which  will  bear  repeating,  and  called  particular 
attention  to  a  common  defect  in  stair  construction  which  resulted 
in  a  change  of  building  laws  on  this  subject  in  New  York  and 
elsewhere. 

This  was  an  eight-story  building,  erected  in  1893,  and  supposed 
to  be  thoroughly  fire-resisting,  but  the  destruction  by  fire  of  the 
upper  stories  developed  the  fact  that  unprotected  cast-iron 
columns,  in  combination  with  steel  floor  beams  and  segmental 
terra-cotta  arches,  had  been  considered  efficient  construction, 
else  why  should  the  expense  of  fire-resisting  floor  arches  have 
been  justified,  if  unprotected  cast-iron  columns  had  not  been 
considered  equally  fire-resisting?  Of  eighteen  7-inch  columns 
supporting  the  roof,  three  only  remained  in  perfect  condition. 
The  others  were  either  broken  or  warped. 

Another  important  lesson  was  taught  by  this  fire  through  the 
enormous  damage  done  by  water  to  the  clothing  stock  in  the 
lower  stories  of  the  building.  TJiis  point  is  generally  over- 
looked by  both  owners  and  architects,  but  in  buildings  contain- 
ing large  or  valuable  stocks  or  merchandise,  the  ordinary  detail 
of  wood  floor  upon  some  form  of  fire-resisting  floor  arch  is  not 
capable  of  properly  protecting  the  stories  which  may  be  located 


FIRES    IN    FIRE-RESISTING    BUILDINGS  153 

below  the  seat  of  the  fire.  Waterproofing  below  wood  floors, 
or  some  type  of  fire-resisting  and  waterproof  flooring  such  as 
terrazzo,  monolith,  or  cement,  laid  to  pitch  toward  scuppers  in 
the  outside  walls,  would  entirely  obviate  this  possible  cause  of 
often  great  financial  loss. 

The  most  regrettable  feature  of  this  fire  lay  in  the  death  of 
one  of  the  Fire  Department  captains,  who  stepped  through  a 
marble  stair  platform  which  he  doubtless  considered  firm  and 
safe,  but  which  had  been  cracked  or  completely  broken  either 
by  the  disintegrating  effects  of  the  heat  or  by  the  precipitation 
upon  it  of  debris  from  above.  The  platforms  of  successive  stories 
below  also  failed  under  his  fall.  Had  this  building  been  erected 
since  the  enforcement  of  the  present  Greater  New  York  building 
law,  this  could  not  have  occurred,  as  sub-treads  of  iron  are  now 
required  under  all  slate  or  marble  stair  treads  and  platforms. 
The  wisdom  of  this  requirement  was  also  well  attested  in  the 
various  experiences  gained  at  Baltimore,  where  slate  and  marble 
stair  treads,  and  especially  larger  platforms,  were  everywhere 
found  to  be  dangerously  cracked,  if  not  gone  altogether. 

Fire-resisting  stair  construction  is  considered  in  detail  in 
Chapter  XV. 

Iroquois  Theater  Fire.  —  It  seems  rather  a  paradox  to  say 
that  the  greatest  loss  of  life  which  has  ever  been  recorded  in 
a  theater  in  the  United  States  occurred  in  a  theater  building 
which  was  " fire-resisting''  according  to  the  interpretation  of  a 
fairly  satisfactory  code  of  building  laws.  Indeed,  the  Iroquois 
Theater  fire  was  not  only  memorable  from  the  great  loss  of  life 
involved,  but  also  in  that  it  was  the  first  serious  fire  which  has 
broken  out  in  a  theater  (during  a  performance)  since  the  intro- 
duction of  scientific  fire-resisting  methods. 

This  disaster  serves  as  another  lamentable  but  striking  ex- 
ample of  the  truth  that  "  fire-protected "  and  "  fire-resisting " 
construction  are  by  no  means  synonymous,  but  that  many 
fire-protective  devices  and  appliances  are  absolutely  necessary 
to  insure  the  integrity  of  a  fire-resisting  construction,  or  to 
insure  the  safety  of  those  who  rely  on  such  construction  for  the 
safety  of  their  lives. 

The  Iroquois  Theater  Building  in  Chicago  had  been  opened 
to  the  public  but  a  few  days,  when,  during  a  matinee  spectacular 
performance  on  December  30,  1903,  the  fire  occurred  which 
resulted  in  the  loss  of  566  lives,  mostly  women  and  children. 


154         FIRE   PREVENTION   AND   FIRE   PROTECTION 

The  terrible  fatality  among  the  audience  may  be  judged  from 
the  fact  that  the  total  audience  comprised  about  1800  people, 
698  in  seats  on  the  lower  floor,  421  in  the  balcony,  447  in  the 


Skylight 


Ventilator 


Eire  Escapes 
FIG.  34.  —  Cross  Section  and  Plan  of  Iroquois  Theater,  Chicago. 

gallery,  40  in  the  boxes,  besides  about  200  people  standing  in 
open  spaces,  and  even  sitting  on  the  steps  of  the  aisles  in  the 
very  steep  gallery. 

The  Fire  is  said  to  have  started  on  the  stage  from  the  con- 
tact of  a  border  scene  or  a  hanging  drapery  with  an  electric  arc 


FIRES   IN   FIRE-RESISTING   BUILDINGS  155 

light,  but,  whatever  the  cause,  the  rush  of  flame,  smoke,  and 
gases,  was  both  very  sudden  and  deadly,  even  while  doing 
little  structural  damage  to  the  auditorium,  as  is  evidenced 
by  the  fact  that  draperies  in  one  of  the  boxes  were  practically 
unharmed,  while  the  upholstering  of  the  parquet  seats  was 
only  consumed  in  the  first  eight  rows  from  the  stage.  In  less 
than  thirty  minutes  the  fire  had  been  extinguished,  but  the 
faults  of  omission  and  commission  had  been  so  many  and  so 
glaring  that  it  seems  well-nigh  impossible  that  any  amusemen^ 
place,  where  so  many  people  are  provided  for,  could  have  been 
opened  to  the  public  in  such  a  condition.  The  result  con- 
stituted the  saddest  and  the  most  forcible  demonstration  we 
have  yet  had  save,  possibly,  the  Asch  Building  fire,  of  the 
folly  of  relying  upon  fire-resisting  construction  per  se  for  safety 
of  human  life.  It  demonstrated  that  construction  bears  little 
relation  to  the  possible  loss  of  life,  unless  the  construction  is 
supplemented  by  fire-preventive  design  and  precautions,  and 
by  fire-protective  appliances  and  devices.  This  is  not  to  say 
that  the  construction  should  be  anything  but  the  most  ap- 
proved fire-resisting  type,  but  that,  in  this  class  of  building 
more  than  in  any  other,  safeguards  of  proper  design  and 
equipment  must  supplement  to  the  fullest  degree  even  the  best 
construction. 

Hazards  and  Defects.  —  The  greatest  fire  dangers  in  such 
buildings  as  theaters,  schools,  and  churches,  consist  in  panic, 
suffocation  from  smoke  and  gases,  and  being  crushed  or  trampled 
to  death  at  improper  exits.  All  of  these  things  happened  in 
the  Iroquois  Theater,  and  all  were  aided  and  abetted  by  the 
conditions  which  existed. 

First,  as  to  panic.  People  were  standing  or  sitting  in  the 
various  aisles  in  great  numbers;  there  was  no  wide  aisle  back 
of  the  parquet  seats,  hence  no  lateral  movement  was  possible 
except  over  the  seats,  and  the  auditorium  was  in  darkness. 

The  arrangement  of  stairways  was  defective  in  that  persons 
coming  down  the  stairs  from  the  upper  door  of  the  balcony  had 
to  pass  the  lower  door  in  order  to  reach  the  next  flight  of  stairs, 
and  through  this  door  the  fire  was  pouring  and  people  were 
rushing.  Had  the  upper  gallery  extended  to  a  separate  stair- 
way to  the  street  (as  might  naturally  be  inferred  by  people  com- 
ing out  of  the  theater)  instead  of  fto  a  private  office  with  locked 
door,  many  lives  would  in  all  probability  have  been  saved.  It 
is  said  that  no  less  than  thirty  bodies  were  found  in  the  trap 
formed  by  the  locked  door  to  the  manager's  office. 


156        FIRE    PREVENTION    AND   FIRE   PROTECTION 

Second,  as  to  suffocation  and  burning.  The  most  effectual 
safeguards  known  to  theater  construction,  viz.,  roof  vents  over 
the  stage,  and  fire  curtain  between  the  stage  and  auditorium, 
were  both  inoperative.  The  stage  was  provided  with  a  vent 
and  two  skylights,  as  shown  by  the  cross-section  of  theater  in 
Fig.  34,  all  intended  to  be  automatic  in  action,  so  as  to  open  or 
break  in  case  of  fire;  but  all  were  uncompleted  and  hence  in- 
operative, the  skylights  being  nailed  up  by  outside  timbers. 


FIG.   35.  —  Map  of  Baltimore  Conflagration. 


Also,  the  asbestos  fire  curtain  was  rendered  useless  by  an  inter- 
fering swinging  bracket  (used  to  carry  electric  lights  for  scenic 
effects) ,  which  so  swung  out  from  the  stage  side  of  the  proscenium 
wall  as  to  block  the  curtain  when  part  way  down.  This  in  spite 
of  the  fact  that  the  identical  thing  had  happened  a  week  previous, 
during  a  slight  fire  at  a  rehearsal. 

Third,  improper  exits.  The  theater  is  said  to  have  had  27 
exit  doors,  inadequately  marked,  as  no  lights  were  visible  after 
the  outbreak  of  the  fire.  Nearly  all  doors  had  opening  devices 
or  levers  which  operated  top  and  bottom  bolts,  but  many  doors 


FIRES   IN   FIRE-RESISTING   BUILDINGS  157 

were  frozen  fast  by  snow  and  ice  on  the  outside  fire  escapes,  etc. 
All  inner  doors  opened  inward. 

More  details  in  connection  with  this  building  and  fire  are 
given  in  Chapter  XXII. 

The  Baltimore  Conflagration.  —  The  conflagration  which 
swept  Baltimore  on  February  7  and  8,  1904,  constituted  the 
most  momentous  test  ever  applied  to  fire-resisting  construction. 
The  great  Chicago  fire  of  1871  involved  a  monetary  loss  which 
exceeded  that  caused  by  the  Baltimore  fire,  but  fire-resisting 
construction  was  then  unknown,  and  only  came  into  being  in 
this  country  as  a  direct  result  of  that  experience.  The  San 
Francisco  conflagration  of  1906,  which  will  be  described  later, 
also  involved  a  greater  loss  than  that  at  Baltimore,  but  the 
doubt  which  will  always  exist  as  to  the  relative  amount  of 
damage  done  at  San  Francisco  by  earthquake  or  fire,  ranks  that 
conflagration  as  second  to  the  Baltimore  experience  as  a  positive 
test  of  fire-resistive  methods  and  materials. 

Extent  of  Fire.  —  A  proper  conception  of  the  extent  of  the 
fire  and  its  irresistible  fury  is  necessary  before  the  effects  can 
be  properly  judged. 

The  devastated  area  covered  about  140  acres  or  80  city  blocks. 
To  appreciate  properly  the  area  which  these  figures  indicate  it 
is  necessary,  for  those  at  least  who  are  not  familiar  with  the 
business  district  of  Baltimore,  to  compare  the  burned  territory 
with  cities  with  which  one  is  entirely  accustomed.  A  similar 
area  in  New  York  City  would  include  that  entire  portion  of  the 
city  lying  below  Chambers  street,  or  below  City  Hall  Park; 
while  in  Boston  a  similar  comparison  would  include  the  area 
between  Adams  Square  and  West  Street  in  one  direction,  and 
between  Tremont  street  and  Atlantic  avenue  in  the  other. 
And  as  both  of  these  areas  include  most  of  the  finest  and  most 
costly  business  buildings  in  those  cities,  so  did  the  Baltimore 
fire  sweep  the  finest  section  of  the  city  before  it,  so  that  few 
modern  buildings  of  any  prominence  were  left,  save  the  Court 
House,  the  City  Hall,  and  Postoffice.  About  2500  buildings 
were  destroyed,  including  office  and  bank  buildings,  retail  and 
wholesale  stores,  warehouses,  markets,  wharves,  and  lumber 
yards,  involving  a  loss  of  about  $40,000,000. 

Before  considering  any  of  the  buildings  in  detail,  it  is  first 
necessary,  as  before  stated,  to  secure  as  adequate  an  idea  as 
possible  of  the  tremendous  proportions  of  the  conflagration  up 


158         FIRE   PREVENTION   AND   FIRE   PROTECTION 

to  the  time  the  distinctly  fire-resisting  buildings  were  attacked. 
Referring  to  the  map  shown  in  Fig.  35,  the  fire  originated  at 
about  11  A.M.  on  Sunday,  February  7,  in  the  Hurst  dry-goods 
store  on  Liberty  street,  the  western  boundary  of  the  fire  area; 
and  by  7  or  8  P.M.  it  had  spread  to  the  office-building  district 
as  far  east  as  Calvert  street  and  as  far  north  as  Fayette  street. 
By  this  time,  also,  the  authorities  had  resorted  to  the  use  of 
dynamite  in  an  attempt  to  demolish  buildings  in  the  path  of 
the  fire,  so  as  to  form  open  spaces  from  which  the  flames  could 
be  fought,  or  across  which  the  fire  could  not  extend.  But  on 
account  of  various  delays  owing  to  unfamiliarity  with  the  use 
of  dynamite,  several  buildings  were  not  blown  up  until  com- 
pletely wrapped  in  flame,  and  to  this  cause  the  owners  of  several 
buildings,  notably  of  the  Union  Trust  Company's  Building  at 
Fayette  and  St.  Paul  streets,  attributed  the  great  loss  to  their 
structures.  The  explosion  of  the  burning  buildings  only  served 
to  spread  or  scatter  the  flame  and  to  increase  its  intensity. 

Intensity  of  Fire.  —  By  the  time  the  fire  reached  the  large 
office  buildings,  near  the  center  of  the  northern  boundary,  the 
area  in  flames  consisted  of  twenty  or  more  blocks  of  non-fire- 
proof buildings  and,  before  one  is  too  critical  as  to  the  behavior 
of  the  supposedly  fire-resisting  buildings,  it  is  well  to  consider 
what  a  tremendous  heat  must  have  been  driven  with  the  flames 
—  an  intensity  of  heat  which  no  construction  could  have  been 
expected  wholly  to  withstand.  In  all  of  the  high,  buildings 
which  remained,  there  was  every  evidence  of  this  destructive 
heat.  In  the  critical  examination  made  by  the  writer  of  almost 
every  one  of  the  fire-resisting  buildings,  hardly  a  vestige  of 
woodwork  or  combustible  matter  of  any  kind  was  to  be  seen. 
Of  wooden  nailing  strips  which  had  been  built  into  the  brick 
walls,  the  nails  alone  remained,  projecting  from  the  slots  in  the 
brickwork,  but  scarcely  even  ashes  of  the  woodwork  were  to 
be  seen  even  in  the  deepest  portions  of  the  grooves.  Wood 
hand  rails  on  stair  balustrades  were  completely  gone,  marble 
floors  and  wainscots  were  cracked  or  reduced  to  a  powdery 
mass;  ornamental  wrought-iron  and  bronze  work  was  wrecked 
and  almost  melted,  while  glass  windows  and  globes  had  melted 
and  run  into  grotesque  shapes.  One  of  the  solid  marble  columns 
in  the  entrance  rotunda  of  the  Calvert  Building  is  shown  in 
Fig.  36.  "It  is  estimated  that  the  temperature  of  the  fire  was 
rarely  much  in  excess  of  2200°  F.,  although  in  some  spots  it 


FIRES   IN   FIRE-RESISTING   BUILDINGS  159 


FIG.  36.  —  Entrance  Rotunda  of  Calvert  Building,  Baltimore  Fire. 


160  FIRE    PREVENTION    AND    FIRE    PROTECTION 


FIG.  37.  —  Fa?ade  of  Baltimore  &  Ohio  Railroad  Go's.  Building,  Baltimore  Fire. 


FIRES  IN  FIRE-RESISTING   BUILDINGS  161 

seems  to  have  been  approximately  2800  degrees  or  more.  Cast- 
iron  radiators  and  typewriter  frames  were  found  in  some  places 
almost  completely  destroyed  by  oxidation,  but  had  melted  in  a 
few  cases  only.  Wire  glass  melted  in  a  number  of  instances."  * 

The  fire  not  only  traveled  low  down  from  building  to  building, 
but  high  overhead  as  well,  so  that  structures  were  attacked  at 
different  points  at  one  and  the  same  time  —  in  the  upper  stories 
from  the  great  waves  of  heat  and  embers  of  buildings  at  often 
considerable  distance.  The  custodian  of  the  Continental  Trust 
Company's  Building  stated  that  just  before  the  building  finally 
took  fire  in  the  upper  stories,  and  before  the  opposite  buildings 
were  in  flame,  every  window  sill  on  the  exposed  front  of  the  upper 
stories  was  covered  with  glowing  embers  to  a  depth  of  nearly 
six  inches,  piling  up  against  the  glass,  and  gradually  igniting 
the  window  frames  at  many  floors. 

It  is  thus  evident,  and  the  point  should  be  emphasized,  that 
no  construction  could  wholly  withstand  such  an  ordeal.  In  the 
report  of  the  Paterson  fire,  by  the  Continental  Fire  Insurance 
Company,  the  statement  was  made  that  a  fire-resisting  building 
is  not  an  exposure  to  another  fire-resisting  building  under 
ordinary  conditions,  and  judgment  upon  the  behavior  of  such 
buildings  in  the  Baltimore  fire  must  be  upon  the  logical  premise 
of  most  unusual  conditions. 

Effects  of  Fire.  —  Turning  now  to  a  more  detailed  account 
of  the  individual  buildings,  it  is  evident  that  a  somewhat  uni- 
form condition  of  affairs  was  to  be  expected  in  almost  every 
instance.  Thus,  in  sixteen  buildings  examined  by  the  writer 
in  great  detail,  no  woodwork  or  combustible  material  of  any 
nature  was  to  be  found  except  in  low  one-  or  two-storied  buildings 
which  escaped  serious  injury,  or  in  the  lower  story  or  stories 
of  a  few  notable  exceptions  in  high  buildings.  The  complete 
destruction  of  all  plastering  and  marble  finish  was  also  true  in 
every  high  building  but,  notwithstanding  these  uniform  condi- 
tions, points  of  great  interest  were  to  be  found  in  almost  every 
example.  The  examinations  were  made  but  two  days  after  the 
fire  and  before  anything  had  been  done  to  the  buildings  in 
question.  In  fact,  many  of  the  structures  were  still  smoking 
or  blazing  in  places. 

Non-flre-resisting  Buildings.  —  Over  ninety  per  cent,  of  the 
buildings  in  the  burned  area  were  fairly  substantial  brick  build- 
*  See  report  of  National  Fire  Protection  Association  Committee. 


162         FIRE   PREVENTION   AND   FIRE   PROTECTION 

ings,  mostly  of  ordinary  joisted  construction,  generally  of  small 
area,  ranging  from  four  to  five  stories  in  height.  These  suffered 
total  destruction  almost  without  exception.  Among  the  best 
of  this  class  of  construction  were  the  Law  Building  and  the 
American  Building,  of  which  only  portions  of  the  outer  walls 
remained  standing. 

Monumental  Buildings.  —  These  included  the  Postoffice, 
Court  House,  and  City  Hall,  all  structures  of  moderate  height 
with  heavy  exterior  walls. of  granite,  floors  of  brick  arches  or 
terra-cotta,  heavy  interior  walls  of  brick,  moderate  window  area 
exposure,  and  each  bounded  by  streets  on  all  sides.  The  Post- 
office  and  the  City  Hall  were  each  exposed  in  one  fagade  only, 
while  the  Court  House  was  badly  exposed  on  two  sides  to  build- 
ings opposite  which  were  severely  or  completely  damaged. 

The  use  of  fire  hose  within  these  three  buildings,  directed 
against  the  window  casings,  etc.,  during  the  entire  time  of 
exposure,  succeeded  in  keeping  the  flames  from  entering,  but 
great  damage  was  done  the  marble  and  granite  exteriors.  The 
result  would  undoubtedly  have  been  far  different  had  the  fire- 
resisting  Herald,  Calvert,  and  Equitable  Buildings  been  of  a 
more  combustible  nature  and,  in  these  cases,  most  certainly, 
the  fire-resisting  buildings  mentioned,  although  badly  damaged, 
served  to  protect  the  Court  House  in  large  measure. 

Fire-resisting  Buildings.  —  The  burned  area  included 
twenty-seven  buildings  which  could  fairly  be  called  fire-resistive. 
These  should  be  subdivided  into  those  structures  built  some 
twenty  to  twenty-five  years  ago,  after  methods  not  now  em- 
ployed, and  those  of  the  more  strictly  modern  type. 

In  the  former  class  were  the  Chamber  of  Commerce  and 
the  Baltimore  and  Ohio  Railroad  Office  Building;  A  photo- 
graph of  the  lower  stories  of  the  latter  building  is  shown  in 
Fig.  37,  illustrating  the  great  damage  done  the  exterior  granite 
work. 

The  more  modern  fire-resisting  buildings,  in  the  condition  of 
which  under  fire  test  we  are  particularly  interested,  included 
the  Equitable,  Herald,  Calvert,  Union  Trust  Company's,  Mary- 
land Trust  Company's,  Continental  Trust  Company's,  Mer- 
chants National  Bank,  and  the  Chesapeake  and  Potomac 
Buildings.  The  general  construction  and  the  effects  of  the 
fire  upon  these  buildings  will  be  described  very  briefly,  but  more 
extended  comment  upon  many  features  of  construction,  etc., 


FIRES   IN   FIRE-RESISTING   BUILDINGS  163 

will  be  given  in  various  other  chapters  dealing  with  details  of 
construction.  The  adjusted  fire  losses  in  these  several  buildings 
are  given  in  some  detail  because  they  form  the  basis  of  a  later 
discussion  in  this  chapter  on  the  ratio  of  fire  damage  to  sound 
value. 

The  Equitable  Building  was  a  ten-story  building  of  about 
100  feet  frontage  on  Calvert  street,  by  about  200  feet  on  Fayette 
street.  It  was  built  in  1891.  The  exterior  walls  were  granite 
for  a  height  of  three  stories  and,  like  all  other  granite  or  stone 
walls  which  passed  through  the  fire,  they  showed  much  scaling, 
especially  at  exposed  corners  or  soffits.  The  upper  stories  of 
brick  and  terra-cotta  were  in  passably  good  condition. 

This  building  was  connected  with  the  adjoining  Calvert 
Building  by  a  steel  and  terra-cotta  bridge,  but  the  principal 
exposure  came  from  the  rear,  where  was  located  a  low  non-fire- 
resisting  building  which  the  Equitable  Company  tried  to  buy 
when  the  new  building  was  erected.  This  dangerous  risk  backed 
up  to  the  interior  court  of  the  Equitable  Building,  and  it  was  in 
this  interior  court  that  evidence  of  the  greatest  heat  was  to  be 
seen.  The  enameled  bricks  of  the  court  walls  were  very  badly 
scaled  on  the  faces,  especially  around  the  windows,  where  great 
draughts  occurred. 

The  interior  framework  consisted  of  cast-iron  columns,  steel 
floor  beams,  and  shallow  terra-cotta  arches,  as  shown  in  Fig.  38. 


-Finished  Hardwood  F^por 


\No  Fire  Proofing  on 
bottom  of  Beam 

FIG.  38.  —  Floor  Construction,  Equitable  Building,  Baltimore  Fire. 

The  columns,  ranging  from  8  inches  by  8  inches  to  12  inches  by 
12  inches  in  size,  were  spaced  about  22  feet  centers,  with  girders 
between  of  10-inch  Fs.  The  floor  beams  were  9-inch  steel  I- 
beams,  ranging  from  6  feet  9  inches  to  8  feet  2  inches  on  centers, 
15  feet  5J  inches  span.  The  writer  was  informed  that  this 
system  of  wide  span  and  very  light  structural  framework  was 


164       FIRE   PREVENTION   AND   FIRE    PROTECTION 

designed  for  some  form  of  composition  or  patented  floor  which 
was  never  used.  As  built,  the  arches  consisted  of  6-inch  semi- 
porous  terra-cotta  partition  blocks,  sprung  from  flange  to  flange, 
laid  endwise,  thus  forming  a  kind  of  end-construction  arch, 
with  a  rise  of  4  inches  at  the  center.  The  flooring  consisted 
of  1-inch  flooring  on  2-inch  plank,  the  voids  over  the  arch 
haunches  being  unfilled.  The  result  was  about  what  one  would 
have  expected  from  such  an  abnormally  light  and  make-shift 
construction.  When  the  2-inch  rough  planking  burned  away, 
this  floor  construction  was  not  even  stable  enough  to  support 
the  various  safes  scattered  about  the  numerous  small  offices 
into  which  the  building  was  subdivided.  The  consequence  was 
that  most  safes  and  vault  doors  fell  through  to  the  basement, 
carrying  bay  after  bay  of  floor  arches  with  them. 

Also,  this  method  of  floor  construction  did  not  provide  any 
adequate  means  of  protecting  the  beam  soffits.  The  end  blocks 
used  as  skewbacks  were  supposed  to  hold  soffit  strips  of  tile  by 
means  of  beveled  edges,  and  some  metal  clamps  were  also  em- 
ployed. As  a  matter  of  fact,  few  of  the  beams  were  protected 
by  anything  more  than  about  one  inch  of  plaster,  thus  resulting 
in  the  serious  deflection  of  a  large  number  of  floor  beams. 

Another  great  mistake  in  design  was  the  absence  of  proper 
supports  for  the  vault  doors  supplied  for  all  floors.  These 
ordinary  vestibule  vault  doors  were  evidently  placed  on  top 
of  the  rough  plank  flooring  and  rested  over  a  floor  beam  along 
one  edge  of  the  vestibule  only.  On  the  burning  out  of  the  wood 
floor  the  vestibule  was  permitted  to  fall  enough  to  break  through 
the  floor  arch  beneath.  As  a  result,  one  door  remained  sus- 
pended in  a  dangerous  position  at  an  upper  floor,  while  the 
rest  were  buried  in  the  debris  in  the  basement.  The  floor 
arches  should  either  be  substantial  enough  to  carry  such  loads 
or  else  additional  beam  supports  should  be  provided. 

The  partitions  throughout,  of  4-inch  "Lime-of-Teal,"  or  a 
species  of  plaster-of-Paris  blocks,  were  completely  disintegrated 
and  generally  reduced  to  lifeless  debris  or  powder  scattered  over 
the  floors.  The  tremendous  weight  of  so  many  fallen  partitions 
must  also  have  contributed  no  small  share  to  the  failure  of  the 
floor  arches.  If  one  were  inclined  to  place  any  reliance  on 
plaster  blocks  for  fire-resistance,  the  repeated  experiences  of 
this  material  in  the  Baltimore  fire  would  soon  dispel  the 
illusion. 


FIRES    IN   FIRE-RESISTING    BUILDINGS 


165 


The  adjusted  insurance  loss  was  as  follows: 


Sound 
value. 

Salvage. 

Fire  loss. 

General  conditions                  

$6,950.00 

$6,950.00 

Masonry    

121,674.00 

59,214.00 

62,460.00 

Granite                              

76,797.00 

29,572.00 

47,225.00 

Roof                                                   

6,528,00 

2,528.00 

4,000.00 

Exterior  marble     

8,609.00 

3,109.00 

5,500.00 

Steel  and  cast  iron  
Ornamental  iron 

93,367.00 
51,650.00 

53,705.00 
18,719  00 

39,662.00 
32,931  00 

Fireproofing  and  terra-cotta  floors  
Interior  marble                                  

68,804.00 
56,250.00 

4,000.00 
5,500.00 

64,804.00 
50,750.00 

Terra-cotta  and  setting  

26,170.00 

8,170  00 

18,000.00 

Safes                                        

20,000.00 

5,516.00 

14,484.00 

Carpentry  work 

102,120  00 

620  00 

101,500  00 

Plastering                         

36,951.00 

36,951.00 

Wire  lath  and  plastering                   

6,342.00 

6,342  00 

Painting 

16,855  00 

16,855  00 

Glass  and  glazing                           

15,360.00 

15,360.00 

Hardware 

6,600  00 

100  00 

6,500  00 

Wall  tiling                  

18,590.00 

18,590.00 

Asphalt  floors                                          .  . 

6,000  00 

6,000  00 

Turkish  baths  

7,008.00 

7,008.00 

Staging                                                     .  . 

5,000.00 

5,000.00 

Cleaning  out  building 

8,500  00 

Architects'  fees                        

18,930  00 

10,300  00 

8,630.00 

Furniture 

55,520  00 

14,724  00 

40,796  00 

Boiler  plant,  etc  

19,823.00 

13,932.02 

5,890.98 

High  pressure  piping                           ...    . 

8,183  88 

4,630  00 

3,553  88 

Heating  and  ventilating  apparatus  

37,385.00 

3,880.00 

33,505.00 

Generator  plant  
Elevators                                 .   . 

22,646.00 
54,969  65 

14,676.00 
17,950  00 

7,970.00 
37,019  65 

Plumbing,  fire  pump,  etc  

36,290.00 

2,575.00 

33,715.00 

Electric  wiring        

19,800  00 

19,800  00 

Fixtures 

6,793  00 

1,450  00 

5  343  00 

Total 

$1,037,965  53 

$274,870  02 

$771,595  51 

The  appraisers'  report  contained  the  following  conclusion : 

Had  this  building  been  properly  constructed,  there  would 
not  have  been  over  a  50  per  cent.  loss.  ...  A  large  portion  of  the 
damage  would  have  been  saved  had  the  fireproofing  been  prop- 
erly done,  proving  conclusively  that  too  much  care  cannot  be 
taken  in  looking  after  the  construction  of  a  building  if  the  fire- 
proofing  is  to  be  of  any  practical  use. 

The  Baltimore  Herald  Building  was  a  six-story  building 
at  the  corner  of  St.  Paul  and  Fayette  streets.  While  not  as 
large  as  most  of  the  other  buildings  here  described,  it  was  still 
interesting  in  several  particulars. 

On  the  exterior,  the  sandstone  of  the  lower  two  stories  was 
considerably  damaged,  requiring  extensive  reconstruction.  The 
pressed  brick  and  ornamental  terra-cotta  fronts  of  the  upper 
stories  had  to  be  entirely  rebuilt,  particularly  owing  to  the 


166 


FIRE   PREVENTION   AND    FIRE    PROTECTION 


damage  to  the  brickwork.     Possible  salvage  in  the  terra-cotta 
was  offset  by  the  expense  of  resetting. 

On  the  interior,  wood  floors  and  screeds  had  entirely  dis- 
appeared, and  the  cinder  concrete  filling  was  soft  and  lifeless. 
Although  all  of  the  end-construction  porous  terra-cotta  floor 
arches  were  in  place,  they  were  devoid  of  ceiling  plastering,  and 
arches  were  cracked  and  sagged  in  the  center  to  a  considerable 
extent  on  several  floors.  This  was  due  to  faults  in  the  floor 


FIG.  39.  —  Inter! 


design.  The  floor  girders  were  generally  of  too  shallow  a  depth 
for  the  considerable  spans  employed  and,  being  firmly  embedded 
in  extra  heavy  masonry  walls  at  wall  bearings,  were  thus  fixed 
at  the  ends.  The  expansion  under  the  heat  caused  the  girders 
and  beams  either  to  sag  or  " crown"  at  the  center.  This  re- 
sulted in  a  general  weakening  of  the  floor  arches.  Some  lower 
faces  of  arches  were  off  and  protections  of  lower  flanges  of  beams 
and  girders  were  broken  in  places,  especially  on  upper  floors. 

Two  kinds  of  partitions  were  in  evidence  in  this  building  — 
terra-cotta  and  plaster-block.     Most  of  the  former  were  in  fair 


FIRES   IN    FIRE-RESISTING    BUILDINGS 


167 


condition,  while  those  made  of  plaster-blocks  were  either  down 
or  so  disintegrated  that  the  finger  could  easily  be  pushed  through 
the  webs  of  the  blocks.  Fig.  39  shows  the  condition  of  the  plas- 
ter-block partitions,  and  the  sagging  of  the  floor  girders  referred 
to.  The  terra-cotta  column  casings  were  also  largely  in  place, 
but  in  only  fair  condition. 

The  court  windows  were  provided  with  tinned  shutters,  which 
were  evidently  closed  at  the  time  of  the  fire,  as  the  sheets  of  tin 
were  standing  upright  within  the  window  spaces  but  entirely 
devoid  of  any  traces  of  wood  cores  and  absolutely  useless. 
They  had  evidently  been  held  closed  by  latches  screwed  into 
the  wooden  window  frames,  and  were  hence  free  to  open  as 
soon  as  this  wood  was  consumed. 

The  adjusted  fire  loss  was  as  follows: 


Sound 
value. 

Salvage. 

Fire  loss. 

Excavation  

$4,500 

$4,500 

Foundation                        

10,850 

10,440 

$410 

Stone  ashlar  

20,270 

12,100 

8,170 

Common  brick  
Pressed  brick 

24,350 
2  729 

17,350 

7,000 
2  729 

Ornamental  terra-cotta  
Roofing 

11,000 
837 

11,000 
837 

Sheet  metal  and  skylights  
Plastering 

2,496 
6  436 

160 

2,336 
6  436 

Floor  arches  

7,978 

3,989 

3,989 

Partitions 

2,898 

2  898 

Concrete  fill.'.  

1,058 

1,058 

Steel  work                                   ... 

42,389 

29,389 

13  000 

Ornamental  iron 

10,025 

6  407 

3  618 

Marble     

3,077 

3,077 

Tile  Mosaic 

4  325 

100 

4  225 

Hardware  

1,600 

1,600 

Glass  

2,450 

2  450 

Carpentry.  .  . 

14,762 

14,762 

Office  grille             .    . 

423 

423 

Painting  

3,150 

3,150 

Mail  chute  

600 

50 

550 

Plumbing 

5  660 

500 

5  160 

Elevators  

17  706 

4  000 

13  706 

Radiators  and  piping  .  .   

7,679 

1,535 

6,144 

Wiring  and  fixtures.    . 

3  000 

3  000 

Vaults  

3  840 

90 

3  750 

Sidewalk  and  curb  

392 

246 

146 

Concrete  floor  

648 

448 

200 

Cleaning  and  scaffolding  

3  100 

Total  

$217,131 

$91,306 

$128  925 

Deduct  for  junk  

1  320 

$127,605 

The  Calvert  Building  is  a  twelve-story  building,  corner  of 
Fayette  and  St.  Paul  streets.     The  lower  two  stories  were  of 


168         FIRE    PREVENTION    AND    FIRE    PROTECTION 


sandstone,  which  was  badly  scaled  in  places,  especially  near  the 
corner  of  the  building.  The  upper  stories  of  brick  and  orna- 
mental terra-cotta  trimmings  appeared  from  the  street  about 
as  good  as  new,  and,  indeed,  viewing  the  building  from  some 
distance,  it  was  hard  to  realize  that  the  structure  had  really 
passed  through  the  ordeal  of  fire,  had  not  the  absence  of  all 
window  frames  and  sash  so  testified.  A  closer  examination, 
however,  revealed  considerable  injury  to  the  terra-cotta  trim- 
mings and  brickwork,  especially  the  cornice.  Compare  with 
Chapters  VII  and  XX. 

On  the  interior,  the  steel  frame  was  intact  and  suffered  no 
injury  whatever  with  the  single  exception  of  one  column  on  the 
eighth  floor.  This  was  a  box  column  made  of  two  channels 
and  two  plates,  and,  from  evidences  on  the  floor  around,  it  was 
subjected  to  a  tremendous  heat,  due  to  the  burning  of  large 
quantities  of  paper  and  office  supplies.  The  partial  failure  of 
the  terra-cotta  column  covering  resulted  in  the  " upset "  or 
settling  down  on  itself  of  the  column  about  four  inches. 

The  floor  framing  generally  consisted  of  15-inch  beams  and 
15-inch  Haydenville  semiporous  end-construction  terra-cotta 
arches.  Portions  of  the  lower  flanges  scaled  off,  exposing  the 
cross  webs  in  the  blocks,  but  on  the  whole  the  floors  were  in 
excellent  condition,  and  the  architect  of  the  building  expressed 
himself  as  much  pleased  with  the  showing.  The  condition  of 
this  building  was  a  great  recommendation  for  deep  and  sub- 
stantial floor  construction. 

The  terra-cotta  partitions  were  practically  wrecked  through- 
out as  far  as  reconstruction  was  concerned,  due  to  the  intro- 
duction of  wooden  sash,  in  the  upper  portions  of  the  corridor 
partitions,  for  transmitting  light  from  offices  to  corridors. 

Sound  value  of  building,  $634,075.00  Per  cent. 

Fire  damage,  $363,256.00  or 57.  3 

Damage  to  structural  steel 1 .  37 

floor  arches 7.  47 

partitions 99.  5 

cinder  fill 66.  6 

stonework 58.  6 

face  brick 48.  5 

ornamental  terra-cotta 73.  5 

ornamental  iron 37. 

marble 97.  5 

plastering 97.  4 

woodwork 95. 1 


FIRES   IN   FIRE-RESISTING   BUILDINGS  169 

The  Union  Trust  Company's  Building,  at  the  corner  of 
Fayette  and  Charles  streets,  on  the  northern  confines  of  the  fire 
area,  is  a  ten-story  and  high  basement  building  of  skeleton 
construction.  The  lower  three  stories  were  of  sandstone  which 
was  badly  scaled,  especially  at  the  corners  of  piers  and  reveals. 
The  upper  stories  were  of  brick  with  ornamental  terra-cotta 
trimmings  and  heavy  overhanging  cornice.  The  terra-cotta 
panels  or  spandrels  between  the  windows  and  the  ornamental 
window- jamb  mouldings  of  the  same  material  were  badly  broken 
in  many  places.  The  terra-cotta  cornice  was  considerably 
damaged.  The  exterior  face  brick  appeared  to  be  in  generally 
good  condition,  except  that  the  brick  quoins  or  raised  belt 
courses  were,  in  many  instances,  split  off  even  with  the  face  of 
the  wall.  This  same  condition  was  to  be  seen  in  other  build- 
ings, and  ornamental  terra-cotta  which  was  modeled  with  con- 
siderable relief  or  in  highly  ornamented  forms,  usually  suffered 
much  more  damage  than  flatter  or  plainer  surfaces.  The  two 
street  walls  of  this  building  were  afterwards  entirely  removed, 
having  been  condemned  by  the  city  Building  Department,  there- 
by adding  materially  to  the  loss. 

All  of  the  window  frames  were  completely  burned  out,  but 
all  cast-iron  mullions  save  one  were  standing,  but  generally 
badly  warped. 

On  the  interior,  the  steel  frame  was  absolutely  intact,  the  only 
injury  being  a  few  sagged  beams.  The  floor  arches  of  end- 
construction  porous  terra-cotta  were  in  very  creditable  con- 
dition considering  the  tremendous  heat  to  which  this  building, 
in  particular,  was  subjected.  All  floor  and  roof  arches  were  in 
place,  but  the  lower  faces  of  the  blocks  had  scaled  off  of  portions, 
particularly  in  the  upper  stories.  The  strength  of  the  floor 
arches  after  the  fire  was  well  proven  by  a  safe,  said  to  weigh 
3500  pounds,  which  was  found  lying  across  the  center  of  a  second 
floor  arch.  Of  wood  floor  and  screeds,  not  a  trace  remained. 
The  tile  column  coverings  were  largely  in  position,  but  unstable, 
due  to  the  weakening  of  the  mortar  joints.  Tile  partitions 
were  badly  broken,  and  if  not  down,  were  also  weak  in  the 
mortar  joints. 

A  somewhat  exceptional  condition  of  affairs  was  found  in 
this  building  with  reference  to  the  stairway.  This  had  appar- 
ently been  constructed  of  cast-iron  strings  and  risers,  and 
marble  treads  and  platforms,  but  of  the  entire  ten  stories  only 


170         FIRE   PREVENTION   AND   FIRE   PROTECTION 

a  few  strings  were  in  place  near  the  top  floor.  Practically  the 
entire  stairway  was  a  heap  of  ruins  in  the  basement  and  first 
story.  The  only  way  of  examining  the  upper  floors  was  by 
means  of  the  exterior  fire  escape. 

The  president  of  the  Union  Trust  Company  informed  the 
writer  that  every  hope  had  been  entertained  of  saving  the  build- 
ing up  to  late  on  Sunday  evening.  The  building  was  equipped 
with  standpipes,  and  hose-reels  were  in  readiness  on  every  floor, 
as  well  as  wet  blankets,  before  the  most  exposed  windows,  as 
the  fire  approached  this  location.  But  the  orders  of  those  who 
had  charge  of  fighting  the  conflagration  at  this  point,  to  blow 
up  with  dynamite  the  combustible  -toy  store  opposite,  were 
unfortunately  delayed  until  that  building  was  in  flames.  The 
explosion  only  made  matters  worse.  It  blew  in  all  the  windows 
of  the  Union  Trust  Building,  and  sheets  of  flame  attacked  the 
entire  structure  at  every  opening  at  practically  the  same  moment. 

The  sound  value  of  building  was  $348,795.00. 

The  fire  damage  was  $214,488.00;  or  61.5  per  cent.  Items 
of  damage  included  structural  steel,  1.03  per  cent.;  floor  arches, 
40  per  cent.;  cinder  filling,  80  per  cent.;  partitions,  80  per  cent.; 
stonework,  95  per  cent.;  brickwork,  31.9  per  cent.;  terra  cotta, 
100  per  cent.;  ornamental  iron,  94.5  per  cent.;  marble  and  mosaic, 
97.7  per  cent.;  plastering,  100  per  cent. 

The  Maryland  Trust  Company's  Building  was  a  ten-story 
and  attic  building,  corner  of  East  German  and  South  Calvert 
streets,  built  in  1900.  The  exterior  walls,  self-supporting  to 
fifth  story  and  carried  on  the  steel  frame  above  that  level,  were 
faced  with  granite  on  the  street  fronts  in  first  and  second  stories, 
above  which  they  were  of  pressed  brick  and  terra-cotta  trim 
with  a  heavy  ornamental  terra-cotta  cornice.  The  steel  frame 
consisted  generally  of  built  steel  columns,  double  24-inch 
I-beam  girders  and  10-inch  beams.  The  floors  were  of  9-inch 
semiporous  end-construction  terra-cotta  arches,  the  beam 
soffits  being  protected  by  solid  terra-cotta  wedge  strips,  1  inch 
thick,  held  in  place  by  the  arch  skewbacks  and  by  the  plastering. 
The  girders  were  protected,  where  projecting  below  the  floor 
arches,  by  means  of  3-inch  hollow  tile  blocks  resting  on  the 
lower  flanges  of  girder  beams,  the  soffits  being  protected  by 
1-inch  solid  soffit  tile  held  by  clips  around  the  girder  flanges, 
and  by  the  plastering.  Interior  columns  were  protected  by  4-inch 
hollow  tile  blocks,  partitions  were  made  of  4-inch  hollow  tile 
with  wooden  door  frames  and  top  sash.  The  end  wall,  toward 


FIRES   IN   FIRE-RESISTING   BUILDINGS  171 

the  Carrolton  Hotel  and  toward  the  source  of  the  conflagration, 
was  provided  with  tinned  shutters  over  all  windows.  It  is 
impossible  for  any  except  eye  witnesses  to  say  whether  these 
shutters  failed  from  the  heat  of  the  burning  hotel,  thus  allowing 
the  flames  to  enter  the  Trust  Building,  or  whether  they  finally 
succumbed  only  after  fire  had  entered  the  building  from  the 
structures  across  German  street.  However  that  may  be,  they 
were  finally  reduced  to  empty  shells  of  warped  and  twisted  tin, 
the  outer  and  inner  faces  of  which  were  as  much  as  12  to  15 
inches  apart  in  some  cases,  caused  by  the  rapid  generation  of 
gas  from  the  wood  cores. 

Damage  to  Building.  —  The  sound  value  of  building  was 
$404,005,  of  which  $242,279  was  the  adjusted  fire  loss.  The 
items  of  stonework,  plastering,  roofing,  and  sheet  metal,  marble 
and  mosaic,  painting  and  glazing,  carpentry  work,  hardware, 
and  electric  work  were  all  total  losses.  The  exterior  granite 
was  badly  damaged,  terra-cot ta  trim  was  chipped  and  broken, 
and  many  of  the  faces  of  the  pressed-brick  piers  were  badly 
scaled.  The  ornamental  terra-cotta  suffered  a  loss  of  75  per 
cent,  of  sound  value,  brickwork  55  per  cent. 

On  the  interior,  the  steel  frame  was  generally  in  good  condi- 
tion, save  in  the  attic  where,  probably  owing  to  the  storage  of 
paper,  etc.,  which  evidently  produced  a  great  heat,  several 
columns  had  deflected,  one,  made  of  two  10-inch  channels 
riveted  back  to  back,  being  buckled  about  18  inches  out  of  line, 
thus  settling  and  permitting  the  roof  girders  to  deflect.  The 
structural  steel  was  practically  undamaged  below  the  attic 
level,  the  entire  fire  loss  on  this  portion  of  the  construction  being 
but  6  per  cent. 

The  floor  arches  were  all  in  position,  even  supporting  heavy 
portable  safes  after  the  fire,  although  the  lower  faces  of  the  arch 
blocks  were  scaled  off  on  many  of  the  upper  floors.  Beam 
soffits  were  mostly  in  place,  but  girder  protections  were  gen- 
erally missing.  Column  coverings  and  partitions  were  largely 
standing,  but  damaged  and  weakened.  The  fire  loss  to  the  tile 
fireproofing  was  70  per  cent. 

The  Continental  Trust  Company's  Building.  —  This  was 
a  fourteen-story  skeleton  construction  building,  erected  in  1901 
at  the  southeast  corner  of  East  Baltimore  and  South  Calvert 
streets.  The  two  street  walls  were  stone-faced  up  to  the  third 
story,  above  which  they  were  of  pressed-brick  and  terra-cotta. 


172         FIRE    PREVENTION    AND    FIRE    PROTECTION 

The  east  or  end  wall,  and  the  south  or  rear  wall,  were  of  brick 
with  a  4-inch  facing  of  pressed- brick,  both  of  these  walls  being 
indented  by  exterior  light  courts.  All  walls  were  pierced  with 
a  great  number  of  windows,  so  as  to  give  maximum  light  to  all 
offices.  Brick  walls  were  generally  12  inches  thick,  carried  on 
the  steel  frame  at  each  floor,  with  4-inch  inside  furring  tile. 
The  court  windows  were  separated  by  cast-iron  mullions. 

The  steel  frame  was  of  built-up  columns,  double  15-inch 
I-beam  girders  24  feet  on  centers,  and  15-inch  I-beam  joists  6  feet 
on  centers.  The  floor  arches  were  16-inch  semi-porous  end 
construction  arches,  the  beam  soffits  being  protected  by  2-inch 
thick  grooved  soffit  tile  held  in  place  by  the  skewbacks.  Soffits 
of  girders  were  similarly  protected.  Column  casings  were 
partly  3-inch  and  partly  4-inch  hollow  tile.  Partitions  were  of 
hollow  tile,  5  inches  thick  along  corridors,  and  3  inches  thick 
between  the  numerous  rooms. 

Structural  Damage.  —  The  sound  value  of  this  building  was 
$1,028,461.  The  fire  loss  was  $666,328,  or  practically  65  per 
cent.  This  must  have  been  a  great  surprise  to  the  owners,  — 
an  experience  hardly  calculated  to  recommend  fire-resisting 
construction  —  in  as  much  as  the  building  was  apparently 
well-designed,  well-built,  and  suited  to  the  needs  of  a  modern 
office  building.  But  it  is  plain  from  the  behavior  of  this  struc- 
ture under  severe  fire  test  that  it  was  a  good  example  of  poor 
workmanship,  and  skeleton  construction  carried  to  the  extreme 
of  lightness. 

The  large  glass  or  window  area,  with  the  minimum  of  pier  or 
spandrel,  combined  also  with  poor  workmanship,  resulted  in  a 
veneer  which  did  not  possess  the  requisite  stability  under  fire 
test.  The  exterior  stone,  face  brick,  and  terra-cotta  were  all 
considerably  chipped  and  broken,  the  experience  in  this  instance 
being  no  worse  than  with  these  same  materials  in  most  of  the 
other  buildings.  But  in  the  court  walls,  errors  in  inefficient 
design  and  slighted  work  caused  much  avoidable  damage.  The 
spandrel  beams  over  the  court  windows  were  insufficiently  pro- 
tected, thus  allowing  the  distortion  of  those  members,  which 
in  turn  resulted  in  the  falling  of  considerable  portions  of  the 
curtain  walls,  notably  at  the  seventh,  eighth,  and  ninth  floors. 
The  cast-iron  mullions  were  too  thin  and  too  light  to  offer  any 
material  resistance  to  heat,  the  result  being  that  they  were 
practically  all  warped  or  broken,  thus  adding  to  the  distortion 


FIRES   IN   FIRE-RESISTING   BUILDINGS 


173 


of  the  spandrel  members.  Furthermore,  the  four-inch  pressed- 
brick  facing  of  the  court  walls  was  stripped  off  in  considerable 
areas  leaving  the  insufficient  metal  wall-ties  exposed.  Wire  or 
flat  metal  ties  are  a  poor  substitute  for  brick  headers. 

Other  than  the  spandrel  members  and  mullions  mentioned 
above,  the  steel  frame  was  uninjured.  The  floor  arches  were  also 
in  excellent  condition,  as  were  the  beam  and  girder  protections. 

The  column  protections,  however,  revealed  the  fact  that  much 
carelessness  and  poor  workmanship  had  been  permitted  in 
trying  to  care  for  the  installation  of  piping  and  wire  conduits 
within  the  plaster  finish  line,  the  result  being  that  the  tile  blocks 
were  badly  cut  and  broken  in  many  instances  (see  Fig.  59, 
Chapter  XII).  This  not  only  rendered  the  column  protections 
of  little  avail,  but  menaced  the  partitions  butting  into  the  col- 
umns as  well.  Partitions  were,  in  general,  greatly  damaged. 

The  adjusted  fire  loss  was  as  follows: 


Sound  value. 

Salvage. 

Fire  loss. 

General  conditions  

$2,811.00 

S500.00 

$2,311.00 

79  793  61 

41  158  13 

38  635  48 

Granite 

41,706  32 

17,360  32 

24.346  00 

Steel  

101,695.00 

92,141.85 

9,553  15 

Fireproofing 

63,030  99 

28.894  00 

34.136  99 

Terra-cotta 

39  982  50 

11,107  50 

28  875  00 

Painting  and  decorating  

29,600  00 

29,600  00 

Carpentry  and  mill  work 

111,912  64 

412  64 

111,500  00 

Ornamental  iron   

65,756  95 

15.386  95 

50,370.00 

Plastering  and  lath  
Marble  and  setting.  

29,997.00 
108.000  00 

5.900  66 

29,997.00 
102,100  00 

Vault  doors  

6,500  00 

400  00 

6,100  00 

Finished  hardware  

8,500.00 

8.500  00 

Cement  floors  and  concrete       

7.138  64 

2  816  69 

4,321  95 

Glass  and  glazing  
Mail  chute  

14,427.00 
1,850.00 

14,427.00 
1,850.00 

Scaffolding 

2500  00 

Safety  deposit  vault                     

78.000  00 

77.000.00 

1,000  00 

Sheet  metal  and  roofing  
Boilers,  heating  and  ventilating     .  .  . 
Plumbing,  sewerage  and  gas  
Electric  wiring  
Refrigerating  plant 

3,751.57 
43.151.00 
42,441.00 
20,855.00 
9  583  00 

1.588.75 
11,270.00 
10,245.00 
400.00 
2,798.00 

2,162.82 
31,881.00 
32.196.00 
20,455.00 
6,785  00 

Elevators  and  plant  ......  
Flash  signals  and  indicators  
Electric  6xtures  
General  removal  of  present  debris. 
Architect  and  superintendence  

51,300.00 
5,600.00 
10,800.00 

"50.278.'  38 

20,000.00 
'2,600^00 
"30.636!  22 

31,300.00 
5.600.00 
8,200.00 
7,983.00 
19.642.16 

$1,028,461.60 

$372.616.05 

$666,328.55 

No  one  fact  was  more  in  evidence  in  this  building  than  the 
tremendous  havoc  which   the  fire   played  with   the  very  large 


174         FIRE   PREVENTION   AND   FIRE   PROTECTION 

quantities  of  marble  used  in  wainscots,  bases,  floors,  etc.  The 
floor  arches  were  literally  covered  with  marble,  broken  and 
lifeless.  The  marble  stair  treads  and  landings  were  also  gone 
throughout. 

The  Merchants  National  Bank  Building.  —  This  was  a 
seven-story  building  with  load-bearing  walls  of  granite  on  the 
street  fronts.  The  items  of  especial  interest  are  briefly  as  fol- 
lows: Granite  walls  facing  the  worst  exposures  were  badly 
damaged,  fire  loss  52  per  cent.  Ten-inch  semi-porous  end-con- 
struction tile  arches  in  almost  perfect  condition,  owing  largely 
to  the  dividing  webs  of  the  arch  blocks  which  were  about  one 
inch  thick.  Brick  column  coverings  were  intact  and  uninjured. 
Partitions  of  4-inch  tile  badly  damaged. 


FIG.  40.  —  Interior  of  Chesapeake  &  Potomac  Telephone  Building, 
Baltimore  Fire. 

The  Chesapeake  and  Potomac  Telephone   Company's 

Building  was  a  seven-story  and  basement  building,  built  about 


FIRES   IN   FIRE-RESISTING   BUILDINGS 


175 


1890.  While  neither  as  high  nor  as  large  in  area  as  most  of 
the  structures  previously  described,  yet  the  exposure  was  severe 
and  the  damage  considerable,  including  the  spalling  and  break- 
ing of  stone  and  face-brick  in  exterior  walls,  and  the  complete 
destruction  of  all  interior  finish,  combustible  and  otherwise. 
Nevertheless,  this  building  furnished  a  remarkable  example  of 
the  ability  of  terra-cotta  floor  arches  to  withstand  severe  test 
by  fire,  and  a  careful,  personal  inspection  of  the  interior  shortly 
after  the  fire  fully  convinced  the  writer  that  terra-cotta  floor 
arches,  combining  proper  material,  adequate  mass,  and  careful 
workmanship,  will  answer  every  requirement  under  fire  test 
which  could  reasonably  be  expected  of  them. 

The  blocks  were  of  old-style  Raritan  manufacture,  porous, 
side  construction,  10  inches  deep,  but  of  small  size  and  thick 
webs.  The  setting  had  evidently  been  carefully  and  con- 
scientiously done.  Excepting  some  of  the  lower  faces  which 
were  broken  off  on  the  sixth  floor  where  the  fire  was  very  hot, 
the  arches  were  in  almost  perfect  condition  (see  Fig.  40). 
1  The  4-inch  tile  partitions  did  not  fare  so  well.  They  were 
mostly  standing,  but  unstable  and  damaged. 

The  adjusted  fire  loss  was  as  follows: 


Sound  value. 

Loss. 

General  conditions  

$1,080 

$532  00 

Excavation  and  masonry,  footings  and  basement.  .  . 
Granite  and  brown  stone 

4,986 
10  865 

150.00 
6  675  00 

Common  and  face  brick  
Concrete  and  asphalt  floors                              

15,580 
6  890 

5,200.00 
1  000  00 

Fireproofing 

7  600 

2  100  00 

Interior  marble                                  

3  190 

2  900  00 

Plastering  and  wire  lath 

1  660 

1  660  00 

Sheet  and  metal  work     

2,760 

2,420  00 

Structural  iron                                                          ...    . 

20  180 

150  00 

Architectural  iron  

7,850 

2,032  00 

Plate  and  wire  glass                              

1  025 

1  025  00 

Painting  and  decorating 

1  760 

1  760  00 

Hardware,  fine  and  rough            

1  090 

950  00 

Boilers,  heating  and  ventilatin^ 

4  772 

1  710  00 

Finished  carpentry  -.  

6  540 

6,340  00 

Rough  carpentry         .                                 

1  878 

1  777  77 

Plumbing 

3  862 

2  775  00 

Elevators  .    .            

4  625 

2  050  00 

Electric  wiring  and  gas  fixtures 

1,331 

1,206  00 

Plans,  specifications,  and  superintending,  5  per  cent. 

$109,524 
5,476 

$44,412.77 

$115,000 

176         FIRE    PREVENTION    AND    FIRE    PROTECTION 

Low  Buildings.  —  A  number  of  low  bank  buildings  (generally 
one  or  two  stories  in  height)  within  the  burned  area,  escaped 
with  comparatively  little  damage.  This  was  due  in  part  to 
their  sheltered  locations,  but  principally  to  the  fact  that  the 
maximum  heat  and  attack  of  the  conflagration  traveled  high, 
and  hence  over  the  low  structures.  Most  of  them,  however, 
were  partially  wrecked  by  the  falling  walls  of  adjacent  or  nearby 
buildings,  and  in  some  cases,  where  the  exposure  was  severe, 
the  interiors  were  burned  out. 

The  lesson  taught  by  these  buildings  is  that  roofs  of  low 
structures  must  be  especially  strong  to  withstand  the  precipi- 
tation of  debris  from  neighboring  walls,  etc. 

Concrete  Construction  in  Baltimore  Fire.  —  Competent 
authorities  are  quite  diverse  in  their  opinions  regarding  the  fire 
test  of  concrete  construction  in  the  Baltimore  fire. 
.    The  report  of  the  National  Fire  Protection  Association  Com- 
mittee contains  the  following: 

Several  of  the  low  buildings  and  the  four-story  building  of 
the  United  States  Fidelity  and  Guaranty  Company  had  concrete 
floor  arches.  In  the  low  buildings  the  test  of  the  arches  was  not 
severe,  but  the  upper  floors  of  the  four-story  building  were  sub- 
jected to  severe  heat.  Also  in  speaking  of  the  latter  building, 
All  concrete  floors,  beams,  and  columns  are  intact  and  appar- 
ently in  good  condition,  except  some  of  the  front  floor  arches  on 
the  third  and  fourth  floors  which  have  cracked  and  sagged 
slightly.  The  corners  have  broken  off  of  concrete  columns  and 
girders  on  fourth  floor,  exposing  part  of  the  reinforcing  metal. 
.  .  .  The  indications  are  that  while  the  heat  was  severe  in  this 
building,  particularly  in  the  front  parts  of  the  third  and  fourth 
floors,  the  temperatures  were  not  extreme. 

On  the  other  hand,  Prof.  Charles  E.  Norton  states  in  Report 
No.  XIII  of  the  Insurance  Engineering  Experiment  Station,  on 
"The  Conflagration  in  Baltimore": 

The  building  of  the  United  States  Fidelity  and  Guaranty 
Company  is  an  interesting  example  of  reinforced  concrete.  As 
near  as  I  could  ascertain,  it  wTas  subjected  to  a  severe  fire,  and 
I  found  evidence  of  temperatures  up  to  the  softening  point  of 
cast-iron.  The  condition  of  the  lower  part  of  the  structure  and 
apparently  of  the  whole  structure  showed  the  great  fire-resisting 
powers  of  this  type  of  building. 

General  Deductions:  Baltimore  Fire.  —  The  Baltimore 
conflagration,  served  to  bring  home  to  architects,  engineers, 
contractors,  and  manufacturers,  a  vast  number  of  very  vital 


FIRES   IN    FIRE-RESISTING    BUILDINGS  177 

and  practical  truths  relative  to  the  theory  and  practice  of  fire 
protection,  none  of  which  were  new,  but  all  of  which  were  so 
emphasized  in  this  experience  as  to  leave  no  adequate  excuse 
for  their  disregard  in  later  practice.  Many  of  these  have 
already  been  touched  upon  in  the  previous  detailed  descriptions 
of  the  various  buildings,  and  many  more  will  be  considered  at 
even  more  length  in  various  chapters  pertaining  to  particular 
features  or  details  of  construction;  but  the  great  lessons  empha- 
sized by  this  fire  were,  briefly,  (a)  the  necessity  for  protection 
against  the  " exposure  hazard,"  which  is  considered  at  more 
length  in  Chapter  XIV,  and  (6)  the  prevalence  of  skimped  or 
slighted  work  (which  is  discussed  at  more  length  in  Chapter  X 
and  elsewhere),  and  the  improper  use  of  proper  materials,  as 
will  be  pointed  out  in  various  following  chapters. 

The  Rochester  Fire.  —  Less  than  three  weeks  after  the 
Baltimore  conflagration,  a  serious  fire  occurred  in  Rochester, 
N.  Y.,  involving  a  loss  of  about  $3,000,000.  On  February  25 
and  26,  1904,  the  so-called  " Granite  Building"  fire  again  demon- 
strated the  folly  of  neglecting  the  most  ordinary  precautions 
against  exposure  hazards,  revealing  an  intercommunication 
between  what  would,  at  that  time,  have  been  called  a  fire- 
resisting  building,  and  other  buildings  which  were  not  only 
non-fire-resisting,  but  most  dangerous  hazards. 

At  the  corner  of  St.  Paul  and  Main  Streets  was  the  thirteen- 
story  Granite  Building,  with  self-supporting  walls,  enclosing 
an  iron  framework  of  circular  cast-iron  columns  and  steel  I-beam 
girders  and  floor  beams.  The  floor  arches  were  generally 
12-inch  end  construction  porous  terra-cotta,  with  three  cavities 
and  1-inch  webs,  the  skewbacks  dropping  below  the  beam  flanges 
in  order  to  hold  dovetailed  flange  tiles.  The  columns  were 
encased  by  IJ-inch  solid  porous  terra-cotta,  and  partitions  were 
of  4-inch  tile  with  wooden  strips  at  the  top. 

The  street  floor,  basement,  and  five  stories  of  the  north  wing 
of  this  building  were  occupied  by  a  dry-goods  company,  which 
also  occupied  the  whole  of  the  adjacent  five-story  ordinary  con- 
struction building,  as  well  as  a  wholesale  building  of  seven 
stories,  also  of  unprotected  construction,  which  was  only  sepa- 
rated from  the  Granite  Building  by  a  35-foot  alleyway.  Between 
the  Granite  Building  and  the  adjacent  store  on  the  east  there 
existed  unprotected  communicating  openings  at  the  first  to 
fifth  stories,  these  aggregating  not  less  than  2000  square  feet; 


178         FIRE    PREVENTION    AND    FIRE    PROTECTION 

while  the  wholesale  building  to  the  north  was  connected  with 
the  Granite  Building  by  means  of  an  arcade  or  tunnel  under 
the  alleyway,  and  also  by  a  bridge  with  openings  at  the  second 
to  fifth  .floors,  these  latter  being  protected  by  rolling  iron  shut- 
ters. A  light  court  with  many  unprotected  windows  also 
indented  the  easterly  wall  of  the  Granite  Building. 

The  fire  originated  in  the  fourth  building  from  the  corner 
occupied  by  the  Granite  Building,  and,  upon  the  destruction 
of  the  intervening  structures  and  of  the  wholesale  store  and 
other  minor  stables  to  the  north,  entered  the  Granite  Building 
through  the  openings  previously  described,  and  through  the 
court  windows. 

The  result  to  the  Granite  Building  included  a  fairly  complete 
sweep  of  fire  from  basement  to  roof,  although  on  no  floor  were 
all  combustible  materials  consumed.  The  lower  flanges  of  the 
floor  arch  tiles  were  broken  off  in  considerable  quantities  on 
the  tenth,  eleventh,  and  twelfth  floors,  this  source  of  damage 
decreasing  as  the  lower  floors  were  reached.  Only  small  sec- 
tions of  the  column  protections  were  down  or  broken,  but  the 
partitions  were  generally  weak  and  unstable  owing  to  the  burn- 
ing out  of  the  wooden  top  strip.  All  marble  wainscoting  and 
stair  treads  were  destroyed,  but  slate  treads  in  the  upper  stories 
were  in  good  condition. 

Altogether  the  lesson  to  be  drawn  from  this  fire  is  similar  to 
that  offered  by  the  Home  Life  Building  previously  described, 
except  that  the  conditions  were  greatly  aggravated  by  the  un- 
protected communicating  openings.  "From  the  fire-protection 
point  of  view  these  openings  were  almost  inexcusable  under  any 
circumstances,  and,  when  unclosed  by  doors,  shutters,  or  any 
device  for  checking  fire,  as  was  the  case  here,  their  existence 
falls  little  short  of  criminal  carelessness."* 

San  Francisco  Conflagration.  —  The  conflagration  which 
destroyed  the  larger  part  of  San  Francisco,  April  18  to  21,  1906, 
constituted  the  greatest  fire  in  the  history  of  the  world.  The 
devastated  area  comprised  4.05  square  miles,  or  2593  acres  of 
closely  built  city  property,  of  which,  314  acres  comprised  the 
congested  area  of  the  city.  Four  hundred  and  ninety  blocks  of 
buildings  were  entirely  destroyed,  and  thirty-two  blocks  par- 
tially destroyed.  A  comparison  of  the  areas  destroyed  in  the 
Chicago,  Baltimore,  and  San  Francisco  conflagrations  is  shown 

*  Engineering  News,  March  10,  1904. 


FIRES    IN    FIRE-RESISTING    BUILDINGS  179 

in  Fig.  1.  The  property  loss  in  the  San  Francisco  fire  was  about 
$500,000,000,  about  one-half  of  which  was  covered  by  insurance. 
Eight  hundred  lives  are  also  believed  to  have  been  lost  through 
the  earthquake  and  fire,  although  the  official  count  was  less. 

Condition  of  City  from  Fire  Protection  Standpoint.  — 
"San  Francisco  was  little  prepared  to  fight  a  conflagration 
under  the  existing  conditions.  Ever  since  the  six  devastating 
fires  of  the  period  from  1849  to  1852  the  people  had  evidently 
relied  on  the  excellence  of  the  fire  department  (subsequently 
organized),  the  damp  atmosphere,  and  the  tradition  that  red- 
wood, which  composed  the  exterior  of  90  per  cent,  of  the  struc- 
tures, would  not  burn.  Dwellings  were  not  protected  against 
fire  either  from  within  or  without,  and  the  same  may  be  said 
of  most  of  the  boarding  houses  and  even  of  some  of  the  public 
hotels.  There  were  few  chemical  extinguishers,  private  water 
supplies  or  other  fire  apparatus  in  existence.  In  the  congested 
business  district,  buildings  that  had  ample  modern  means  of 
fire  prevention  within,  or  protection  against  fire  from  without, 
were  the  exception  rather  than  the  rule.  Few  buildings  had 
metal  shutters,  wire  glass  windows,  sprinkler  systems  (interior 
or  exterior)  or  private  wells,  tanks  or  pumps.  Some  buildings, 
where  these  preventives  were  installed,  were  saved,  although 
surrounded  by  fire.7'* 

In  fact,  conditions  in  San  Francisco  were  so  bad  from  the 
standpoint  of  fire  protection,  that  the  report  on  that  city  issued 
by  the  Committee  of  Twenty  of  the  National  Board  of  Fire 
Underwriters,  in  October,  1905,  some  six  months  before  the 
fire,  summed  up  the  conflagration  hazard  in  the  following 
prophetic  words: 

Conflagration  Hazard.  —  Potential  Hazard.  —  In  view  of  the 
exceptionally  large  areas,  great  heights,  numerous  unprotected 
openings,  general  absence  of  fire  breaks  or  stops,  highly  combus- 
tible nature  of  the  buildings,  many  of  which  have  sheathed  walls 
and  ceilings,  frequency  of  light  wells  and  the  presence  of  inter- 
spersed frame  buildings,  the  potential  hazard  is  very  severe. 
Probability  Feature.  —  The  above  features  combined  with  the 
almost  total  lack  of  sprinklers  and  absence  of  modern  protective 
devices  generally,  numerous  and  mutually  aggravating  confla- 
gration breeders,  high  winds  and  comparatively  narrow  streets, 
make  the  probability  feature  alarmingly  severe. 

*  See  Prof.  Frank  Soule",  in  Bulletin  No.  324  of  United  States  Geological 
Survey,  "The  San  Francisco  Earthquake  and  Fire,"  p.  138. 


180         FIRE    PREVENTION    AND    FIRE    PROTECTION 

Summary.  —  While  two  of  the  five  sections  into  which  the 
congested  value  district  is  divided  involve  only  a  mild  confla- 
gration hazard  within  their  own  limits,  they  are  badly  exposed 
by  the  others  in  which  all  elements  of  the  conflagration  hazard 
are  present  to  a  marked  degree.  Not  only  is  the  hazard  extreme 
within  the  congested  value  district,  but  it  is  augmented  by  the 
presence  of  a  compact  surrounding  great-height,  large-area  frame 
residence  district,  itself  unmanageable  from  a  fire-fighting  stand- 
point by  reason  of  adverse  conditions  introduced  by  the  topog- 
raphy. In  fact,  San  Francisco  has  violated  all  underwriting 
traditions  and  precedent  by  not  burning  up.  That  it  has  not 
done  so  is  largely  due  to  the  vigilance  of  the  fire  department, 
which  cannot  be  relied  upon  indefinitely  to  stave  off  the  inevitable. 

Statistics  of  Buildings  Burned.  —  The  number  of  buildings 
within  the  burned  area  was  estimated  at  20,000.  Of  these  there 
survived  in  a  partly  habitable  condition: 

(1)  Three  groups,  i.e.,  a  hilltop  group  of  detached  dwellings 
on  Russian  Hill,  a  group  of  warehouses  at  the  foot  of  Telegraph 
Hill,  and  a  mercantile  group  near  the  custom  house. 

(2)  A  factory  plant,  i.e.,  the  Western  Electric  Company's 
branch,  the  California  Electric  Company. 

(3)  Three  United  States  Government  buildings,  i.e.,   the 
Mint,  the  Postoffice,  and  the  Appraisers'  Building;   also  part  of 
the  Hall  of  Justice. 

(4)  Two  fireproof  office  buildings,  i.e.,   the  Hay  ward   or 
Kohl  Building,  with  a  three-story  building  adjoining,  and  the 
Atlas  Building,  with  a  two-story  building  adjoining. 

There  also  survived,  in  uninhabitable  condition,  but  gen- 
erally with  structural  integrity,  all  but  four  of  the  other  fireproof 
buildings,  namely  38,  of  which  15  were  mercantile  and  the  rest 
of  office  or  dwelling  occupancy ;  also  six  steel  frames  of  unfinished 
fireproof  buildings.  There  was  but  one  fireproof  building  of 
over  two  stories  in  height  totally  destroyed,  the  Altamont  Apart- 
ment House,  which  was  dynamited. 

Within  the  burned  district  not  only  did  all  frame  buildings 
succumb,  but  also  all  brick  buildings  having  wooden  floor  beams 
succumbed,  whether  their  construction  was  good,  bad  or  in- 
different of  its  kind,  and  with  more  or  less  complete  structural 
rum  in  nearly  every  case  except  that  of  the  Palace  Hotel.* 

Of  the  54  fire-resisting  buildings  partially  or  wholly  destroyed, 

8  were  of  steel  frame  and  terra-cotta  floor  arches, 

29  were  of  steel  frame  and  reinforced  concrete  floor  arches, 
2  were  of  reinforced  concrete  frame  and  floors, 

9  were  of  brick  walls  and  fire-resisting  floor  construction, 
6  were  uncompleted  and  unenclosed  steel  frames. 

*  Report  by  Mr.  S.  A.  Reed,  Consulting  Engineer,  to  National  Board  of 
Fire  Underwriters. 


FIRES   IN    FIRE-RESISTING    BUILDINGS  181 

Damage  to  Fire-resisting  Buildings.  —  It  is  impossible, 
within  the  scope  of  this  handbook,  to  give  detailed  descriptions 
of  the  fire  damage  which  resulted  to  the  fifty-four  fire-resisting 
buildings  mentioned  in  the  last  paragraph.  A  careful  study  of 
nearly  all  of  them  will  well  repay  the  attention  of  architects  or 
fire  protectionists.  Numerous  articles  and  reports,  and  even 
several  good-sized  volumes  have  been  written,  principally  about 
the  so-called  " fireproof"  buildings.  The  following  are  worthy 
of  especial  attention: 

"The  San  Francisco  Earthquake  and  Fire,"  by  Grove  Karl 
Gilbert,  Richard  Lewis  Humphrey,  John  Stephen  Sewell  and 
Frank  Soule,  issued  as  Bulletin  No.  324  of  the  Department  of 
Interior  of  the  United  States  Geological  Survey. 

Report  to  the  National  Board  of  Fire  Underwriters,  by  Mr.  S. 
A.  Reed,  Consulting  Engineer  to  the  Committee  of  Twenty. 

Report  of  a  general  committee  and  of  six  special  committees 
of  the  San  Francisco  Association  of  Members  of  the  American 
Society  of  Civil  Engineers  with  discussions,  Transactions  Am. 
Soc.  C.  E.,  Vol.  LIX,  page  208. 

"The  San  Francisco  Earthquake  and  Fire,"  by  A.  L.  A. 
Himmelwright,  C.  E.,  published  by  the  Roebling  Construction 
Company. 

"Trial  by  Fire  at  San  Francisco,"  published  by  the  National 
Fireproofing  Company. 

A  careful  perusal  of  these  and  other  less  noteworthy  reports 
will  reveal  a  wide  divergence  of  opinion  regarding  many  phases 
of  the  fire  damage  done  to  buildings,  particularly  as  regards 
the  old  and  vexed  question  of  concrete  vs.  terra-cotta  con- 
struction. This  subject  will  be  discussed  at  some  length  in 
later  chapters,  but  it  does  not  affect  at  all  many  broad  deduc- 
tions from  the  San  Francisco  fire,  upon  which  nearly  all  of  those 
who  have  carefully  investigated  the  subject  have  generally 
agreed. 

General  Deductions  from  San  Francisco  Fire.  —  The 
great  lessons  taught  by  this  fire  were  precisely  those  brought 
out  by  the  Baltimore  experience,  namely,  the  necessity  of  pro- 
tection against  exposure  hazard  and  of  auxiliary  equipment  or 
protective  devices  for  coping  with  fire,  and  the  imperative  need 
of  using  and  applying  fire-resisting  materials  in  more  mass, 
with  better  workmanship,  and  with  more  care  as  to  intelligent 
application. 


182         FIRE    PREVENTION    AND    FIRE    PROTECTION 

Mr.  Reed,  in  the  report  before  mentioned,  gives  the  following 
as  his  conclusions: 

The  importance  of  both  front-  as  well  as  rear-  and  side- win- 
dow protection,  fire-resistant  if  possible,  but  at  any  rate  fire- 
retardant. 

The  importance  of  encouraging  individual  protection  by 
occupants  of  buildings. 

The  importance  of  fire-resisting  roofs,  roof  structures  and 
of  well-protected  skylights. 

The  importance  of  ample  water  supply  and  pressure. 

The  importance  to  the  fire  department  of  a  large  reserve  of 
hose,  and  of  apparatus  of  longer  range  and  heavier  caliber.  The 
latter  need  not  be  limited  by  the  same  conditions  of  quick  re- 
sponse to  alarms  as  ordinary  apparatus. 

Restriction  upon  the  use  of  explosives  in  conflagrations. 

In  hollow  tile  for  fireproof  building,  the  importance  of  im- 
proved sections  giving  greater  strength  to  lower  webs. 

The  importance  in  partitions  of  a  better  bracing  of  tile,  and 
the  importance  of  fire-ret ardant  transoms  as  well  as  doors. 

The  importance  of  better  protection  to  the  steel  frame  in 
roof  attics. 

The  importance  of  good  bricklaying  and  mortar  with 
cement  instead  of  lime. 

The  encouraging  possibilities  of  reinforced  concrete,  and 
the  importance  of  good  engineering  in  its  installation. 

The  necessity  of  adopting  standards  for  column  protection. 

It  has  been  considered  a  reasonable  assumption  that  a  con- 
flagration destroying  the  business  part  of  a  city  would  still  prob- 
ably be  checked  in  the  brick  dwelling  quarter.  The  experience 
of  San  Francisco,  whose  dwelling  district  was  almost  entirely 
frame,  cannot  be  considered  a  ground  for  changing  this  view. 

Prof.  Frank  Soule  derives  final  conclusions  as  follows: 

The  lessons  taught  by  the  great  fires  of  Boston,  Chicago 
and  Baltimore  have  been  verified  by  San  Francisco's  experience. 

Fireproofing  should  be  of  the  most  perfect  type,  and  no 
reasonable  expense  should  be  spared  in  its  installation. 

Roofs,  roof  appurtenances  and  skylights  should  be  given 
ample  protection  against  fires  from  without.  A  great  excess  of 
fire  hose  and  apparatus,  beyond  ordinary  needs,  should  be 
available.  A  strong  bond  for  fireproof  tiling,  etc.,  for  both  girder 
and  column  protection,  is  essential.  Protection  for  front  win- 
dows, as  well  as  for  side  and  rear  ones,  is  of  vital  importance. 
Good  protection  for  steel  frames  and  steel  roof  trusses  in  attics 
or  other  exposed  or  unusual  places  should  be  provided.  Liberal 
use  should  be  made  of  fire  retardant  in  windows,  doors,  transoms, 
etc.  Wise  and  liberal  use  of  concrete  and  reinforced  concrete 
for  girder  and  column  fireproofing  has  proved  its  saving  quality. 


FIRES   IN   FIRE-RESISTING   BUILDINGS  183 

Interior  fire  protection  and  prevention  by  wells,  pumps,  sprink- 
lers and  water  tanks  vastly  lessen  fire  risk. 

Parker  Building  Fire.  —  The  burning  of  the  twelve-story 
Parker  Building  at  Fourth  avenue  and  19th  street,  New  York 
City,  on  the  night  of  January  10,  1908,  is  of  particular  interest 
in  as  much  as  this  constitutes  the  first  case  on  record  where  a 
so-called  " fireproof"  building  has  suffered  such  great  damage 
from  fire  originating  on  the  premises.  That  a  supposedly  fire- 
resisting  building,  in  the  largest  city  of  the  United  States,  could, 
in  spite  of  the  protection  afforded  by  an  efficient  fire  department, 
suffer  a  loss  to  the  structure  of  sixty-five  per  cent,  of  its  sound 
value  and  a  practically  complete  loss  of  contents,  shows  that 
either 

1,  the  building  was  not  fire-resisting,  or 

2,  if   fire-resisting,    necessary   auxiliary   equipment   was   not 
installed  for  the  detection  and  fighting  of  fire,  or 

3,  the  fire  department  was  not  as  efficient  as  should  reasonably 
be  expected. 

As  a  matter  of  fact,  all  three  of  these  conditions  contributed 
to  the  result. 

The  Building,  built  in  1900,  was  originally  designed  as  a  mer- 
cantile structure.  The  street  walls  were  limestone  in  two  stories, 
above  that  of  pressed  brick,  with  terra-cotta  sills  and  lintels. 
Above  the  second  floor  the  walls  were  supported,  story  by  story, 
by  the  spandrel  beams.  Cast-iron  columns  were  used  through- 
out (except  in  roof  houses),  round  for  interior,  and  square  for 
wall  columns,  varying  in  size  from  15  by  2  inches  in  basement 
to  8  by  |  inches  in  top  story,  standard  brackets,  lugs  and  con- 
nections throughout.  The  floor  framing  consisted  of  15-inch 
I-beam  girders  running  east  and  west  between  the  columns, 
and  12- inch  I  floor  beams  running  north  and  south.  Floor 
arches  were  8-inch  semi-porous  side-construction  terra-cotta, 
projecting  1J  inches  below  the  beams.  Hence  the  effective 
depth  of  the  arches  .was  but  6|  inches,  over  which  was  an  8|-inch 
loose-cinder  concrete  filling,  adding  much  to  the  dead  load, 
but  contributing  little  or  nothing  to  the  strength. 

Investigation  of  the  strength  of  the  various  arches  used 
develops  the  fact  that  they  were  extremely  weak  for  the  spans 
employed.  The  allowable  load-carrying  capacities  of  the  arches 
on  the  7-  and  6-foot  spans  were  5  and  35  pounds  per  square  foot, 
respectively,  over  and  above  the  dead  loads;  in  other  words, 


184          FIRE   PREVENTION   AND    FIRE   PROTECTION 

any  live  loads  averaging  in  excess  of  these,  on  the  floor,  would 
introduce  stresses  in  excess  of  those  allowable  by  good  practice. 
This  is  also  true  to  a  lesser  extent  in  the  case  of  the  4J-  and  5-foot 
spans. 

These  shallow  arches  were  not  only  too  weak  for  the  spans, 
but  their  live-load  capacity  was  considerably  reduced  by  the 
unusual  amount  of  cinder  fill.  At  the  large  roof  house  the  dead 
load  alone  exceeded  the  allowable  safe  live  load,  the  cinder  fill 
at  this  point  being  in  excess  of  30  inches.* 


The  lower  flanges  of  girders  were  unprotected  save  by  plaster. 
Soffits  of  floor  beams  were  protected  by  1J-  to  IJ-inch  solid 
flange  tile  held  in  place  by  lips  on  skewbacks.  Column  pro- 
tection consisted  of  a  2-inch  covering  of  porous  terra-cotta, 
the  blocks  having  a  1-inch  thick  shell  with  1-inch  ribs  or  flanges. 
Column  coverings  were  generally  cut  to  accommodate  electric 
conduits  (see  Fig.  55).  Partitions  enclosing  stair  and  elevator 
halls  and  corridors  were  of  3-inch  terra-cotta  blocks,  but  with 
wood  bucks,  wood  doors,  and  wood  framing  and  casings  at 
large  window  areas. 

Spread  of  Fire.  —  Before  the  arrival  of  the  fire  department, 
the  fire  gained  tremendous  headway  for  several  reasons.  No 
equipment  existed  for  the  automatic  detection  of  fire;  the  fire 
was  not  discovered  promptly  by  watchman  or  tenants;  unpro- 
tected stair  and  elevator  shafts  acted  as  flues,  and  caused  the 
communication  of  fire  from  floor  to  floor;  the  corridor  partitions 
were  totally  unsuited  to  resist  fire,  in  fact  they  contributed  no 
small  amount  of  fuel;  and  the  building  did  not  contain  those 
auxiliary  aids  to  control  fire  once  started,  which  should  have 
been  present  in  a  building  of  this  character  and  tenantry.  The 
fire  was  soon  beyond  all  control. 

The  writer  happened  to  be  at  the  site  of  the  fire  in  question 
when  the  alarm  was  turned  in,  and  before  a  single  engine  had 
arrived,  and  when  flames  had  broken  through  only  a  few  of  the 
fifth-story  windows  on  19th  street,  the  fire  could  be  plainly  seen 
through  the  closed  iron  shutters  on  the  east  wall,  working  up 
rapidly  from  story  to  story  through  the  open  stair  well  at  that 
location,  until,  as  the  upper  floor  was  reached,  the  flames  spread 
out  umbrella-like,  enveloping  the  upper  story,  and  then  worked 
downwards  again  through  other  shafts. f 

*  Report  of  Mr.  W,  C.  Robinson  to  New  York  Board  of  Fire  Underwriters, 
t  See  "Fire  Prevention  in  High  Buildings.     The  Need  of  Auxiliary  Equip- 
ment," by  J.  K.  Freitag,  in  Engineering  Magazine,  February,  1908. 


FIRES    IN    FIRE-RESISTING    BUILDINGS  185 

The  Fire  Damage.  —  About  an  hour  and  a  half  after  the  start 
of  the  fire,  when  the  building  was  burning  fiercely  from  the  fourth 
story  up,  all  floors  of  a  section  approximately  40  by  24  feet 
suddenly  collapsed,  killing  three  firemen,  and  seriously  injuring 
fourteen  others.  Another  collapse  of  a  portion  of  the  twelfth 
floor,  roof  and  roof  house  occurred  later.  The  first  and  far 
more  serious  collapse  was  due  to  the  failure  of  the  cast-iron 
columns,  owing  to  the  giving  way  of  the  protective  coverings. 
About  one-fourth  of  all  column  coverings,  although  mostly  in 
position,  was  badly  damaged,  largely  due  to  the  expansion  of 
the  tile  itself,  the  lack  of  proper  application,  and  bonding,  and 
also  to  the  distortion  of  the  metal  conduits  cut  into  the  tile 
coverings.  The  second  great  item  of  structural  damage  was 
the  failure  of  many  floor  arches.  About  22|  per  cent,  of  the 
total  number  either  fell,  sagged  or  were  badly  cracked,  principally 
because  unable  to  withstand  the  impact  of  falling  debris.  Par- 
titions generally  collapsed. 

The  sound  value  of  the  building  was  $562,743,  of  which  the 
loss  value  was  $369,000  or  65.5  per  cent. 

The  Chelsea  Conflagration  occurred  on  Sunday,  April  12, 
1908,  ending  in  the  destruction  of  approximately  one-half  the 
improved  area  of  the  city  of  Chelsea,  Mass.  About  3500 
buildings  were  burned,  covering  an  area  of  nearly  275  acres. 

"  Students  of  fire-protection  engineering  will  find  in  the  Chelsea 
fire  little  of  scientific  interest,  but  municipal  authorities  might 
profit  by  the  lessons  it  teaches."* 

Chelsea  cannot  be  considered  blameless  for  this  conflagra- 
tion. The  officials  fully  realized  the  conditions.  Both  water 
board  and  fire  department  had  asked  for  improvements  but  the 
aldermen  refused  to  grant  appropriations.  Fire  protection  that 
is  originally  ample  should  keep  pace  with  changed  conditions  in 
cities  and  almost  invariably  cities  fail  to  recognize  these  changed 
conditions.  In  the  case  of  Chelsea,  however,  it  proved  to  be 
not  so  much  defective  water  works  and  fire  department  as 
inadequate  building  laws  poorly  enforced,  and  the  admittance 
of  an  irresponsible  foreign  population  supposed  to  be  favorably 
inclined  to  incendiarism. 

Conclusions.  —  The  most  notable  facts  which  this  fire 
emphasizes  are  as  follows: 

1.   The  dangerous  nature  of  pitch  or  mansarol  shingle  roofs, 

*  Extracts  from  report  on  the  Chelsea  conflagration,  by  Gorham  Dana,  in 
National  Fire  Protection  Association  "Quarterly,"  July,  1908. 


186         FIRE    PREVENTION    AND    FIRE    PROTECTION 

frame  porches,  piazzas  and  accessory  woodwork  in  spreading  a 
conflagration. 

2.  The  complete  failure  of  any  roof  supported  by  unpro- 
tected steel  or  iron  to  withstand  any  but  the  smallest  fire. 

3.  The  need  of  good  window  protection  where  the  sweep  of 
the  flames  is  parallel  to  division  walls  and  the  necessity  of  blank 
walls  or  properly  protected  window  openings  and  parapet  walls 
at  right  angles  to  prevailing  winds. 

4.  The  vulnerability  of  any  ordinary  buildings  to  sparks 
and  embers,  provided  the  bombardment  be  long  enough,  even 
though  the  space  separating  them  from  the  burning  buildings  is 
great. 

5.  The  slight  value  of  streets  of  ordinary  width  in  holding 
a  fire  when  there  is  strong  wind  blowing  and  the  fighting  force 
is  scattered. 

6.  That  the  safest  way  to  store  oil  in  large  quantities  is  in 
well-made  boiler  iron-riveted  tanks  having  covers  of  the  same 
material  with  large  automatic  relief  valve,  all  well  supported  on 
brick  or  concrete  piers. 

7.  That  municipalities  cannot  violate  the  laws  of  good  con- 
struction and  fire  protection  without  inviting  conflagration. 

8.  That  the  Metropolitan  water-works  system  is  shown  to 
be  exceedingly  valuable  for  cities  which  it  serves  as  it  successfully 
withstood  the  extraordinary  draught  caused  by  this  conflagra- 
tion, although  the  Chelsea  mains  were  not  adequate  in  size  nor 
properly  gridironed. 

9.  That  more  cooperation  is  needed  between  city  officials 
and  insurance  interests  in  regard  to  protection  against  fire.* 

The  Asch  Building  Fire,  possibly  better  known  as  the 
" Triangle  Waist  Company"  fire,  occurred  on  March  25,  1911, 
with  an  attendant  loss  of  life  which  greatly  shocked  the  civilized 
world.  To  the  experiences  of  the  Windsor  Hotel,  the  Collin- 
wood  School  and  the  Iroquois  Theater  is  now  to  be  added  that 
of  a  factory  or  loft  building  fire,  in  which  the  loss  of  life  among 
the  employees  working  eight,  nine  or  ten  stories  above  the 
ground,  totaled  145,  most  of  them  women  and  girls.  The 
disaster  was  especially  analogous  to  the  Iroquois  Theater  fire, 
in  that  both  buildings  were  "  fire-resisting  "  as  far  as  the  structures 
themselves  were  concerned,  while  both  disregarded,  in  glaring 
deficiencies,  the  safety  of  the  human  lives  contained  therein. 
Unless  past  lessons  are  heeded  it  is  only  a  question  of  time  until 
the  department  store  and  the  office  building  add  these  re- 
spective types  of  structures  to  the  pyres  of  modern  civilization. 

*  Extracts  from  report  on  the  Chelsea  conflagration,  by  Gorham  Dana,  in 
National  Fire  Protection  Association  "  Quarterly,"  July,  1908. 


FIRES    IN    FIRE-RESISTING    BUILDINGS  187 


FIG.  4.1.  —  Asch  Building  Fire,  New  York. 

"Note  the  ineffectiveness  of  the  powerful  hose  stream  directed  from  the 
street  toward  the  window  on  the  10th  floor.  The  portion  of  a  stream  shown 
at  the  extreme  left  is  from  a  water  tower.  This  enters  the  10th  floor  at  a 
somewhat  more  effective  angle,  but  still  ineffective  a  few  feet  back  from  the 
window.  The  two  small  streams  entering  the  10th  floor,  as  shown  in  the  upper 
right  hand  corner  of  the  picture,  are  directed  from  a  building  across  a  fifty-foot 
street." 


188         FIRE    PREVENTION    AND    FIRE    PROTECTION 

The  Building  *  is  a  ten-story  loft  building,  built  in  1900-1901, 
situated  at  the  coiner  of  Washington  place  and  Greene  street, 
New  York  City  (see  Fig.  41).  The  lot  area  is  practically  100  feet 
square  which,  less  open  courts  on  two  sides,  leaves  typical  floor 
areas  of  about  9000  square  feet.  The  construction  is  as  usual 
in  such  buildings  in  New  York,  viz.,  cast-iron  protected  columns, 
steel  girders  and  floor  beams,  protected  by  hollow  tile  arches. 

Fire-resisting  Equipment  included  automatic  fire  alarms  in 
the  form  of  thermostats,  fire  pails,  a  4-inch  standpipe  in  each 
stair  shaft  (supplied  by  a  2000-gallon  tank  on  roof) ,  with  50  feet 
of  hose  on  each  floor,  and  perforated  pipes  in  basement  and  sub- 
basement. 

The  Damage  to  Building  was  comparatively  slight.  The 
upper  three  floors  were  completely  burned  out,  -but  the  struc- 
tural damage  was  small.  Weaknesses  of  design  or  construction 
were  made  manifest,  however,  as  follows: 

1.  Non-waterproof  floors  and  floor  arches  resulted  in  great 
water  damage  to  stock  on  the  floors  below  the  fire. 

2.  Wire  glass  was  shown  to  be  unreliable  for  panels  of  stair 
or  elevator  doors  under  severe  conditions. 

3.  The  danger  of  auto-exposure,   or  the  communication  of 
fire  from  story  to  story  by  means  of  the  windows  in  exterior 
walls,  was  again  emphasized. 

Occupancy.  —  The  principal  interest  in  connection  with  this 
fire  centers  in  the  stories  (eighth,  ninth,  and  tenth)  occupied  by 
the  Triangle  Waist  Company,  and  the  conditions  found  therein. 

On  the  eighth  floor  there  were  five  unbroken  rows  of  4-foot 
tables,  each  containing  a  double  row  of  sewing  machines  and 
shirt  waists  in  process  of  manufacture.  These  tables  extended 
from  the  Washington  place  front  (south  wall)  to  within  18  feet 
of  the  north  side  of  the  building.  This  latter  space  was  partially 
filled  with  stock,  principally  on  tables.  An  isle  space  was  also 
left  running  east  and  west  along  the  north  side.  The  space 
along  the  east  wall  contained  the  cutting  tables.  Approximately 
275  operators  were  on  this  floor. 

On  the  ninth  floor  there  were  eight  unbroken  rows  of  4-foot 
tables  each  containing  double  rows  of  sewing  machines  and  shirt 
waists  in  process  of  manufacture.  These  tables  extended  from 
the  Washington  place  front  (south  wall)  to  within  10  feet  of  the 

*  For  a  more  complete  description  of  the  building,  see  report  issued  by  New 
York  Board  of  Fire  Underwriters  (Mr.  F.  J.  T.  Stewart,  Superintendent),  from 
which  the  following  quotations  are  taken. 


FIRES   IN    FIRE-RESISTING    BUILDINGS 


189 


north  side  of  the  building  (see  Fig.  42).  This  latter  space  at  the 
north  side  was  partially  filled  with  stock,  and  also  contained  an 
aisle  extending  east  and  west  along  the  north  side.  Approxi- 
mately 300  operators  were  on  this  floor.  There  were  no  aisles 
running  east  and  west  at  the  south  side  of  the  eighth  and  ninth 
floors,  the  sewing-machine  tables  extending  close  up  to  the  wall. 
The  space  between  the  tables  was  approximately  4  feet  wide  and 
contained  two  rows  of  chairs  back  to  back  for  the  operators. 


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GREENE  ST. 

FIG.  42.  —  Floor  Plan  of  Asch  Building. 

This  space  also  contained  baskets  and  other  receptacles  for  the 
goods  in  process  of -manufacture.  The  only  convenient  way  for 
the  operators  next  to  the  south  wall  to  reach  the  stairs  and  ele- 
vators at  the  southwest  corner,  was  to  walk  the  entire  length  of 
the  crowded  space  between  the  tables  to  the  north  side  and  then 
use  the  aisles  which  extended  along  the  north  and  west  sides  of 
the  building. 

On  the  tenth  floor  very  little  work  was  done,  it  being  used 
principally  for  the  office,  show  and  stock  rooms,  and  shipping 
department.  About  30  hands  were  employed  on  this  floor 


190        FIRE   PREVENTION   AND   FIRE   PROTECTION 

pressing  shirt  waists  by  gas-heated  irons.     Approximately  60 
employees  were  on  this  floor. 

These  conditions  were  commented  on  editorially  by  the 
Engineering  News  (March  30,  1911),  as  follows: 

The  public  does  not  permit  powder  magazines  to  be  located 
in  the  heart  of  a  city  or  where  many  lives  would  be  endangered. 
But  it  does  permit  great  aggregations  of  easily  inflammable  com- 
bustibles to  be  placed  anywhere,  even  in  a  tall  building  crowded 
with  workers.  It  tacitly  approves  wholesale  gambling  against 
the  chances  of  a  fire  outbreak.  Neither  law  nor  administrative 
practice  nor  public  sentiment  decrees  anything  to  prevent  fac- 
tories, warerooms  and  stores  from  being  so  located  and  grouped 
and  so  packed  with  human  beings  that  every  available  resource 
of  rescue  and  fire-fighting  work  is  powerless  to  help  when  the 
fire  chance  wins. 

The  Harris  and  Blanck  shirtwaist  factory  was  inspected  by 
the  State  factory  inspectors  within  two  months  and  reported 
to  be  substantially  up  to  the  law.  The  building  was  inspected 
by  the  city  Fire  Department  six  months  ago  and  reported  good. 
The  municipal  Bureau  of  Buildings  had  approved  of  its  construc- 
tion and,  while  some  departures  from  the  letter  of  the  law  are 
admitted,  yet  in  the  important  points  the  design  and  construc- 
tion complied  with  the  requirements.  No  law  stepped  in  to  say 
that  three  superimposed  quarter-acres  filled  with  cuttings  of 
flimsy  fabric  contain  a  grave  fire  risk;  not  even  to  the  extent  of 
saying  that  here,  if  anywhere,  the  protective  aid  of  automatic 
sprinklers  is  needed.  No  law  said  that  700  persons  on  the  three 
floors,  ranged  in  among  tables,  sewing  machines,  boxes  and  piles 
of  goods,  are  too  many  for  safe  and  rapid  exit;  or  that  subdivision 
into  smaller  compartments  is  needed  to  reduce  the  risk.  The 
gravity  of  the  conditions  is  not  fairly  measured  by  the  death-roll. 
Had  there  been  seven  floors  above  the  shirt-waist  factory  as 
there  were  seven  below,  not  merely  three  floors  but  ten  would 
have  furnished  victims. 

The  Fire  started  about  4.42  P.M.,  on  the  eighth  floor,  near  the 
northeast  corner  of  building.  The  cause  is  believed  to  have 
been  a  match  or  cigarette,  carelessly  thrown  on  cuttings  of 
waist  materials  lying  on  the  floor.  Unsuccessful  efforts  were 
made  to  extinguish  the  fire  by  means  of  the  fire  pails,  but  the 
exceptionally  quick  spread  of  the  fire  was  undoubtedly  due  to 
the  large  quantities  of  inflammable  stock  in  process  of  manu- 
facture. 

As  to  the  results,  suffice  it  to  say  that  practically  all  of  the 
employees  on  the  eighth  floor  escaped  by  means  of  stairways 
and  elevators,  as  did  nearly  all  of  those  on  the  tenth  floor  by 
means  of  the  stairs  to  roof,  and  thence  to  the  roofs  of  adjoining 


FIRES   IN   FIRE-RESISTING   BUILDINGS  191 

buildings.     Practically  the  entire  loss  of  life  was  confined  to 
those  employed  on  the  ninth  floor. 

Summary.  —  This  fire,  on  account  of  the  great  sacrifice  of 
life,  has  attracted  popular  interest  to  the  usual  neglect  of  three 
fundamental  features  of  fire  prevention  and  fire  protection  which 
ordinarily  impress  only  the  insurance  companies  and  the  owners 
of  the  large  property  values  destroyed.  This  fire,  by  the  cir- 
cumstances attending  its  origin,  spread,  and  destruction  of  life, 
forcibly  illustrates: 

First:  The  prevalent  neglect  of  ordinary  precautions  to 
avoid  the  outbreak  of  fires  due  to  readily  preventable  causes. 

Second:  The  necessity  of  adequate  facilities,  particularly 
automatic  sprinklers,  to  extinguish  fires  in  their  incipiency,  es- 
pecially where  the  nature  of  the  work  done  and  materials  used 
may  readily  cause  fires  and  rapidly  spread  them. 

Third:  The  importance  of  fire  towers  suitable  for  the  prompt 
escape  of  the  occupants  and  likewise  to  afford  the  Fire  Depart- 
ment a  safe  station  from  which  to  efficiently  fight  fires  at  close 
range.  Note  that  the  powerful  stream  directed  from  the  street 
toward  the  tenth  story  (as  shown  in  Fig.  41)  is  practically  vertical 
and  cannot  possibly  reach  a  fire  on  the  inside  even  a  few  feet 
back  from  the  windows. 

Recommendations.  —  (1)  A  fire  drill  and  private  fire  depart- 
ment should  be  organized  among  the  employees  of  all  factories 
to  prevent  panic  and  extinguish  fires.  "The  plan  of  organization 
outlined  in  the  recommendations  of  the  National  Fire  Protection 
Association  should  be  used  as  a  guide  for  this  purpose. 

(2)  All  stairways  or  a  sufficient  number  of  them  should  be 
located  in  fireproof  shafts  having  no  communication  with  the 
building  except  indirectly  by  way  of  an.  open-air  balcony  or 
vestibule  at  each  floor.     Hose  connections  attached  to  stand- 
pipes  should  be  located  on  each  floor  in  the  stair  towers  for  public 
or  private  fire-department  use. 

(3)  Stairs,  if  any,  inside  the  building,  and  elevators  should 
be  enclosed  in  shafts  of  masonry  and  have  fire  doors  at  all  com- 
munications to  floors. 

(4)  The  provisions  ordinarily  necessary  for  fire-escape  towers 
might  be  somewhat  modified  in  buildings  equipped  with  a  system 
of  automatic  sprinklers  installed  according  to  the  standards  of 
the  National  Fire  Protection  Association. 

(5)  Present  buildings  with  inadequate  fire  escapes  should 
be  provided  with  -  automatic  sprinklers  and   (or)   smoke-proof 
stair  towers,  but  additional  outside  fire  escapes  passing  in  front 
of  or  near  the  windows  should  be  discouraged. 

(6)  No  factory  building  containing  inflammable  goods  in 
process  of  manufacture,  or  employing  in  excess  of  a  limited  num- 
ber of  operatives  (limit  to  be  definitely  fixed),  should  be  without 
automatic  sprinklers.     No  building  over  60  feet  high  and  con- 
taining inflammable   goods,    where   a   considerable   number  of 
people  are  employed,  should  be  without  automatic  sprinklers. 


192         FIRE   PREVENTION   AND   FIRE   PROTECTION 

(7)  Automatic  sprinklers  should  be  installed  in  high  build- 
ings to  control  a  fire  and  thus  prevent  it  from  spreading  rapidly 
from  floor  to  floor  by  way  of  outside  windows.  The  use  of  wire 
glass  in  metal  frames  for  all  exterior  windows  would  also  retard 
such  vertical  spread  of  fire  but  not  so  effectively  as  a  complete 
equipment  of  automatic  sprinklers  throughout  the  building. 

Temperatures  Exhibited  in  Fires  and  Conflagrations.  - 

The  heat  of  a  wood  fire  is  from  800  to  1140°  F.;  charcoal  fire 
about  2200  degrees;  coal  about  2400  degrees. 

The  melting  points  of  iron  and  steel  are  from  2075  to  2228°  F. 
for  cast  iron,  and  from  2300  to  2600  degrees  for  various  grades 
of  steel. 

The  following  extracts  from  several  trustworthy  reports  on 
fires  and  conflagrations  will  serve  to  show  the  temperatures 
estimated  to  have  occurred. 

It  is  estimated  that  the  temperature  of  the  fire  (i.e.,  Balti- 
more) was  rarely  much  in  excess  of  2200°  F.,  although  in  some 
spots  it  seems  to  have  been  approximately  2800  degrees  or  more. 
According  to  various  estimates  the  most  intense  heat  in  the  fire- 
resistive  buildings  lasted  from  30  to  60  minutes,  varying  with  the 
amount  of  combustible  contents,  exposures  and  other  features. 
Cast-iron  radiators  and  typewriter  frames  were  found  in  some 
places  almost  completely  destroyed  by  oxidation,  but  had  melted 
in  a  few  cases  only.  Wire  glass  melted  in  a  number  of  instances.* 

In  the  San  Francisco  conflagration  "the  heat  was  so  intense 
that  sash  weights  and  glass  melted  and  ran  together  freely. 
In  some  places  the  edges  of  broken  cast-iron  columns  softened, 
the  tin  coating  in  piles  of  tinned  plates  volatilized,  even  in  the 
middle  of  the  piles,  and  nails  were  softened  sufficiently  to  weld 
together.  The  maximum  temperature,  lasting  for  a  few  minutes 
in  each  locality,  was  probably  2000  to  2200°  F.,  while  the  average 
temperature  did  not  exceed  1500°  F."f 

Captain  Sewell,  in  the  same  report,  states  as  follows: 

All  things  considered,  I  am  inclined  to  think  that  tempera- 
tures considerably  in  excess  of  2000°  F.  were  not  at  all  uncom- 
mon in  the  San  Francisco  fire,  although  there  were,  manifestly, 
in  the  burned  area,  places  where  no  such  temperature  was 
reached.  Very  few  office  buildings  were  subjected  to  such  in- 
tense heat,  except  here  and  there  in  individual  rooms,  where 
there  was  evidence  of  the  storage  of  records  or  other  combustible 
matter  in  large  quantities;  but  the  department  stores,  dry-goods 
stores  and  other  buildings  of  mercantile  occupancy  evidently 
suffered  from  temperatures  at  least  as  high  as  2000°  F.  In  mer- 

*  National  Fire  Protection  Association  Report  on  Baltimore  Conflagration, 
t  Mr.  Richard  L.  Humphrey,  in  United  States  Geological  Survey  Bulletin,. 
No.  324. 


FIRES   IN    FIRE-RESISTING    BUILDINGS  193 

cantile  buildings  these  high  temperatures  seemed  to  be  the  rule 
and  not  the  exception. 

In  the  Parker  Building  fire,  Mr.  Robinson  estimated  the 
maximum  temperature  to  have  been  slightly  in  excess  of  2000°  F. 

The  temperatures  rarely  exceeded  1900  degrees,  but  were 
probably  in  excess  of  1800  degrees  for  considerable  periods  in 
several  stories.  .  .  .  The  observations  -made  indicate  that  in 
buildings  of  large  area  containing  considerable  quantities  of 
combustible  material,  the  fireproofing  should  be  capable  of  with- 
standing temperatures  as  high  as  2000°  F.  for  several  hours. 

These  estimated  temperatures  should  be  compared  with  the 
temperature  requirements  called  for  by  standard  testing  stations 
as  given  in  Chapter  V. 

FIRE    LOSSES    ON    FIRE-RESISTING    BUILDINGS;    CAUSES    AND 
REMEDIES. 

Losses  on  Baltimore  Buildings.  —  The  report  which  the 
Baltimore  Committee  of  the  National  Board  of  Fire  Under- 
writers made  on  "The  Adjusted  Fire  Losses  on  the  Fireproof 
Buildings  at  Baltimore,  Md.,"  contains  some  very  interesting 
and  valuable  analyses  of  the  insurance  losses  on  these  buildings, 
showing,  particularly,  the  relative  value  of  fire-resisting  build- 
ings in  a  conflagration  as  compared  with  ordinary,  or  non-fire- 
resisting  buildings. 

The  total  valuation  of  all  classes  of  property,  both  buildings 
and  contents,  reported  to  the  insurance  companies,  amounted 
to  $37,382,426,  on  which  there  was  insurance  amounting  to 
$32,245,273,  and  on  which  the  losses  paid  amounted  to 
$29,074,358. 

Data  concerning  the  sound  value,  fire  damage  and  insurance 
loss,  were  also  tabulated  for  23  buildings  which,  in  varying 
degrees,  might  have  been  regarded  as  fire-resisting.  The  total 
valuation  of  these  23  buildings  was  $6,546,040,  on  which  the 
fire  damage  amounted  to  $3,684,062,  the  insurance  amounted 
to  $3,606,621  and  the  fire  losses  paid  amounted  to  $2,752,888. 

Furthermore,  a  special  classification  was  made  of  the  loss 
ratios,  etc.,  for  the  seven  large  so-called  fireproof  buildings  which 
passed  through  the  fire,  i.e.,  those  previously  described  in  some 
detail  in  this  chapter.  The  total  valuation  of  these  seven  build- 
ings was  $4,075,483,  on  which  the  fire  damage  amounted  to 
$2,606,127,  and  of  which  the  losses  paid  amounted  to  $1,998,585. 


194         FIRE   PREVENTION   AND   FIRE   PROTECTION 

From  these  figures,  the  ratios  of  insurance  losses  to  total 
insurance  were  found  to  be  as  follows: 

Per  cent. 

Grand  total  of  all  classes  of  property,  buildings  and  con- 
tents, loss  ratio. 90 

The  above  grand  total,  excluding  the  23  so-called  fire- 
proof buildings 92 

The  above  grand  total,  excluding  the  7  large  buildings.  .  .  90.  4 

The  twenty-three  more  or  less  fire-resisting  buildings.  ...  76.  3 

The  seven  so-called  fireproof  buildings 88. 4 

In  other  words,  the  above  figures  show  only  a  2  per  cent, 
smaller  loss  ratio  on  the  seven  large  buildings  than  that  which 
occurred  on  all  property,  and  this  showing  led  the  committee 
to  draw  the  following  conclusion:  "When  a  city  is  visited  by  a 
general  conflagration,  the  large,  high,  so-called  fireproof  build- 
ings, without  protection  at  the  exterior  windows,  and  exposed 
by  ordinary  buildings,  are  but  little  better,  from  an  insurance 
view-point,  than  other  classes  of  property." 

Losses  on  Fire-resisting  Buildings.  —  Considering  now, 
particularly,  the  losses  sustained  by  the  owners  of  the  eight 
supposedly  fire-resisting  buildings  previously  described  in  some 
detail,  we  find  the  ratio  of  losses  to  sound  values  to  be  as  follows : 

Per  cent. 

Equitable  Building 74.  3 

Herald  Building 58. 7 

Calvert  Building 57.  3 

Union  Trust  Company's  Building 61.  5 

Maryland  Trust  Company's  Building 60.  0 

Continental  Trust  Company's  Building 64.  8 

Merchants'  National  Bank  Building 64.  8 

Chesapeake  and  Potomac  Telephone  Building.  .  38.  6 

Average 60 . 0 

From  the  standpoint  of  the  owner  or  tenant,  these  buildings 
must,  then,  have  been  very  disappointing.  The  tenants  lost 
practically  everything,  and  the  owners  lost  an  average  of  60  per 
cent,  of  the  sound  value  of  their  buildings,  besides  further  losses 
in  rents  during  reconstruction.  The  question  naturally  arises, 
then,  as  to  whether  the  value  of  fire-resisting  construction,  as 
then  or  now  practiced,  is  demonstrable  from  a  commercial  stand- 
point. To  answer  this  question  requires  a  careful  analysis  of 


FIRES   IN   FIRE-RESISTING   BUILDINGS  195 

the  losses  involved,  the  causes  thereof,  and  the  possible  remedies. 
It  will,  therefore,  be  necessary  to  consider  the  following  points: 

1.  The  percentages  of  cost  of  the  various  items  of  construc- 
tion entering  into  fire-resisting  buildings. 

2.  The  usual  ratio  of  fire  damage  to  sound  value  for  the  same 
items  of  construction. 

3.  The  causes  contributing  to  fire  da'mage  in  conflagrations 
and  in  individual  buildings,  and  remedies  therefor. 

4.  The  possibility  of  reconstruction  at  reasonable  cost. 

Percentages  of  Cost  of  Items  of  Construction  in  Fire- 
resisting  Buildings.  —  "The  accompanying  table*  (seepages 
196  to  199),  showing  how  the  cost  of  fireproof  buildings  is 
divided  among  the  various  items  of  construction,  has  been 
prepared  from  data  furnished  by  architects  and  builders  in  the 
principal  cities.  As  the  analysis  of  the  cost  of  construction  was 
not  uniform  for  all  data  received,  some  difficulty  was  experienced 
in  an  attempt  to  show  a  complete  comparison.  Thus,  in  some 
cases,  the  cost  of  foundations  has  not  been  given,  and  is  probably 
included  largely  under  mason  work.  The  comparison  is,  how- 
ever, practically  complete  in  most  cases,  as  far  as  the  five  general 
subdivisions  are  concerned,  and  should  be  of  value  as  indicating 
the  amount  of  readily  damageable  material  of  a  building  in 
proportion  to  its  total  value. 

Each  column  of  figures  in  the  table  represents  the  data  for 
an  individual  building,  except  the  figures  for  New  York,  in  the 
second,  third,  and  fifth  columns,  which  show  the  average  for  a 
large  number  of  buildings."  * 

This  table  includes  only  buildings  closely  approximating  in  all 
particulars  the  standard  specifications  of  the  National  Board 
of  Fire  Underwriters  and,  as  it  was  demonstrated  in  the  Balti- 
more fire,  as  will  be  shown  in  the  following  paragraph,  that 
very  heavy  conflagration  damage  may  be  expected  in  such 
buildings  on  practically  all  items  of  construction  save  founda- 
tions and  steel  frame,  it  is  significant  to  note  that  these  two 
items  represent,  approximately,  only  25  per  cent,  of  the  entire 
sound  value  of  a  building.  Thus  in  the  table  on  pages  196 
to  199,  the  average  cost  of  all  of  the  foundations  scheduled 
is' 8  per  cent.,  while  the  average  cost  of  the  steel  frame  is  17.88 
per  cent.  • 

*  Compiled  by  Mr.  F.  J.  T.  Stewart,  Continental  Insurance  Company, 
New  York. 


196 


FIRE    PREVENTION    AND    FIRE    PROTECTION 


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202         FIRE    PREVENTION    AND    FIRE    PROTECTION 

Ratio  of  Fire  Damage  to  Sound  Value.  —  On  pages  200 
and  201  will  be  found  a  most  valuable  and  interesting  table, 
compiled  by  the  Baltimore  Committee  of  the  National  Board 
of  Fire  Underwriters,  showing  the  proportion  of  value  and  fire 
damage  in  the  eight  so-called  fireproof  buildings  previously 
described.  The  first  column  of  figures  for  each  building,  or  the 
A  per  cent.,  gives  the  percentages  of  cost  of  the  classified  items 
of  construction,  while  the  second  column  for  each  building,  or 
the  B  per  cent.,  gives  the  proportion  of  fire  damage  to  sound 
value  for  such  items.  The  averages  for  the  eight  buildings  are 
given  in  the  last  two  columns. 

Foundations.  —  As  would  naturally  be  expected,  the  fire 
damage  to  foundations  was  chiefly  superficial,  in  no  case  equaling 
as  much  as  5  per  cent,  of  the  sound  value. 

Steel  Frames.  —  The  average  fire  damage  to  the  steel  frames, 
13  per  cent.,  is  not  a  true  index  of  conditions  ordinarily  to  be 
expected,  for  the  reason  that  excessive  damage  to  steel  work 
occurred  in  the  Herald  and  Equitable  Buildings  for  reasons 
previously  described.  If  these  two  buildings  are  omitted  from 
consideration,  the  average  fire  damage  to  the  steel  frames  of 
the  other  six  buildings  is  found  to  be  but  5  per  cent. 

Mason  Work.  —  The  table  shows  a  wide  range  of  fire  damage 
in  the  various  items  classified  under  this  heading,  but  several 
points  are  noticeable,  viz.,  the  uniformly  high  damage  resulting 
to  stone  work,  ornamental  terra-cotta,  cinder  concrete  filling 
and  partitions.  The  average  damage  to  brickwork  was  greatly 
increased  through  extensive  reconstruction  made  necessary  by 
the  failure  of  other  materials. 

Equipment  and  Interior  Finish,  as  might  be  anticipated,  show 
heavy  losses,  ranging  from  45  per  cent,  to  98  per  cent. 

Causes  and  Remedies.  —  It  has  been  pointed  out  that, 
obviously,  the  most  valuable  tests  of  fire-resisting  methods  are 
to  be  found  in  those  actual  fires  which  have  occurred  in  buildings 
intended  by  their  construction  to  resist  fire.  Such  tests  are 
always  unexpected,  and  hence  represent  practical  conditions  of 
everyday  occurrence;  at  the  same  time  both  good  and  bad 
features  of  construction,  mistakes,  omissions  or  weaknesses  are 
made  manifest,  as  well  as  those  enduring  qualities  which  justify 
the  faith  reposed  in  them.  Although  scientific  research  and 
investigation  and  comparative  data  as  to  the  fire-resistance  of 
various  materials  are  exceedingly  valuable,  and  hence  greatly 


FIRES    IN    FIRE-RESISTING    BUILDINGS  203 

to  be  desired,  still,  such  specific  tests  as  are  described  in  following 
chapters  are  not  to  be  compared  for  practical  utility  to  those 
actual  tests  afforded  by  the  burning  of  fire-resisting  structures; 
and  it  is  for  this  reason  that  the  many  fires  described  in  this 
chapter  have  been  examined  in  sufficient  detail  to  bring  out  the 
more  interesting  or  the  more  instructive  lessons  for  guidance  in 
present  or  future  practice.  Many  other  fires  besides  those  here 
described  have  occurred  in  fire-resisting  buildings,  and  some  of 
great  value  for  purposes  of  study  in  even  non-fire-resisting  build- 
ings, but  the  above-mentioned  fires  constitute  most  of  the  better 
known  and  certainly  the  most  frequently  quoted  instances,  so 
that  the  aggregate  of  the  experiences  afforded  by  these  examples 
may  be  taken  as  a  fair  and  safe  standard  from  which  to  derive 
certain  deductions  as  to  the  causes  of  fire  damage  and  the 
remedies  therefor. 

Considering,  then,  all  of  the  fires  described,  in  connection  with 
the  Baltimore  and  San  Francisco  conflagrations,  it  must  be 
admitted  that  buildings  can  be  rendered  fire-resisting  in  all  their 
essential  structural  parts,  against  even  the  severest  tests  afforded 
by  unusual  conflagration  conditions.  It  may  be  questioned 
whether  any  single  structure  has  actually  demonstrated  this. 
Possibly  not,  to  a  full  extent;  but,  considering  the  very  com- 
mendable showing  made  by  several  of  the  buildings  in  the  Balti- 
more fire,  if  we  should  add  to  their  good  points  certain  other 
features  which  have  amply  demonstrated  their  worth  in  the 
same  or  other  fires,  the  resulting  structure,  were  the  practice 
oftener  tried,  would  certainly  far  surpass  in  fire  resistance  even 
the  best  which  has  so  far  been  done. 

Conflagrations.  —  The  usual  causes  of  conflagrations  have 
been  enumerated  in  Chapter  I  (see  page  7) .  These  causes  may 
be  divided  into  two  general  heads,  —  municipal  weaknesses, 
such  as  lax  laws  as  to  uniformity  of  fire-resisting  construction, 
low-water  pressure  or  inefficiency  in  fire  departments,  etc.  — 
and  weakness  in  the  design,  construction  or  equipment  of  indi- 
vidual buildings.  Any  serious  attempt  at  remedying  the  fire 
problem  must,  therefore,  consider  these  causes. 

If  we  fully  appreciated  the  lessons  of  the  past,  conflagrations 
would  become  impossible.  Paterson,  Baltimore,  San  Francisco, 
and  Chelsea  all  demonstrated  the  crying  necessity  for  uniformity 
in  our  laws  relating  to  fire-resisting  construction. 

If  uniform  requirements  cannot  be  attained,   Paterson  has 


204         FIRE    PREVENTION    AND    FIRE    PROTECTION 

shown  how  most  effective  results  can  be  secured  through  the 
use  of  blank  walls  abutting  dangerous  risks,  while  Rochester 
demonstrated  the  folly  of  allowing  unprotected  openings  be- 
tween a  fire-resisting  structure  and  a  hazardous  neighbor. 

Fire-resisting  buildings  have  not  formed  perfect  fire  stops  in 
conflagrations,  but  they  have  greatly  prevented  the  further 
spread  of  conflagration  conditions  in  several  instances,  notably 
as  illustrated  by  the  Paterson  Savings  Institution  and  the  Pater- 
son  City  Hall,  and  by  those  buildings  in  the  Baltimore  fire 
which  served  to  protect  in  great  measure  the  City  Hall  and 
Postoffice.  All  of  these  buildings  formed  valuable  aids,  while 
being  seriously  damaged  in  themselves,  owing  principally  to 
the  lack  of  consideration  for  the  external  hazard. 

External  Hazard.  —  The  external  hazard  furnished  by  dan- 
gerous neighbors  and  the  necessity  for  adequate  protection 
against  such  hazard  were  plainly  shown  in  the  cases  of  the 
Vanderbiit  and  the  Home  Insurance  Buildings,  and  particularly 
emphasized  in  the  Baltimore  and  San  Francisco  conflagrations. 
If  blank  walls  are  impracticable,  remedy  may  be  found  in  pro- 
viding fire-resisting  windows,  as  described  in  Chapter  XIV. 

Planning.  —  Certain  fundamental  facts  regarding  fire-resisting 
planning  are  also  emphasized  through  these  fire  lessons.  The 
Home  Store  Building  and  the  Parker  Building  fires  both  showed 
how  rapidly  and  effectively  fire  may  be  communicated  by  means 
of  light  shafts,  dumb  waiters  or  other  vertical  openings.  The 
Metropolitan  Opera  House  fire  developed  many  serious  defects 
in  planning,  while  the  Iroquois  Theater  and  the  Asch  Building 
fires  both  revealed  glaring  defects  in  the  matter  of  proper  exits. 
The  Vanderbiit  Building  fire  illustrated  how  crooked  and  poorly 
designed  stairways  may  hamper  the  effective  working  of  the 
fire  department. 

Faulty  Construction.  —  False  economy  or  careless  fireproofing 
will  be  found  responsible  for  many  seeming  failures  of  fire-re-  < 
sisting  construction.  Witness  the  totally  inadequate  floor  con- 
struction of  the  Equitable  Building,  Baltimore,  and  in  the 
Parker  Building;  the  unprotected  roof  construction  in  the  Home 
Store  Building,  with  its  disastrous  results  in  two  fires;  and  the 
lack  of  column  protection  in  the  Roosevelt  Building. 

An  even  later  example  of  the  folly  of  spanning  an  otherwise 
fire-resisting  building  by  means  of  unprotected  steel  trusses  is 
exhibited  in  the  fire  which  occurred  January  10,  1911,  in  the 


FIRES   IN   FIRE-RESISTING   BUILDINGS  205 

Cincinnati  Chamber  of  Commerce  Building,  where  the  failure 
of  such  trusses  under  fire  caused  a  collapse  which  involved 
nearly  a  total  loss  to  the  building.*  The  lack  of  protection  to 
these  trusses  was  in  violation  of  the  present  building  ordinance, 
but  the  building  was  erected  in  1888-9,  and  the  building  code 
is  not  retroactive  in  regard  to  its  requirements  for  fire  protection. 

Examples  of  the  improper  use  of  materials  are  afforded  by 
the  Chicago  Athletic  Club  Building  fire,  where  wood  nailing 
strips  were  used  around  important  load-bearing  columns;  by 
the  Home  Office  Building,  where  terra-cotta  partitions  were 
built  upon  the  wood  floors  or  upon  wood  nailing  strips;  and 
by  numerous  other  instances,  especially  in  the  Baltimore  build- 
ings, where  either  proper  materials  have  been  used  in  improper 
manner,  or  where  improper  materials  have  been  relied  upon  for 
fire  resistance. 

Faulty  details  which  have  been  so  glaringly  shown  up  in 
actual  tests  by  fire  are  too  numerous  to  even  summarize,  as 
innumerable  partial  or  total  failures  have  occurred  in  floors, 
column  protections,  partitions,  walls,  etc. 

The  Minimizing  of  Fire  Losses;  Reconstruction. — A 

study  of  the  items  entering  into  fire  damage  discloses  the  fact  that 
a  very  large  proportion  of  it  is  due  to  the  loss  of  the  architectural 
finish,  such  as  face  brickwork,  ornamental  terra-cotta  and  stone- 
work on  the  exterior;  marble  dadoes,  columns  and  other  finish 
on  the  interior;  wooden  door -and  window' frames,  wooden  doors 
and  windows,  ornamental  grillwork,  etc.  If  the  fireproof  build- 
ing problem  is  to  be  solved  in  such  a  manner  that  conflagrations 
will  not  cause  serious  losses,  it  would  seem  that  radical  revision 
of  the  method  of  finish  is  necessary.  As  the  finish  must  prac- 
tically be  a  total  loss  anyway,  it  should  be  so  devised  that  it  can 
be  replaced  at  small  expense.  This  requirement,  however,  makes 
it  impossible  to  adopt  a  material  for  the  construction  which,  as 
the  architects  say,  finishes  itself  —  because,  if  the  exposed  surface 
is  destroyed,  the  material  becomes  a  total  loss.  It  would  seem 
that  for  the  exterior  of  the  structure,  walls  well  built  of  good, 
common  brick,  laid  in  Portland-cement  mortar,  or  else  of  rein- 
forced concrete,  could  be  finished  on  the  outside  with  stucco, 
pebble  dash  or  some  similar  material.  The  opportunity  for 
the  effective  use  of  colors  here  would  be  very  great.  If  the  build- 
ings were  exposed  to  a  fire,  the  exterior  finish  would  probably 
be  a  total  loss,  but  its  value  in  dollars  and  cents  is  small.  The 
fire  might  even  strip  it  off  and  cause  serious  spalling  to  the  main 
wall  underneath,  but,  even  so,  the  operation  of  renewing  the 
finish  would  furnish  adequate  repairs  for  the  main  wall  itself. 

*  See  Engineering  News,  February  2,  1911,  for  a  more  complete  account. 


206         FIRE   PREVENTION   AND   FIRE   PROTECTION 

On  the  other  hand,  if  face  brick  or  stone  or  ornamental  terra- 
cotta be  spalled,  the  loss  is  total;  the  original  finish  cannot  be 
renewed,  except  by  tearing  the  wall  down  and  rebuilding  it.  On 
the  interior,  combustible  trim  of  all  kinds  should  be  eliminated 
and  marble  or  stone  finish  should  be  securely  protected  from  the 
access  of  fire.  Enameled  bricks  and  enameled  tiles  should  also 
be  made  secure  against  not  only  the  direct  access  of  fire  but 
against  the  effects  of  high  temperatures  however  applied.  In- 
stead of  marble  wall  finish  or  enameled  bricks  or  tiles,  wall 
plaster  of  a  good  quality,  finished  with  enamel  paint,  furnishes 
a  perfectly  satisfactory  substitute,  so  far  as  utility  and  sanitary 
qualities  are  concerned.  If  such  finish  is  destroyed  by  fire,  its 
renewal  is  a  matter  of  relatively  small  cost. 

All  interior  partitions  should  be  so  solidly  constructed  that 
there  would  be  no  question  whatever  of  a  fire  ever  getting  through 
them.  That  ought  to  be  absolutely  impossible.  Stairways, 
stairway  halls  and  other  places  where  elevator  grills,  ornamental 
balustrades,  etc.,  might  be  used  should  be  so  located  that  no 
fire  would  ever  get  into  them,  and  they  should  be  kept  absolutely 
free  of  combustible  matter  of  all  sorts  and  descriptions.  Wooden 
floor  finish  should  not  be  allowed  in  any  portion  of  the  building. 
All  doors,  door  frames,  window  frames  and  window  sash  should 
be  of  metal  or  of  wood  covered  with  metal.  All  important  open- 
ings should  have  doors  on  both  sides  of  the  wall,  the  idea  being 
so  to  design  the  interior  of  the  building  that  a  fire  starting  in 
any  one  room  could  be  left  to  burn  itself  out  not  only  without 
being  communicated  to  other  rooms  or  to  the  corridors,  but  also 
without  causing  any  great  money  loss  to  the  building  itself  in 
the  room  or  rooms  where  the  fire  occurs.  .  .  . 

A  fire-resisting  building  is,  in  one  sense,  exactly  analogous 
to  a  fortification  —  it  needs  a  garrison  to  make  it  thoroughly 
effective.  There  is  this  difference,  however,  that  a  fire-resisting 
building  can  be  made  so  effective  in  itself  that  a  relatively  small 
garrison  can  save  it.  In  my  judgment,  a  building  thoroughly 
well  constructed  along  the  lines  indicated  in  this  report  would 
stand  in  a  conflagration  such  as  that  which  occurred  in  San  Fran- 
cisco, preserve  its  contents,  and  suffer  a  loss  to  its  own  structure 
and  finish  not  exceeding  15  per  cent.* 

*  See  Captain  John  Stephen  Sewell  in  "The  San  Francisco  Earthquake  and 
Fire,"  United  States  Geological  Survey  Bulletin,  No.  324. 


CHAPTER  VII. 

THE    MATERIALS    OF    FIRE-RESISTING    CONSTRUC- 
TION. 

Definition  of  Fire-resisting  Materials  and  Constructions. 

—  No  material  with  which  we  are  at  present  acquainted,  at 
least  to  any  commercial  extent,  is  " fireproof"  or  capable  of 
withstanding  fire  beyond  certain  fixed  limits;  for  under  severe 
enough  conditions  all  materials  of  building  construction  fail 
sooner  or  later.  This  fact  was  plainly  proven  at  Baltimore  and 
again  at  San  Francisco.  In  the  report  of  a  special  committee 
of  the  American  Society  of  Civil  Engineers  on  the  "Fire  and 
Earthquake  Damage  to  Buildings,"  *  it  is  stated  that  "Unless 
one  has  been  an  eye  witness,  it  is  difficult  to  realize  how  all 
materials  that  men  make  into  the  shape  of  buildings  can  be  so 
utterly  destroyed  in  a  general  conflagration." 

The  word  "fireproof"  rather  describes  an  ideal  condition  yet 
to  be  attained.  Hence,  in  view  of  the  misconception  attached 
to  the  term,  through  which  many  inferior  materials  or  construc- 
tions are  made  to  appear  immune  against  fire  when,  in  fact, 
they  are  hardly  fire-resisting  to  any  material  degree,  the  word 
has  been  discarded  for  the  more  rational  term  "fire-resisting," 
which  does  not  necessarily  imply  proof  against  all  fire  damage, 
but  rather  varying  degrees  of  resistance  to  fire,  according  to  the 
material  or  construction  under  discussion.  It  was  for  these 
reasons  that  the  International  Fire  Prevention  Congress,  which 
met  in  London  in  1903,  passed  the  following  resolutions: 

1.  The  Congress,  having  given  their  careful  consideration 
to  the  common  misuse  of  the  term  "fireproof,"  now  indiscrimi- 
nately, and  often  unsuitably,  applied  to  many  building  materials 
and  systems  of  building  construction  in  use  in  Great  Britain, 
have  come  to  the  conclusion  that  the  avoidance  of  this  term  in 
general  business,  technical  and  legislative  vocabulary  is  essential. 
•  2.  The  Congress  considers  the  term  "fire-resisting"  more 
applicable  for  general  use,  and  that  it  more  correctly  describes 
the  varying  qualities  of  different  materials  and  systems  of  con- 

*  See  Trans.  Am.  Soc.  C.  E.,  Vol.  LIX,  p.  237. 

207 


208        FIRE   PREVENTION   AND   FIRE   PROTECTION 

struction  intended  to  resist  the  effect  of  fire  for  shorter  or  longer 
periods,  at  high  or  low  temperature,  as  the  case  may  be;  and 
they  advocate  the  general  adoption  of  this  term  in  place  of  the 
word  " fireproof." 

Relation  of  Materials  to  Fire-resisting  Construction.  — 

The  efficiency  of  fire-resisting  construction  depends  largely  upon 

1.  The  choice  of  materials  employed  for  the  essential  struc- 
tural portions  of  the  building; 

2.  The  materials   used  for   insulating    or    protecting    those 
load-bearing  members  which,  of  necessity,  are  not  fire-resisting; 

3.  The  limitation,  as  far  as  may  be  possible,  of  combustible 
finish  or  trim. 

Practical  considerations  involving  the  choice  or  use  of  ma- 
terials will  include  a  knowledge  as  to  their  ability  to  withstand 
severe  test  by  fire  and  water,  their  availability  and  cost,  the 
possibilities  of  reconstruction  after  fire,  their  strength,  the  mass 
or  adequacy  which  may  be  required,  the  shape  or  form  of  the 
material  which  will  give  best  results,  the  methods  of  use,  as  well 
as  the  protection  which  should  be  afforded  by  auxiliary  equip- 
ment. 

Limitations  of  Materials.  —  As  before  said,  even  the  best 
of  materials,  used  in  the  most  discriminating  manner,  are  limited 
as  to  their  endurance  and  effectiveness  by  the  severity  and 
the  duration  of  their  exposure.  Hence  a  thoroughly  fire- 
resisting  building  is  impossible  unless 

(a)  The  intensity  of  heat  and  the  time  during  which  it  is 
applied  can  be  limited,  or 

(6)  Unless  the  materials  which  are  counted  on  to  resist  fire 
are  given  an  initial  excess  of  strength,  so  as  still  to  retain  an 
acceptable  factor  of  safety  after  depreciation  by  fire. 

The  first  alternative  is  the  essence  of  fire  protection.  The 
limitation  of  heat  intensity  becomes  a  question  of  design  —  the 
isolation  of  dangerous  risks,  protection  against  exposure  hazard, 
the  limitation  of  areas  and  the  minimizing  of  combustible  trim, 
etc.  The  limitation  of  time  during  which  the  fire  can  operate 
becomes  a  question  of  detection  and  extinguishment  by  means 
of  auxiliary  equipment. 

The  second  alternative  is  not  based  on  sound  principles  of 
fire  protection,  in  that  the  destruction  of  contents  and  com- 
bustible trim  is  assumed,  and  that  in  sufficient  quantity  to 
engender  a  heat  severe  enough  to  weaken  the  construction, 


MATERIALS    OF   FIRE-RESISTING    CONSTRUCTION      209 

But  if  dangerous  contents  must  be  assumed  without  the  pro- 
tection of  auxiliary  equipment,  this  reinforcement  of  structural 
materials  may  prove  the  safeguard  of  the  structure.  Thus,  in 
the  employment  of  concrete  construction  under  conditions  of 
possible  severity,  prudent  design  would  consider  the  inevitable 
destruction  or  weakening  of  the  material  to  a  greater  or  less 
depth,  and  provide  for  such  depreciation  in  strength  in  the 
original  design. 

It  has  previously  been  shown  in  the  " Conclusions"  of  Chap- 
ter VI,  that,  notwithstanding  these  limitations,  past  experience 
certainly  justifies  the  statement  that  buildings  may  be  suc- 
cessfully and  economically  designed  so  as  to  render  them  prac- 
tically fire-resisting. 

Fire  and  Water  Tests.  —  The  behavior  of  materials  under 
tests  by  fire  and  quenching,  whether  such  tests  are  made  in 
laboratories,  testing  stations  or  in  actual  fires,  concerns  first, 
the  endurance  of  the  material  from  the  standpoint  of  damage, 
thus  involving  the  extent  of  reconstruction  or  repair  which  may 
be  necessary;  second,  the  question  of  strength  after  fire  test; 
and  third,  the  conductivity  of  heat  developed  in  those  materials 
which  are  to  be  used  for  the  protection  of  other  materials. 

The  actual  fires  described  in  Chapter  VI  furnish  numerous 
examples  of  fire  damage  resulting  in  many  materials.  Recon- 
struction or  repair  and  the  range  of  temperatures,  which  is  to  be 
expected  in  fires  of  great  intensity,  have  also  been  discussed  in 
Chapter  VI,  while  the  test  conditions  of  heat  and  water  appli- 
cations required  by  several  of  the  more  prominent  testing  stations 
have  been  given  in  Chapter  V. 

The  strength  remaining  in  materials  or  constructions  after 
severe  fire  and  water  tests  is  of  most  vital  importance.  It  has 
previously  been  pointed  out  that  early  tests  of  fire-resisting 
materials  placed  too  much  emphasis  on  the  load-bearing  qualities 
before  fire  test ;  but  as  practically  all  materials  and  constructions 
in  common  use  can  be  designed  to  carry  safely  almost  any  loads 
which  are  liable  to  occur  in  practice,  the  question  of  doubt  lies 
in  their  qualities  after  fire  test.  Hence  some  of  the  materials 
discussed  in  this  chapter  will  be  considered  principally  from  this 
standpoint,  or,  in  the  case  of  protective  coverings,  from  the 
standpoints  of  conductivity  and  efficiency. 

Strength  of  Materials.  —  The  strength  of  materials  under 
normal  conditions  is  not  pertinent  to  a  handbook  on  fire  pro- 


210         FIRE    PREVENTION    AND    FIRE    PROTECTION 

tection,  except  in  so  far  as  the  possibility  or  advisability  of 
structural  design  along  certain  lines  may  be  affected.  Thus, 
if  the  building  is  to  be  of  great  height,  a  steel  framework  be- 
comes necessary  or  advisable  —  necessary  where  the  loads  on 
very  high  brick  or  masonry  walls  exceed  the  crushing  strength 
of  the  material,  and  advisable  for  lesser  heights  where  masonry 
load-bearing  walls  become  uneconomical  on  account  of  the 
room  occupied. 

Attention  might  here  be  called  to  the  widening  possibilities 
in  the  use  of  tile  column  and  wall  constructions,  owing  to  the 
very  considerable  loads  which  may  be  carried,  as  is  pointed  out 
in  more  detail  in  Chapters  XII  and  XX. 

Cost:  Availability.  —  In  building  and  construction  work 
the  substitution  of  the  materials  of  the  second  group  (i.e.,  stone, 
clay  products,  cement,  and  concrete)  for  the  more  commonly 
used  wood  and  metal  manufactures  should  be  encouraged  as 
having  an  important  influence  on  the  preservation  of  the  supplies 
of  the  more  perishable  and  scarcer  materials.  The  use  of  build- 
ing stone  and  clay  and  cement  products  in  this  country  has  been 
restricted  by  competition  with  the  much  cheaper  wood  products 
and  the  more  easily  fabricated  and  more  available  metal  products. 
Improved  methods  of  preparing  the  raw  materials  for  use  in 
building  construction  are,  however,  rapidly  diminishing  the 
difference  in  cost,  and  careful  investigation  as  to  their  structural 
qualities  and  the  more  suitable  structural  forms  would  have  an 
important  influence  in  further  reducing  this  difference  in  cost 
and  in  enlarging  the  use  of  the  more  permanent  materials. 

Within  the  last  decade  the  value  of  the  cement  manufac- 
tures of  this  country  has  increased  from  $9,859,000  to  $55,803,000 
or  nearly  sixfold.  In  the  same  time  the  value  of  the  clay  prod- 
ucts has  increased  from  $74,487,000  to  $183,942,000,  or  has  more 
than  doubled,  and  that  of  the  building  stone  has  increased  from 
$26,635,000  to  $71,106,000  or  has  nearly  trebled.  As  the  Gov- 
ernment, through  its  investigations,  is  determining  the  strength, 
durability,  and  fire-resisting  properties  of  these  materials  and  the 
more  suitable  forms  for  their  use,  and  is  disseminating  information 
relative  to  their  comparative  cheapness  and  great  permanence, 
a  still  greater  relative  increase  in  their  use  may  be  confidently 
expected  in  the  near  future. 

Within  the  last  few  years  marvelous  strides  have  been 
made  in  the  substitution  of  iron  and  steel  for  wood  as  a  result 
of  the  careful  investigations  of  their  properties  made  by  engi- 
neers, physicists,  and  chemists,  and  the  great  amount  of  atten- 
tion paid  to  their  fabrication  by  manufacturers  and  architects. 
More  recently  the  engineering  and  technical  professions  have 
advanced  to  a  great  extent  the  uses  of  cement  in  concrete  manu- 
factures. But  in  a  much  greater  period  little  has  been  done 


MATERIALS    OF   FIRE-RESISTING    CONSTRUCTION      211 

toward  ascertaining  the  physical  and  chemical  properties  and 
the  best  modes  of  manufacture  and  use  of  clay  products  and 
stone.  Undoubtedly  great  progress  in  the  use  of  all  these  ma- 
terials may  now  be  reasonably  expected  with  proper  encourage- 
ment from  the  Government  as  an  exampler  in  its  method  of 
studying,  testing  and  using  them. 

The  investigations  in  progress  by  the  Geological  Survey 
indicate  that  smaller  quantities  of  cement-making  materials,  of 
gravel  and  sand  suitable  for  concrete  structures,  and  of  clay 
suitable  for  making  brick  will  suffice,  and  also  show  how  con- 
struction can  be  done  at  least  cost.  Already,  not  only  in  tree- 
less regions,  but  elsewhere  also,  the  use  of  such  materials  is  rapidly 


Other  Considerations  involving  the  choice  or  use  of  ma- 
terials, such  as  mass  or  adequacy,  methods  of  use  and  protection 
afforded  by  auxiliary  equipment,  etc.,  are  discussed  in  many 
later  chapters. 

MATERIALS 

Wrought  Iron  and  Steel.  —  No  material  used  in  building 
construction  is  as  unreliable  and  treacherous  as  unprotected 
wrought-iron  or  steel.  Owing  to  twisting,  warping  and  expan- 
sion under  moderate  heat,  it  is  not  uncommon  to  hear  old  and 
tried  firemen  declare  that  they  would  much  rather  take  chances 
in  fighting  fire  in  a  building  of  inflammable  construction  than 
in  a  structure  containing  unprotected  wrought-iron  or  steel 
beams,  girders,  columns  or  trusses.  Load-bearing  members  of 
steel  or  wrought-iron  must,  therefore,  be  protected  by  adequate 
fire-resisting  coverings.  Floor  beams  and  girders  should  be 
protected  by  the  terra-cotta  or  concrete-floor  system,  columns  by 
the  exterior  masonry  walls  or  by  envelopes  of  brick,  terra-cotta 
or  concrete,  while  trusses  or  other  constructions  of  iron  or  steel 
require  adequate  protection  against  heat.  Examples  of  serious 
failures  from  disregarding  these  precautions  are  too  numerous 
to  mention. 

Expansion  of  Steel.  —  Unprotected  steel  will,  under  the  action 
of  high  temperatures,  so  expand  as  to  cause  the  deformation, 
if  not  complete  ruin,  of  the  structure.  For  each  degree  Fahren- 
heit of  elevation  of  temperature,  soft  steel  or  iron  will  extend 
about  TSTnnFTT  part  of  its  length.  For  each  100°  F.  increase  in 

*  From  United  States  Geological  Survey  Bulletin  No.  418,  "The  Fire  Tax 
and  Waste  of  Structural  Materials  in  the  United  States,"  1910. 


212         FIRE    PREVENTION   AND    FIRE    PROTECTION 

temperature  the  increase  in  length  would  be  about  one  inch  in 
125  feet.  Where  unprotected  iron  or  steel  beams,  girders  or 
trusses  are  supported  by  masonry  walls,  this  expansion  is  often 
sufficient  to  cause  the  overthrow  of  the  bearing  walls. 

Fire  Tests  on  Steel  Columns.  —  The  earliest  experimental 
fire  and  water  tests  on  cast-iron  and  steel  columns  under  load 
were  made  in  Hamburg  in  1886.  These  tests*  plainly  demon- 
strated the  utter  unreliability  of  unprotected  steel. 

Very  few  American  fire  tests  have  been  made  on  iron  or  steel 
columns.  One  series  of  such  tests,  however,  was  noteworthy, 
—  viz.,  those  nxade  in  1896  by  a  committee  representing  the 
Tariff  Association  of  New  York,  the  Architectural  League  of 
New  York  and  the  American  Society  of  Mechanical  Engineers.! 
The  tests  were  few  in  number,  but  most  important  in  results. 

Five  full-sized  columns  (two  of  steel  and  three  of  cast-iron) 
were  tested  in  brick  furnaces  which  were  built  for  the  purpose. 
The  columns  were  made  of  forms  and  lengths  as  representing 
common  practice,  and  they  were  placed  in  compression  by  means 
of  a  hydraulic  ram  to  obtain  loadings  approximating  those  found 
under  ordinary  conditions. 

Test  No.  1.  The  column  tested  was  unprotected,  box- 
shaped,  made  of  two  steel  channels  and  side  plates.  The  highest 
temperature  recorded  was  1230°  F.  After  an  exposure  of  1  hour 
and  21  minutes  the  column  began  to  yield  under  a  load  of  46.00 
tons,  the  temperature  being  1210°  F.  The  column  buckled  at 
the  center  by  the  wrinkling  of  the  plates.  The  breaking  load 
was  computed  by  Gordon's  formula  to  be  342  tons. 

Test  No.  2  consisted  of  an  unprotected  8-inch  standard 
steel  Z  column.  The  maximum  temperature  recorded  was 
1375°  F.  A  uniform  loading  of  84.8  tons  was  maintained  during 
the  entire  test.  The  column  commenced  to  yield  after  an  ex- 
posure of  24  minutes,  the  temperature  being  1125  degrees. 
Deflection  occurred  at  the  lower  third  point.  The  computed 
breaking  load  was  303  tons. 

From  these  tests  it  may  be  stated  that  unprotected  steel 
columns  will  commence  to  yield  at  temperatures  of  from  1000° 
to  1200°  F. 

Experiences  in  Baltimore  and  San  Francisco  Fires.  —  The 
possibility  of  successfully  protecting  the  steel  frameworks  of 
buildings  against  even  such  severe  conflagration  conditions  as 

*  See  "The  Behavior  of    Iron  Columns  at  High  Temperatures,"   by  A. 
Gottlieb,  Journal  Assoc.  of  Engineering  Societies,  February,  1892. 
t  See  Engineering  News,  August  6,  1896. 


MATERIALS   OF   FIRE-RESISTING   CONSTRUCTION      213 

obtained  in  both  the  Baltimore  and  San  Francisco  fires  was 
conclusively  demonstrated  in  those  experiences.  Thus  the  in* 
surance  adjuster's  report  on  the  twelve-story  Calvert  Building 
shows  a  loss  on  the  steel  frame  of  only  1.37  per  cent,  of  its  sound 
value,  and  on  the  eleven-story  Union  Trust  Company's  Building 
of  1.03  per  cent.,  neither  of  these  structures  having  been  fire- 
proofed  in  any  too  commendable  a  manner.  Inadequate  pro- 
tection of  the  metal  frame  in  the  Equitable  Building  resulted 
in  a  loss  of  43  per  cent,  of  the  sound  value,  a  good  example  of 
poor  economy. 

In  spite  of  very  many  poorly  protected  steel  columns  in  the 
Baltimore  fire-resisting  buildings,  only  two  were  subjected  to 
serious  injury. 

As  regards  the  San  Francisco  fire,  "it  can  be  truthfully  stated 
that  perfect  fireproofing  of  buildings,  even  in  those  of  the  newest 
and  most  modern  type,  was  the  exception  and  not  the  rule. 
The  bent  or  broken  columns  and  the  distorted  or  disfigured  steel 
girders  in  many  of  the  burned  buildings  demonstrate  this  fact. 
Wherever  structural-steel  framework  was  covered  with  fire- 
proofing  material  of  the  best  design,  executed  with  conscientious, 
skillful  workmanship,  the  steel  remained  uninjured  after  the 
fire."* 

Effect  of  Fire  on  Uncompleted  Steel  Frames.  —  A  very  unusual 
test  by  fire  of  uncompleted  steel  frames  was  afforded  by  the 
San  Francisco  conflagration. 

Four  of  these  steel  frames  were  completed  and  one  was  up 
two  stories.  In  four  of  the  cases  the  floor  arches  were  not  yet 
in.  All  the  frames  appeared  to  be  uninjured,  except  that  an 
occasional  beam  near  the  street  grade  has  sagged  and  will  have 
to  be  replaced.  All  were  in  the  path  of  the  maximum  confla- 
gration sweep;  but  they  appear  to  have  been  affected  only  by 
the  wooden  material,  scaffolding,  etc.,  on  their  own  premises, 
i.e.,  where  close  to  such  material  there  was  a  local  effect;  but 
the  frames  seem  to  have  been  indifferent  to  the  exposure  at  any 
considerable  distance.  It  is  probably  the  case  that,  in  the 
long-range  blast,  the  temperatures,  though  above  the  point  of 
wood  ignition,  are  below  the  softening  temperature  of  iron  and 
steel,  except  at  very  close  quarters;  so  that  the  general  effects 
are  confined  to  expansion;  and  conflagration  experience  has 
pretty  well  settled  the  fact  that  a  steel  frame  can  undergo  a 
large  and  uneven  range  of  expansion  and  subsequent  contraction 
without  serious  injury  to  its  own  members  or  their  connections, 


*  Professor  Frank  Soul6,  in  Bulletin  No.  324. 


214         FIRE    PREVENTION    AND    FIRE    PROTECTION 

provided  the  temperature  is  short  of  the  softening  point.     These 
frames  also  had  the  advantage  of  being  largely  free  from  load.* 

Cast-Iron.  —  As  employed  in  building  construction,  the  use 
of  cast-iron  is  generally  limited  to  columns  or  mullions  for  the 
carrying  of  greater  or  less  loads,  and  to  light  exterior  or  interior 
constructions  of  an  ornamental  nature,  generally  carrying  minor 
loads  only,  such  as  pilasters,  cornices,  portions  of  stairs,  etc. 
Owing  to  the  difficulty  of  obtaining  homogeneous  castings,  of 
uniform  texture  and  thickness,  cast-iron  is  recognized  as  the 
most  unreliable  material  used  for  constructive  purposes.  When 
subjected  to  fire  and  water  tests,  this  uncertainty  as  to  its  be- 
havior is  greatly  increased. 

Behavior  in  Moderate  Fires.  —  As  the  result  of  tests  (see  later 
paragraph)  and  actual  experiences  in  fires,  it  may  be  stated  that 
unprotected  cast-iron  columns  may  stand  practically  unharmed 
up  to  temperatures  of  1300  or  1500°  F.,  while  carrying  heavy 
loads,  and  even  with  frequent  applications  of  cold  water  while 
the  metal  is  at  a  red  heat.  After  many  moderate  fires,  unpro- 
tected cast-iron  columns  have  been  found  to  be  in  a  sufficiently 
good  condition  to  warrant  their  reuse.  Thus  in  the  Ames 
Building  fire  in  Boston  in  1889,  while  a  number  of  cast-iron 
columns  were  apparently  broken  by  their  own  fall,  or  that  of 
debris  upon  them,  yet  comparatively  few  showed  evidence  of 
failure  from  heat.  Experiences  in  English f  and  American 
cotton  mills  also  show  that  the  fire  resistance  of  such  columns 
is  undoubtedly  greatly  superior  to  steel. 

Failures  of  Cast  Columns.  —  It  has  been  shown  in  Chapter  VI 
that  temperatures  exceeding  2000°  F.  are  reached  in  confla- 
grations or  even  in  fires  in  individual  buildings.  Hence  the 
limit  of  endurance  of  even  cast-iron  columns  is  very  apt  to  be 
exceeded,  and  failures  should  be  expected. 

In  the  Baltimore  conflagration,  cast-iron  columns  and  store 
fronts,  etc.,  went  down  on  every  hand,  and  while  most  cases  of 
failure  were  undoubtedly  due  to  falling  w^lls,  etc.,  cases  of  column 
failure  by  buckling  occurred  in  the  Chamber  of  Commerce  and 
Equitable  Buildings,  and  by  collapse  in  the  National  Mechanics' 
Bank  Building. 

*  From  report  of  Mr.  S.  A.  Reed  to  National  Board  of  Fire  Underwriters. 

t  For  examples,  see  "Comparison  of  English  and  American  Types  of  Fac- 
tory Construction,"  by  John  R.  Freeman,  in  Journal  of  Assoc.  of  Engineering 
Societies,  January,  1891. 


MATERIALS   OF   FIRE-RESISTING    CONSTRUCTION      215 

A  number  of  cases  of  the  collapse  of  structures  due  to  unpro- 
tected cast-iron  columns  occurred  in  the  San  Francisco  fire,  and 
there  were  numerous  examples  of  another  inherent  weakness  in 
cast  columns,  viz.,  the  presence  of  internal  stresses  in  the  metal, 
caused  by  the  cooling  and  shrinking  of  the  metal  when  cast. 
Such  internal  stresses  are  particularly  liable  to  occur  at  the  tops 
of  columns  where  lugs  or  brackets  are  cast  on  the  shaft  (as  is 
usually  the  case),  thus  resulting  in  weaknesses  at  such  points. 
Many  instances  were  found  where  evidently  such  weaknesses, 
under  the  additional  stress  of  heating  and  cooling,  caused  the 
heads  of  cast  columns  to  break  off,  but  still  remain  attached 
to  the  girders  and  beams  by  means  of  the  lugs  and  bolts. 

Another  objection  to  the  use  of  cast  columns  is  the  fact  that 
failure,  from  whatever  cause,  usually  means  the  collapse  of 
the  structure.  In  the  San  Francisco  fire  literally  hundreds  of 
instances  were  found  of  the  partial  settling  or  deflection  of  steel 
columns,  but  the  collapse  of  the  floors  around  same  occurred  in 
only  one  or  two  instances.  In  the  Parker  Building  fire,  pre- 
viously described  in  Chapter  VI,  the  failure  of  cast  columns 
resulted  in  a  collapse  so  sudden  that  three  firemen  were 
killed  and  many  injured.  Injury  to  large  portions  of  the 
building  and  great  loss  of  contents  in  the  lower  stories  also 
resulted. 

Fire  Tests  of  Cast  Columns.  —  The  tests,  conducted  in  New 
York  City  in  1896,  previously  referred  to,  included  three  tests 
on  cast  columns,  as  follows: 

Test  No.  3  was  of  a  cast-iron,  round,  hollow  column,  with 
faced  flanges  at  both  ends.  The  highest  temperature  registered 
was  1250°  F.  Deflection  at  the  center  occurred  in  1  hour  and 
8  minutes  after  start  of  test.  The  load  was  84.8  tons,  tem- 
perature 1137  degrees.  The  computed  breaking  load  was  451 
tons,  safe  load  90.2  tons. 

Test  No.  4  consisted  of  an  unprotected  cast-iron,  round, 
hollow  column.  Bending,  at  about  the  center  of  the  column, 
started  after  35  minutes  of  exposure,  under  a  loading  of  84.8  tons 
and  a  temperature- of  1350  degrees.  Eight  minutes  later,  under 
the  same  loading  and  a  temperature  of  1550  degrees,  fracture 
occurred  at  the  center  of  the  column  where  the  deflection  was 
greatest.  A  crack  was  also  developed  above  the  point  of  fracture 
on  the  convex  side. 

Test  No.  5  combined  a  fire  and  water  test  on  a  cast-iron 
column,  8  inches  diameter  by  1-inch  metal.  The  maximum  tem- 
perature recorded  was  1300°  F.  The  column  started  bending 
in  2  hours  and  15  minutes  after  the  beginning  of  the  test,  after 


216        FIRE   PREVENTION   AND   FIRE   PROTECTION 

several  applications  of  cold  water.  The  temperature  was 
1275  degrees,  load  on  column  84.8  tons.  At  the  conclusion  of 
the  test  the  column  was  found  to  be  badly  bent,  but  was  other- 
wise uninjured,  although  the  column  was  at  a  red  heat  when 
water  was  last  applied. 

Conclusions.  —  The  results  of  the  above  tests  should  not  serve 
to  detract  from  the  importance  of  adequately  protecting  all 
load-bearing  members  of  cast-  or  wrought-iron  or  steel.  No 
building  can  be  deemed  fire-resisting  in  which  such  unprotected 
members  occur.  The  amount  of  protection  required  varies  in 
proportion  to  the  exposure  to  be  expected  and  to  the  load  to 
be  borne. 

Stones.  —  All  stones  under  the  action  of  severe  heat  will 
crack,  shell  or  calcine,  according  to  the  nature  of  the  material. 
Hence  the  use  of  stone  in  buildings  intended  to  be  fire-resisting 
should  be  carefully  limited  to  cases  where  severe  exposure, 
whether  from  the  burning  of  adjoining  or  nearby  property  or 
from  highly  combustible  contents,  is  not  to  be  expected.  Even 
then,  conflagration  will  almost  invariably  require  the  replace- 
ment of  stone  masonry. 

r  The  common  building  stones  comprise  granite,  limestone, 
marble  and  sandstone.  These  will  each  be  considered  in  some 
detail,  but  for  a  more  complete  illustrated  account  of  experi- 
mental fire  tests  on  various  stones,  both  early  and  recent,  the 
reader  is  referred  to  Bulletin  No.  100,  "Fire  tests  on  some  New 
York  Building  Stones,"  issued  in  1906  by  the  New  York  State 
Education  Department  (Albany,  N.Y.),  from  which  the  follow- 
ing quotations  are  taken. 

The  experimental  tests  lately  made  by  the  United  States 
Government  at  the  Underwriters'  Laboratories  in  Chicago  in- 
cluded fire-tests  on  the  four  kinds  of  stone  mentioned  above,  in 
regard  to  which  Bulletin  No.  370  states  that  "the  serious  damage 
to  the  various  natural  building  stones  precludes  any  comparison 
among  them." 

Granite.  —  Granite  will  explode  and  fly  off  in  fragments,  or 
it  will  disintegrate  into  a  fine  sand.  In  some  building  laws  the 
non-fire-resisting  character  of  granite  is  clearly  recognized,  in 
that  brick  or  terra-cotta  protection  is  required  for  granite  sup- 
porting members.  The  face  of  granite  stones  will  spall  or  split 
off  and  this  often  with  considerable  explosive  violence.  Granite 
mullions  which  have  been  exposed  to  flame  may  commonly  be 


218         FIRE    PREVENTION   AND    FIRE    PROTECTION 

seen  in  which  the  exterior  corners  have  so  split  off  as  to  leave 
the  face  V-shaped. 

The  coarse-grained  granites  were  damaged  the  most  by 
cracking  very  irregularly  around  the  individual  mineral  con- 
stituents. Naturally,  such  cracking  of  the  stone  in  a  building 
might  cause  the  walls  to  crumble.  The  cracking  is  due,  possibly, 
to  the  coarseness  of  texture  and  the  differences  in  coefficiency  of 
expansion  of  the  various  mineral  constituents.  Some  minerals 
expand  more  than  others  and  the  strains  occasioned  thereby  will 
tend  to  rupture  the  stone  more  than  if  the  mineral  composition 
is  simpler.  This  rupturing  will  be  greater,  too,  if  the  rock  be 
coarser  in  texture.  .  .  .  The  fine-grained  samples  showed  a 
tendency  to  spall  off  at  the  corners. 

The  Baltimore  fire  exhibited  many  noteworthy  examples  of 
serious  damage  to  granite.  Fig.  43  illustrates  the  interior  of 
United  States  Public  Store  House,  No.  1,  showing  one  granite 
column  entirely  gone,  and  others  badly  spalled. 

Limestone  and  Marble.  —  Limestones  and  marbles  are 
damaged  by  heat  more  than  any  other  building  stones.  They 
become  calcined  or  decomposed  into  lime  under  intense  heat. 
This  has  been  clearly  demonstrated  in  many  fires.  Limestone 
fronts  have  been  totally  destroyed,  while  the  brick  backing  has 
often  remained  comparatively  uninjured.  The  destruction  ot 
the  marble  facade  of  the  Home  Life  Building,  described  in  Chap- 
ter VI,  was  a  case  in  point.  No  incombustible  material  suffered 
more  uniform  destruction  in  the  Baltimore  fire  than  did  marble. 

The  limestones,  up  to  the  point  where  calcination  begins 
(600  to  800°  C.)  were  little  injured,  but  above  that  point  they 
failed  badly,  owing  to  the  crumbling  caused  by  the  flaking  of  the 
quicklime.  The  purer  the  stone,  the  more  it  will  crumble. 
Marble  behaves  similarly  to  limestone;  but,  because  of  the 
coarseness  of  the  texture,  also  cracks  considerably. 

Sandstone.  —  Compact,  fine-grained  sandstones  should  with- 
stand the  action  of  fire  better  than  any  other  stone  usually 
employed,  but  its  action  is  decidedly  problematical.  Thus,  in 
some  cases,  where  exposed  to  even  severe  heat,  sandstones  have 
been  comparatively  uninjured  except  for  minor  spalling,  and 
discoloration  due  to  smoke.  In  the  New  England  Building 
fire  in  Boston,  1910,  the  dark  red  sandstone  trim  stood  up  very 
well,  and  in  the  Baltimore  fire  two  buildings  of  interior  wooden 
construction  were  completely  burned  out,  as  well  as  all  the  sur- 
rounding buildings,  but  the  face  walls  of  sandstone  withstood 
the  heat  without  apparent  damage.  On  the  other  hand  in  the 


MATERIALS    OF    FIRE-RESISTING    CONSTRUCTION      219 

Bedford  street  fire  in  Boston.  1889,  in  which  the  brown  sand- 
stone buildings  designed  by  H.  H.  Richardson  were  destroyed, 
the  sandstone  was  badly  affected  by  fire  and  water. 

All  the  sandstones  which  were  tested  were  fine  grained  and 
rather  compact.  All  suffered  some  injury,  though,  in  most  cases 
the  cracking  was  along  the  lamination  planes.  In  some  cubes, 
however,  transverse  cracks  were  also  developed. 

The  variety  of  samples  was  not  great  enough  to  warrant 
any  conclusive  evidence  toward  a  determination  of  the  control- 
ling factors.  It  would  seem,  however,  that  the  more  compact 
and  hard  the  stone  is,  the  better  will  it  resist  extreme  heat.  The 
relation  of  the  percentage  of  absorption  to  the  effect  of  the  heat 
is  interesting.  In  a  general  way  the  greater  the  absorption,  the 
greater  the  effect  of  the  heat.  A  very  porous  sandstone  will  be 
reduced  to  sand  and  a  stone  in  which  the  cement  is  largely 
limonite  or  clay  will  suffer  more  than  one  held  together  by  silica 
or  lime  carbonate. 

Brickwork.  —  Many  fires  have  fully  demonstrated  the  fire- 
resisting  qualities  of  good  brickwork.  Its  ability  to  withstand 
fire  and  water  tests  depends  upon  (a)  the  method  of  manufacture, 
(6)  the  chemical  properties  of  the  materials  employed,  (c)  the 
method  of  use. 

Method  of  Manufacture.  —  When  the  old  style  up-draught 
kiln  was  used  for,  the  burning  of  the  brick,  the  position  of  the 
brick  in  the  kiln  affected  the  fire-resisting  properties.  The  clinker 
or  arch  bricks,  which  formed  the  arches  in  which  the  fire  was 
built,  were  usually  overburned  or  partially  vitrified.  These 
possessed  admirable  fire-resisting  properties,  but  for  use  in 
load-bearing  walls  or  piers  were  too  weak  and  too  brittle, 
although  very  hard.  The  soft  bricks,  which  formed  the  ex- 
terior of  the  kiln,  were  usually  underburned  and  too  soft  for 
ordinary  use.  The  body  or  hard  bricks,  in  the  interior  of  the 
mass,  could  alone  be  used  for  the  best  results  under  load  and 
fire  resistance. 

With  the  newer  styles  of  permanent  down-draught  kilns,  the 
position  of  the  briek  during  the  burning  is  much  less  important 
than  was  formerly  the  case,  as  the  quality  is  very  nearly  uniform 
throughout  the  kiln.  The  chemical  composition  of  the  clay  is 
now  the  most  important  factor  in  determining  the  fire  resistance 
of  the  brick. 

Chemical  Properties.  —  The  fire-resisting  properties  depend 
chiefly  upon  the  amounts  and  properties  of  silica  and  alumina 
in  the  clay,  and  also  upon  the  amounts  of  oxide  of  iron,  lime, 


220         FIRE   PREVENTION    AND    FIRE    PROTECTION 

magnesia,  potash,  etc.  Common  clay,  used  in  the  manufacture 
of  common  brick,  consists  principally  of  silicate  of  alumina,  lime, 
magnesia  and  oxide  of  iron.  The  latter  ingredient  adds  to  the 
hardness  and  strength  of  the  brick. 

"Uncombined  silica,  if  not  in  excess,  is  beneficial,  as  it  pre- 
serves the  form  of  the  brick  at  high  temperatures.  In  excess 
it  destroys  the  cohesion,  and  renders  the  bricks  brittle  and  weak. 
Twenty-five  per  cent,  of  silica  is  a  good  proportion."* 

For  fire-bricks  intended  to  resist  extreme  heat,  without  heavy 
loads,  silica  should  be  used  in  excess  of  the  proportion  stated 
above.  "The  presence  of  oxide  of  iron  is  very  injurious  and, 
as  a  rule,  the  presence  of  6  per  cent,  justifies  the  rejection  of  the 
brick.  In  specifications  it  should  generally  be  stipulated  that 
fire-brick  should  contain  less  than  6  per  cent,  of  oxide  of  iron,  and 
less  than  an  aggregate  of  3  per  cent,  of  combined  lime,  soda  and 
potash,  and  magnesia.  The  sulphide  of  iron  —  pyrites  —  is 
even  worse  in  its  effect  on  fire-brick  than  the  substances  first 
named." 

Method  of  Use.  —  Good  fire-resisting  brick  should  be  of  homo- 
geneous composition  and  texture,  regular  in  shape,  uniform  in 
size,  strong  and  infusible.  Experience  has  shown  that  the  most 
efficient  brick  masonry  requires  cement  mortar,  good  bonding 
by  means  of  headers,  the  tying  of  walls  to  floor  and  roof  members 
by  adequate  ties  or  anchors,  and  a  sufficient  thickness  or  mass 
to  resist  fire.  For  further  discussion  of  masonry  walls  see 
Chapter  XX. 

Fire  Tests  of  Brickwork.  —  Of  the  Geological  Survey  tests, 
Bulletin  No.  370  states  as  follows: 

The  brick  panels  probably  withstood  the  tests  better  than 
the  other  materials.  The  common  brick  tested  comprised  un- 
used new  Chicago  bricks  and  used  St.  Louis  brick.  Fifty  per 
cent,  of  the  new  bricks  were  split,  while  60  to  70  per  cent,  of  the 
old  bricks  were  not  damaged.  Lime  knots  seemed  to  be  re- 
sponsible for  most  of  the  damage  to  the  new  bricks,  as  they  were 
found  at  the  bottom  of  nearly  all  the  cracks.  The  bricks  at 
the  back  of  the  panels  were  entirely  unaffected.  While  the 
strength  tests  are  not  conclusive,  there  is  apparently  little  differ- 
ence in  the  strength  of  these  bricks  before  and  after  firing. 

Both  the  Baltimore  and  San  Francisco  fires  demonstrated 
that  good  quality  brickwork,  used  for  walls  or  column  casings, 
suffered  less  than  any  other  material. 

*  See  "A  Treatise  on  Masonry  Construction,"  I.  O.  Baker. 


MATERIALS   OF   FIRE-RESISTING   CONSTRUCTION      221 

Ordinary  well-burned  brick  of  good  quality  is  the  most  satis- 
factory fire-resistive  material  now  used  in  building  construction.* 

Where  the  walls  were  laid  with  hard  brick,  with  plenty  of 
headers  and  in  Portland-cement  mortar,  and  were  properly  tied 
to  the  floor  and  roof  members,  there  was  little,  if  any,  damage. f 

Sand-lime  Bricks  are  made,  as  is  indicated  by  their  name, 
of  sand  and  lime.  The  product  is  by  no  means  new,  as  the 
ancient  Romans  used  bricks  made  of  pulverized  lime  and  sand 
or  stone  dust,  which  were  exposed  to  the  air  to  harden.  Bricks 
of  this  character  are  still  to  be  found  in  perfect  condition.  A 
similar  process  was  followed  for  many  years  in  Germany  and 
Switzerland,  but  while  the  bricks  proved  durable,  the  process 
was  not  commercially  successful  on  account  of  the  expense  of 
the  large  quantity  of  lime  used,  and  on  account  of  the  long  time 
necessary  to  complete  the  hardening.  The  discovery  of  Dr. 
Michaelis  (a  Berlin  chemist) ,  in  1880,  that  considerably  less  lime 
could  successfully  be  used,  and  that  better  results  could  be 
obtained  by  subjecting  the  bricks  to  a  heavy  steam  pressure 
after  moulding,  caused  renewed  interest  in  the  industry,  especially 
in  and  about  Potsdam,  Germany,  where  there  is  little  stone  but 
great  deposits  of  sand.  After  careful  government  inspection 
these  bricks  were  finally  recognized  as  suitable  building  material. 
The  industry  is  now  extensive  throughout  Germany,  France, 
Switzerland  and  Great  Britain. 

The  first  sand-lime  brick  plant  to  be  started  in  the  United 
States  was  at  Michigan  City,  Indiana,  in  1901.  There  are  now 
not  less  than  200  factories  making  these  bricks  in  the  United 
States  and  in  Canada,  these  plants  ranging  from  a  capacity  of 
35,000  a  day  up  to  as  high  as  150,000  per  day. 

Process  of  Manufacture.  —  Sand-lime  bricks  are  very  similar 
to  Indiana  limestone  in  color  and  composition.  They  are  made 
of  pure  silica  sand,  cheaply  obtained  in  a  sand  bank,  and  high 
calcium  lime.  The  proportion  of  hydrated  lime  varies  some- 
what with  local  conditions  or  process  of  manufacture,  but,  broadly 
speaking,  it  may  be  said  that  7J  per  cent,  of  lime  is  used  to 
92J  per  cent,  of  the  silica,  with  a  very  small  amount  of  water. 
The  sand  is  carefully  graded  as  to  size,  so  as  to  make  a  compact 
brick,  and  in  the  mixing  process  care  should  be  taken  to  coat 

*  Baltimore  Fire,  National  Fire  Protection  Association  Report, 
t  San  Francisco  Fire,  Mr.  Richard  L.  Humphrey  in  United  States  Geological 
Bulletin  No.  324. 


222         FIRE    PREVENTION    AND    FIRE    PROTECTION 

each  particle  of  sand  with  lime.  This  mixture  is  then  pressed 
into  bricks,  and  piled  on  cars,  which  are  run  into  a  "  hardening 
cylinder,"  where  they  are  subjected  to  steam  pressure  at  from 
125  to  150  pounds  for  from  10  to  12  hours.  As  soon  as  the 
bricks  are  cool  enough  to  handle  they  possess  a  clear  metallic 
ring,  and  are  ready  for  use.  They  are  low  in  porosity  and  have 
a  high  tensile  and  crushing  strength  and,  as  chemical  action 
continues  when  they  come  in  contact  with  the  air,  they  become 
denser  and  stronger  with  age. 

While  the  natural  color  is  light  gray,  they  can  be  made  of 
almost  any  color  or  shade,  thus  affording  great  opportunities 
for  color  schemes.  They  are  also  particularly  adaptable  to 
interiors  of  factories,  warehouses,  etc.,  and  for  interior  courts, 
where  their  light  color  contributes  reflected  light  without  addi- 
tional cost.  The  cost  varies  considerably  according  to  locality 
and  grade,  ranging  from  five  dollars  per  thousand  for  "sand- 
lime  commons"  in  Chicago,  to  forty-eight  dollars  per  thousand 
in  Washington  for  tinted  facers.  They  have  nearly  always 
sold  on  a  parity  with  clay  bricks  in  markets  where  they  have 
been  introduced. 

Fire-resisting  Qualities.  —  The  following  extracts  regarding 
the  fire-resisting  qualities  of  sand-lime  brick  are  from  the  report 
made  by  Prof.  Ira  H.  Woolson  to  the  National  Association  of 
Manufacturers  of  Sand-lime  Products:* 

One  of  the  principal  objects  of  this  investigation  was  to 
determine  the  fire-resisting  properties  of  these  brick  by  a  prac- 
tical full-size  test  in  comparison  with  common  clay  brick.  For 
this  test  the  writer  used  the  partition  test  house  at  his  Fire-test- 
ing Station  at  Columbia  University. 

The  brick  were  laid  in  bands  about  14  inches  wide.  In 
order  that  each  variety  of  brick  might  be  subjected  to  the  same 
heat  conditions  as  far  as  possible,  only  half  of  a  band  was  laid 
on  the  same  level  in  the  wall.  The  other  half  was  placed  in 
some  other  position.  .  .  . 

It  was  also  decided  to  test  the  merits  of  lime  vs.  cement 
mortars  along  with  the  brick.  For  this  purpose  half  of  each 
wall  was  laid  with  the  different  mortars.  The  walls  were  17  days 
old  when  tested. 

Purpose  of  the  Test.  —  The  purpose  of  the  test  was  to  de- 
termine the  effect  of  a  continuous  fire  against  the  walls  for  two 
hours,  bringing  the  heat  up  gradually  to  1700°  F.  during  the 
first  half  hour  and  maintaining  an  average  of  1700  degrees  dur- 

*  See  "Tests  of  the  Strength  and  Fireproof  Qualities  of  Sand-lime  Brick," 
by  Ira  H.  Woolson,  Engineering  News,  June  14,  1906. 


MATERIALS    OF    FIRE-RESISTING    CONSTRUCTION      223 

ing  the  remainder  of  the  test.  Then  a  l|-inch  stream  of  cold 
water  to  be  thrown  against  the  .wall  for  three  minutes  at  hydrant 
pressure,  which  at  this  location  varies  from  25  to  30  pounds.  .  .  . 

Effect  of  the  Test.  —  Several  large  cracks  developed  in  both 
the  sand-lime  and  the  clay-brick  walls  during  the  test.  These 
were  no  worse  in  one  wall  than  in  the  other  and  were  expected, 
for  all  walls,  whether  brick  or  concrete.  It  was  not  apparent  that 
the  kind  of  mortar  had  any  effect  upon  .the  tendency  of  the  wall 
to  crack. 

A  furious  fire  was  maintained  for  the  allotted  time,  at  the 
expiration  of  which  the  water  was  applied  in  the  regulation 
manner.  With  the  exception  of  surface  deterioration  the  walls 
were  solid  and  in  good  condition.  After  they  were  cooled  the 
inside  course  of  each  wall  was  cut  through  and  specimens  of  each 
series  secured  for  examination  and  test.  This  opening  was  made 
at  the  middle.  It  was  about  3  feet  wide  and  extended  nearly 
across  the  building  vertically.  It  was  very  difficult  to  secure 
whole  bricks  owing  to  the  extreme  brittleness.  We  endeavored 
to  secure  two  samples  from  each  series  for  test  without  tearing 
down  the  whole  wall  and  in  most  cases  were  successful.  .  .  . 

In  general  the  bricks  were  affected  by  fire  about  half  way 
through.  They  were  all  brittle  and  many  of  them  tender  when 
removed  from  the  wall.  With  the  sand-lime  brick,  if  a  brick 
broke  the  remainder  had  to  be  chiseled  out  like  concrete,  whereas 
a  clay  brick  under  like  conditions  would  chip  out  easily.  The 
clay  brick  were  so  brittle  and  full  of  cracks  that  the  wall  could  be 
broken  down  without  trouble.  The  sand-lime  bricks  adhered 
to  the  mortar  better,  were  cracked  less  and  were  not  so  brittle. 
These  conditions  made  their  removal  much  more  difficult.  They 
will  doubtless  get  harder  as  the  water  dries  out  of  them. 

The  clay  brick  cracked  and  spalled;  the  sand-lime  brick 
washed  away  on  the  surface  and  became  tender.  It  was  difficult 
to  find  a  clay  brick  that  was  not  cracked  in  two  or  more  pieces 
as  they  lay  in  the  wall,  but  there  were  many  sand-lime  bricks 
that  were  apparently  free  from  cracks;  however,  they  were  very 
apt  to  break  in  prying  out.  The  half  bricks  from  the  clay  wall 
when  struck  with  similar  sand-lime  brick  would  in  most  cases 
shatter  first. 

Subsequent  Note.  —  Since  this  paper  was  written  a  large  part 
of  both  the  walls  submitted  to  the  fire  test  have  been  cut  out, 
and  it  is  my  candid  opinion  that  the  sand-lime  bricks  were  in 
much  better  condition  than  the  clay  bricks.  This  opinion  is 
emphatically  endorsed  by  the  brick  masons,  who  did  the  work, 
also  by  others  who  examined  the  walls. 

Pressed-  or  Face-Brick.  —  Experimental  tests  and  practical 
tests  furnished  by  burned  buildings  seem  to  offer  decidedly 
conflicting  testimony  as  to  the  ability  of  pressed-brick  to  resist 
fire.  Thus  in  the  United  States  Geological  Survey  tests  of 
building  materials,  "the  hydraulic-pressed  brick  withstood  the 


224         FIRE    PREVENTION    AND    FIRE    PROTECTION 

test  very  well.  No  damage  was  apparent  after  the  firing  and 
before  the  water  was  applied,  and,  although  a  number  of  the 
bricks  were  cracked,  70  per  cent,  of  them  were  found  to  be  sound 
after  quenching."  In  this  test  no  spalling  of  the  bricks  was 
observed.  This  result  is  very  different  from  the  behavior  of 
pressed-brick  in  the  Baltimore  fire,  where  considerable  damage 
resulted  in  many  instances.  In  the  Union  Trust  Company's 
Building- many  quoins  and  raised  belt  courses  of  face-brick  were 
split  off  even  with  the  face  of  the  wall,  and  in  the  Maryland  Trust 
Company's  Building  many  of  the  face-brick  piers  in  the  upper 
stories  were  badly  scaled  over  considerable  areas.  Damage  to 
face-brick  at  the  corners  of  window  reveals,  etc.,  was  very 
common. 

The  difference  between  the  results  of  these  experimental  and 
actual  tests  would  seem  to  be  this,  —  the  experimental  test 
quoted  above  was  made  on  a  perfectly  flush  panel  about  six 
feet  by  nine  feet  in  size,  built  into  a  surrounding  frame  of  fire- 
brick, thus  having  no  exposed  edges;  —  whereas  practical  use 
in  buildings  requires  not  only  corners  at  openings,  but  also  piers 
which  may  be  subjected  to  great  heat  on  three  sides  at  the  same 
time. 

In  Mr.  Himmelwright's  report  on  the  San  Francisco  fire,  the 
following  conclusions  are  given  regarding  face-brick: 

Various  varieties  of  brick  were  also  used  in  the  facades. 
A  silica  brick,  stamped  with  a  diamond,  enclosing  the  letter  S, 
proved  very  refractory  and  gave  excellent  results.  The  buff 

Eressed  terra-cotta  brick,  next  to  the  silica  brick,  developed  the 
est  fire  resistance.     The  common  red  pressed-brick  was  also 
used  and  gave  good  results.* 

No  better  material  for  fire-resisting  wall  construction  —  that 
is,  of  a  finished  nature  —  can  be  selected  than  pressed-brick, 
but  minimum  damage  requires  the  use  of  plain  unbroken  sur- 
faces, with  rounded  corners  at  all  salient  angles. 

Glazed  Brick.  —  The  scaling  of  glazed  brick  in  the  Baltimore 
fire  was  also  noticeable,  especially  in  courts  where  the  heat  was 
more  confined,  and  around  window  openings  where  draughts 
of  air  occurred.  Similar  damage  was  frequent  in  the  San 
Francisco  buildings. 

*  See  "The  San  Francisco  Earthquake  and  Fire,"  by  A.  L.  A.  Himmel- 
wright,  C.  E.,  published  by  the  The  Roebling  Construction  Company. 


MATERIALS   OF   FIRE-RESISTING   CONSTRUCTION      225 

Architectural  Terra-Cotta.  —  Method  of  Manufacture.  — 
Primarily,  architectural  terra-cotta,  as  the  name  implies,  is  a 
burnt-clay  material,  but  it  differs  from  brick  in  that  it  is  made 
of  two  or  more  clays,  selected  for  various  properties,  thoroughly 
mixed  together  in  definite  proportions  with  grit  (ground  terra- 
cotta previously  burned).  Furthermore,  it  is  not  a  stock  mate- 
rial like  brick.  Every  piece  is  made  entirely  by  hand  according 
to  the  architect's  design,  and  is  intended  to  occupy  a  certain 
place  in  the  proposed  building. 

Very  great  development  in  architectural  terra-cotta  has  taken 
place  in  comparatively  recent  years.  Instead  of  being  dependent 
now  upon  the  natural  burnt-clay  colors,  it  may  be  made  in  an 
endless  variety  of  soft  or  brilliant  colors.  The  clay  body  varies 
only  slightly  in  color  tone  for  the  different  colors.  The  effect 
is  obtained  by  glazing  or  covering  the  body  with  a  color  slip 
which  is  thoroughly  incorporated  with  the  body  during  the 
process  of  firing  in  the  kiln.  The  highest  order  of  ceramic 
chemical  knowledge  is  necessary  to  bring  these  results  about 
successfully. 

Another  great  development  is  owing  to  the  improved  me- 
chanical accuracy  and  efficiency  of  architectural  terra-cotta. 
While  formerly  it  was  used  exclusively  for  the  decorative  features 
of  buildings,  because  easily  modeled,  now  entire  facades  (includ- 
ing some  of  the  tallest  skyscrapers)  are  made  of  architectural 
terra-cotta  alone,  both  the  wall  faces  and  the  decorative  members. 

Polychrome  terra-cotta  or  faience  is  the  most  recent  develop- 
ment and  is  coming  into  ever  increasing  popularity  for  brighten- 
ing the  fagade  of  a  building,  or  for  interior  decoration. 

However,  few  changes  have  taken  place  in  the  methods  of 
manufacture  except  for  minor  differences  in  the  type  of  machinery 
used,  and  the  added  equipment  necessary  for  the  application  of 
color.  In  the  east  the  clay  comes  largely  from  New  Jersey, 
in  some  cases  from  banks  that  were  operated  thirty  years  ago. 
At  the  factory  it  is  mixed  and  ground  in  large  revolving  "wet 
pans"  and  forced  through  a  pug  mill.  Enough  water  is  added 
in  the  mixing  process  to  make  it  plastic  and  easily  modeled. 
Separate  models  are  made  for  each  piece  of  differently  shaped 
terra-cotta,  and  plaster  moulds  are  taken  from  these  models. 
When  a  great  number  of  pieces  of  the  same  size  and  shape  are 
needed,  several  moulds  are  necessary,  but  for  an  ordinary  run 
of  from  50  to  100  similar  pieces,  one  mould  is  sufficient.  The 


226         FIRE   PREVENTION   AND   FIRE   PROTECTION 

terra-cotta  is  pressed  by  hand  into  the  mould,  left  for  a  while  to 
dry  and  stiffen,  and  is  then  turned  out  and  finished  by  hand. 
After  drying  a  while  in  a  slightly  heated  atmosphere,  it  is  taken 
to  the  dryers  where  the  temperature  is  about  150  degrees.  When 
bone  dry  it  is  taken  to  the  spraying  room  where  the  color  is 
pneumatically  applied.  In  the  case  of  polychrome,  this  is  done 
with  painstaking  care.  It  is  then  loaded  in  muffle  kilns  where 
the  heat  passes  through  double  walls  so  that  the  flame  and  gas 
may  not  come  into  direct  contact  with  the  material.  The  door 
of  the  kiln  is  sealed  up  and  the  heat  gradually  raised  to  a  tem- 
perature approximating  2300°  F.  At  this  point  terra-cotta  is 
white-hot  and  translucent,  and  the  color  coat  or  glaze  fluxes 
together  in  the  expected  chemical  reaction.  The  kiln  is  then 
gradually  cooled.  The  time  is  equally  divided  between  raising 
the  heat  gradually,  keeping  the  heat  at  the  highest  desired  point, 
and  cooling  gradually.  When  the  kiln  is  unloaded  the  work 
is  laid  out  on  the  fitting  shop  floor,  fitted  in  sections,  carefully 
measured,  and  in  the  better  class  of  factories  the  joints  are 
ground  by  machinery  to  accurate  alignment. 

Terra-cotta  in  the  finished  state  is  very  hard,  and  owing  to 
the  glaze  is  absolutely  impervious.  When  properly  constructed, 
it  will  bear  any  necessary  amount  of  compression. 

Terra-cotta  construction  differs  to  some  extent  from  the 
method  of  construction  employed  for  other  structural  materials, 
as  is  pointed  out  in  more  detail  in  Chapter  XX.  Before  the 
terra-cotta  is  made,  the  manufacturer  redraws  the  architect's 
plans  to  J-inch  scale,  showing  the  construction  in  complete 
detail,  with  bonding,  anchoring  and  jointing.  These  drawings 
are  subject  to  the  architect's  approval.  With  every  shipment, 
complete  setting  drawings  are  supplied  for  the  builder. 

A  very  high  grade  of  labor  is  employed  in  the  modeling  de- 
partment, one  or  two  able  sculptors  usually  being  in  charge. 

Durability.  —  As  to  its  durability,  Mr.  F.  E.  Kidder  in  his 
" Building  Construction'7  states  that 

In  Europe  there  are  numerous  examples  of  architectural 
terra-cotta  which  have  been  exposed  to  the  weather  for  three  or 
four  centuries  and  are  still  in  good  condition,  while  stonework 
subjected  to  the  same  conditions  is  more  or  less  worn  and  decayed. 

When  properly  made,  ornamental  terra-cotta  is  impervious 
to  moisture  or  to  the  disintegrating  action  of  frost.  The  glazed 
skin  produced  by  the  vitrification  of  the  mass  causes  the  material 


MATERIALS   OF   FIRE-RESISTING    CONSTRUCTION      227 

successfully  to  resist  climatic  effects,  even  under  the  severe 
conditions  common  to  the  United  States. 

Fire-resisting  Properties.  —  The  behavior  of  architectural 
terra-cotta  under  fire  test  in  the  Baltimore  and  San  Francisco 
fires  was  very  disappointing.  Numerous  accounts,  of  the  former 
fire  especially,  have  dwelt  upon  the  apparently  excellent  showing 
made  by  this  material.  From  the  street,  or  from  a  superficial 
examination  only,  many  brick  and  terra-cotta  walls  appeared 
to  be  little  injured,  when,  in  fact,  the  terra-cotta,  although  re- 
taining its  form,  was  quite  destroyed.  Thus  in  several  buildings 
where  walls  of  this  character  seemed  to  have  sustained  but 
trifling  injury,  the  adjusted  fire  loss  and  actual  reconstruction 
told  a  far  different  story.  Brick  walls  with  terra-cotta  trim 
were  entirely  replaced  in  the  Union  Trust  Company's  and  Herald 
Buildings  (having  been  condemned  by  the  city  authorities  in 
the  former  case),  while  in  the  Calvert  Building  the  adjusted  loss 
on  ornamental  terra-cotta  was  73.5  per  cent.,  in  the  Equitable 
Building  70  per  cent.,  and  in  the  Maryland  Trust  Company's 
Building  75  per  cent. 

The  report  of  the  National  Fire  Protection  Association  states 
that  "Good  terra-cotta  wall  trim,  when  reasonably  plain  and 
free  from  ornamentation  involving  irregular  shapes,  is  superior 
to  stone  but  not  so  desirable  as  brick."  This  carefully  guarded 
statement  on  the  part  of  the  underwriters  who  framed  that 
report  was  further  justified  by  the  showing  made  by  architectural 
terra-cotta  in  the  San  Francisco  conflagration. 

Of  the  terra-cotta  fronts,  most  were  destroyed,  for  instance 
the  Bullock  and  Jones  Building.  Terra-cotta  brick  spalled 
everywhere.  .  .  .  Either  stone,  brick  or  terra-cotta  was  used 
around  windows,  and  here  the  damage  was  the  worst.  In  rela- 
tion to  this  it  may  be  said  that  terra-cotta  is  deceptive,  in  that 
it  retains  its  form  after  being  destroyed.  Many  fronts,  appar- 
ently in  good  order,  must  be  removed.  In  the  Mills  Building 
there  was  hardly  a  window  opening  in  which  the  terra-cotta  sills, 
jambs  and  heads  were  not  badly  cracked.  From  the  street, 
they  had  the  appearance  of  being  in  good  order.* 

Improvements  Needed  in  Manufacture  and  Use.  —  Injury  by 
fire  to  architectural  terra-cotta  results  from  either:  (a)  direct- 
flame  action,  (6)  shattering  due  to  more  or  less  sudden  changes 

"The  Effects  of  the  San  Francisco  Earthquake  and  Fire  on  Engineering 
Constructions,"  Transactions  Am.  Soc.  C.  E.,  Vol.  L1X,  p.  238. 


228         FIRE   PREVENTION   AND   FIRE   PROTECTION 

in  temperature,  or  (c)  mechanical  damage  caused  by  poor  con- 
struction or  by  the  expansion  of  covered  steel  members. 

Slight  damage  usually  results  from  the  first  and  second  causes, 
except  where  the  material  is  highly  ornamented,  or  where  manu- 
factured with  too  thin  surfaces  or  dividing  webs.  To  be  efficient 
under  fire  test,  architectural  terra-cotta  should  be  of  as  plain  a 
surface  and  design  as  possible,  and  with  no  thickness  of  material 
less  than  one  and  one-half  inches. 

By  far  the  largest  part  of  damage  to  this  material  is  due  to 
the  third  cause,  viz.,  its  method  of  use.  Repeated  experiences 
in  Baltimore  buildings  showed  that  the  expansion  of  steel  or 
cast-iron  mullions,  reinforcing  members,  or  steel  spandrel  sec- 
tions cracked  and  destroyed  the  surrounding  terra-cotta  blocks 
in  window  mullions,  heads,  and  sills,  and  the  window  damage 
quoted  above  as  occurring  in  the  Mills  Building  in  San  Francisco 
was  undoubtedly  largely  due  to  this  same  cause. 

The  following  opinion  of  the  architect  of  the  before-mentioned 
Calvert  Building  is  both  interesting  and  instructive: 

I  have  always  been  a  strong  advocate  of  terra-cotta,  not  as 
a  cheap  substitute  for  stone,  but  as  a  legitimate  building  material 
worthy  of  an  artistic  expression  of  its  own,  and  have  watched  the 
development  of  its  manufacture  with  the  greatest  interest.  Here 
I  thought  we  had  the  real  fireproof  material;  and  though  it  has 
stood  the  fire  better  than  any  of  the  building  stones,  it  has  failed 
to  measure  up  to  expectations.  This  is  not  wholly  the  fault  of 
the  material;  its  failure  is  due  in  part  to  our  method  of  con- 
struction. Thin  shells  of  terra-cotta  suspended  from  steel  sup- 
ports or  resting  on  exposed  ironwork  are  bad  from  an  aesthetic 
point  of  view,  and  very  bad  when  subjected  to  intense  heat. 
The  results  of  the  fire  convince  me  that  it  is  most  important  to 
make  architectural  terra-cotta  self-supporting,  and  to  eliminate 
as  far  as  possible  the  use  of  steel  and  iron  in  connection  with  it. 
The  sills  and  key-blocks  on  the  Calvert  Building  were  evidently 
crushed  by  the  expansion  of  the  cast-iron  mullions. 

An  interesting  fact  in  regard  to  the  Calvert  Building  is 
that  on  the  west  side,  where  the  terra-cotta  was  gradually  heated 
by  the  approaching  fire,  the  damage  is  slight ;  and  on  the  oppo- 
site, or  east  side ,  where  the  walls  were  chilled  by  the  cold  weather 
then  prevailing,  and  subject  to  sudden  and  fierce  heat  through 
the  windows  of  the  burning  building,  the  terra-cotta  is  badly 
damaged.* 

Other  points  in  connection  with  the  proper  use  of  this  material 
are  given  in  Chapter  XX. 

*  See  Joseph  Evaris  Sperry  in  the  Brickbuilder,  Baltimore  Fire  extra  num- 
ber, March,  1904. 


MATERIALS    OF   FIRE-RESISTING    CONSTRUCTION      229 

Structural  Terra-cotta.  —  The  terra-cotta  used  for  struc- 
tural purposes,  as  for  floor  arches,  column  protections,  and  for 
partitions,  is  either  " porous,"  "semiporous,"  or  "hard  burned," 
according  to  the  method  of  manufacture.  Porous  terra-cotta 
is  also  called  terra-cotta  lumber,  cellular  pottery,  soft  tile, 
porous  tile,  etc.,  while  hard  burned  terra-cotta  is  sometimes 
called  fire  clay,  tile,  hard  tile  or  dense  tile. 

Manufacture  of  Porous  Terra-cotta.  —  Porous  terra-cotta 
is  made  by  mixing  sawdust  with  pure  clay,  which  is  then  moulded 
and  burned  under  a  high  heat,  causing  the  combustion  of  the 
sawdust,  and  leaving  the  material  in  a  porous  state,  thereby 
reducing  the  weight  of  the  original  mass.  The  factories  or 
places  of  manufacture  are  usually  located  near  an  adequate 
supply  of  clay  of  the  required  properties. 

Mixing.  —  Plastic  clay  is  dug  from  the  "clay  bank,"  taken  to 
the  clay  house,  where  it  is  broken  into  pieces  as  small  as  prac- 
ticable by  hand  labor,  and  mixed  with  coarse  soft-wood  sawdust 
(pine  or  spruce),  one  volume  of  sawdust  to  two  volumes  of  clay. 
During  the  wet  season  this  mixture  is  tempered  with  a  quantity 
of  either  dry  clay  or  crushed  brick  to  prevent  unusual  shrinkage 
due  to  the  large  volume  of  water  in  the  clay.  The  mixture  is 
passed  through  a  disintegrator,  consisting  of  an  endless  worm 
or  cutter  revolving  in  a  sloping  trough,  which  thoroughly  cuts 
up  all  the  clay  before  conveying  it  to  the  "pug-mill."  The 
"pug-mill"  consists  of  a  hopper  at  the  top,  leading  down 
between  a  set  of  two  corrugated  rolls  revolving  in  different 
directions.  These  corrugations  crush  the  clay  between  them, 
allowing  stones  of  about  one  inch  diameter  or  less  to  pass 
through  whole.  Large  stones  are  separated  from  the  clay  and 
are  delivered  to  the  refuse  box.  A  second  and  lower  set  of 
smooth  rolls,  revolving  in  the  same  directions  as  the  first  set, 
crushes  the  clay  and  small  stones  into  a  thoroughly  mixed  and 
tempered  state,  distributing  the  sawdust  through  the  mass  very 
evenly.  In  dry  seasons  water  may  be  added  in  required  quan- 
tity at  the  hopper  to  produce  a  plastic  mass. 

From  the  pug-mill  base  a  conveyor  receives  the  clay  and 
carries  it  to  the  machine  which  forms  the  tile.  These  conveyors 
have  different  forms,  but  are  commonly  of  either  a  continuous 
belting  of  rubber  or  a  series  of  slats  in  the  form  of  a  belt. 

Dry-pan  Method.  —  In  a  large  portion  of  the  states  in  which 
clay  deposits  are  utilized,  some  of  the  clays  are  termed  "Shale 


230         FIRE   PREVENTION   AND    FIRE   PROTECTION 

Clays,"  that  is,  the  geological  formation  is  indurated  clay  or 
shale.  This  shale  as  found  in  the  mine  or  bank  does  not  become 
plastic  until  it  has  been  ground  to  a  dust,  screened  through  a 
series  of  screens,  and  finally  mixed  with  water  to  obtain  a  proper 
consistency  and  plasticity. 

This  result  is  obtained  by  the  use  of  special  machines,  namely, 
the  dry  pan,  and  the  wet  pan  or  pug-mill. 

Dry  Pan.  —  The  dry  pan  consists  of  a  cast-iron  pan  varying 
from  5  to  9  feet  in  diameter.  This  pan  revolves  at  a  speed  vary- 
ing from  30  to  40  revolutions  per  minute.  Part  of  the  bottom 
of  this  pan,  nearest  the  center,  is  made  up  of  chilled  plates,  the 
balance  of  the  bottom  being  made  up  of  perforated  grates. 
Resting  on  the  solid  portion  of  the  pan  are  two  heavy  mullers, 
weighing  from  1500  to  2000  pounds  each.  These  mullers  or 
wheels  are  suspended  on  a  horizontal  shaft,  which  is  supported 
by  two  "  A"  frames  (one  at  each  end),  and  on  which  these  mullers 
revolve.  When  the  pan  is  put  in  operation,  the  pan  revolves. 
This  gives  to  the  mullers  a- rotary  motion  around  the  horizontal 
shaft.  A  certain  amount  of  shale  is  thrown  in  the  pan.  By 
means  of  scrapers  fastened  at  a  suitable  angle,  the  material  to 
be  ground  is  thrown  under  the  mullers.  By  the  action  of 
the  centrifugal  force,  the  shale  is  thrown  towards  and  over  the 
screening  plates,  and  what  is  sufficiently  fine  to  go  .through  the 
perforations,  drops  below  and  is  then  conveyed  over  revolving 
or  other  screens,  and  the  tailings  are  allowed  to  go  back  for  further 
grinding. 

A  wet  pan  is  exactly  the  same  as  a  dry  pan  in  its  construction. 
The  only  difference  is  that  the  bottom  of  the  pan  is  solid  through- 
out, and  the  charge,  when  sufficiently  ground,  is  unloaded  either 
by  hand  or  automatically. 

Therefore  the  dry  pan  is  used  for  grinding  the  shale  and 
preparing  it  for  the  wet  pan.  The  wet  pan  is  used  for  mixing 
and  tempering,  and  is  one  of  the  best  devices  known  for  this 
purpose. 

The  "tile  machines,"  or  machines  which  shape  the  stream  of 
clay,  are  of  various  patterns,  each  of  which  has  points  which 
commend  it,  but  the  natures  of  the  clay,  according  to  locality, 
require  different  machines.  The  machine  takes  the  clay,  and 
by  different  means  again  works  the  mass,  tempering  it  by  a  set 
of  revolving  knives  into  a  sufficiently  soft  and  plastic  state  to  al- 
low the  required  shaping.  In  forming  the  blocks  these  machines 


MATERIALS    OF    FIRE-RESISTING    CONSTRUCTION      231 

are  operated  differently,  according  to  pattern  of  machine  used. 
Some  force  the  stream  of  clay  by  means  of  a  hinged  cam.  This 
cam  is  moved  forward  or  backward  by  another  cam  fastened 
to  the  center  revolving  shaft,  and,  coming  in  contact  with  the 
hinged  cam,  forces  the  clay  before  it.  Others,  in  the  plunger 
style,  move  the  clay  by  means  of  a  piston  head,  operated  directly 
from  an  independent  cylinder.  In  either  case  the  clay  is  forced 
from  the  interior  of  the  machine  through  the  "form,"  which  is 
made  of  two  independent  parts  —  the  "plugs"  or  dies,  which  are 
within  the  machine  —  and  the  "form"  proper,  which  constitutes 
the  outlet. 

The  plugs  are  made  of  metal,  and  are  of  the  exact  shape  and 
relative  position  of  the  voids  in  the  tile  block.  They  are  sta- 
tionary, with  their  faces  placed  a  few  inches  inside  the  final 
form.  As  the  clay  is  pressed  by  the  plungers  against  the  faces 
of  the  plugs  it  is  perforated,  thus  forming  the  voids  in  proper 
position  for  the  final  blocks.  After  passing  the  plugs  the  clay 
has  no  external  shape,  until,  by  the  continued  operation  of  the 
plunger,  the  clay  is  forced  from  the  form  or  die  placed  at  the 
outlet  of  the  machine,  thus  giving  the  required  exterior  shape 
of  the  manufactured  product. 

This  finished  shape  is  forced  out  continuously  onto  the  cut- 
ting table,  which  is  usually  composed  of  sets  of  rolls  or  plates, 
well  greased  to  prevent  adhesion  and  friction,  which  would 
have  a  tendency  to  deform  the  block.  Above  the  cutting  table 
are  the  cutters,  which  are  of  various  styles,  fastened  in  many 
ways,  but  on  the  general  principle  of  an  "arbor"  or  light  frame- 
work which  spans  the  table,  the  opposite  sides  being  connected 
by  wires  or  knives.  This  frame  is  moved  up  and  down  by 
means  of  a  lever  controlled  by  the  operator,  who  cuts  the  moving 
mass  of  clay  into  blocks  of  the  required  shape  and  length.  The 
wires  may  be  parallel,  as  for  filler  blocks,  or  made  to  cut  the 
form  of  a  key. 

Special  Forms.  —  The  manufacture  of  special  forms  of  terra- 
cotta, although  not  differing  widely  from  the  ordinary  shapes, 
compels  some  special  manipulation  —  as,  for  instance,  in  making 
skewbacks.  The  side  construction  skewback,  when  run  from 
the  forcing  machine,  comes  out  with  the  shape  of  the  beam  al- 
ready formed,  while  in  the  case"  of  the  end-construction  skew- 
back,  the  seat  of  the  skew  has  to  be  formed  by  hand  after  it 
has  been  run  trom  the  machine.  It  is  cut  to  the  shape  desired 


232         FIRE    PREVENTION    AND    FIRE    PROTECTION 

over  a  templet  and  by  means  of  a  wire  fastened  to  a  bow.  Other 
products,  such  as  rabbeted  ceiling  or  roofing  blocks,  have  to 
have  the  rabbet  formed  in  a  like  manner  by  hand  where  the 
blocks  are  over  13  or  14  inches  in  width,  because  the  form  or 
mouth  of  the  machine  cannot  produce  a  wider  stream  of  clay. 
Such  blocks  can  be  made  complete  by  the  forming  machine  when 
not  over  the  above  width,  as  in  this  case  the  voids  and  rabbets 
can  be  parallel ;  but  in  wider  blocks  the  voids  run  at  right  angles 
to  the  rabbets,  so  that  the  latter  must  be  hand-formed.  For 
circular  column  covering  blocks  a  form  of  the  same  shape  is 
usually  placed  on  the  cutting  table,  onto  which  the  clay  is  forced 
when  coming  from  the  machine.  This  style  of  block  is  usually 
dried  standing  on  end  to  prevent  deformation  by  sagging. 

Drying.  —  From  the  cutting  table  the  blocks  are  placed  upon 
" pallets,"  consisting  of  light  open  wooden  gratings,  which, 
when  filled,  are  stacked  upon  cars  made  of  light  metal  framing 
with  adjustable  racks  to  receive  the  pallets  in  such  manner  that 
the  blocks  just  clear  each  other  and  permit  the  free  circulation 
of  air  over  the  entire  area  of  the  blocks.  The  cars  are  then  run 
into  the  "dry  tunnels,"  which  are  heated  by  means  of  steam 
coils  to  a  temperature  of  about  150  to  200  degrees  for  a  space 
of  time\arying  according  to  the  nature  of  the  material  fcand  the 
size  of  the  blocks,  usually  taking  from  two  to  three  days.  At 
the  end  of  this  time  the  blocks  are  sufficiently  dry  to  permit 
handling. 

The  blocks  are  next  stacked  in  kilns,  which  are  of  various 
styles,  the  " down-draft"  pattern  being  usually  considered  the 
most  satisfactory. 

The  "Down-draft"  Kiln  consists  of  a  circular  vaulted  cham- 
ber, ordinarily  30  to  35  feet  inside  diameter,  and  8  to  10  feet 
high  from  the  bottom  of  the  kiln  to  the  skewback  of  the  vaulted 
arch.  The  spring  of  this  arch  is  generally  one-fourth  the  diam- 
eter. The  flow  of  the  kiln  is  double.  The  upper  floor  is  per- 
forated. A  series  of  furnaces  are  placed  around  the  kiln  at  the 
floor  level.  The  heat  from  these  furnaces  is  conveyed  upward, 
strikes  the  vaulted  part  (which  is  known  as  the  " crown").  At 
that  point  the  heat  spreads,  travels  through  the  ware  downwards, 
and  finds  its  egress  to  a  stack  through  the  perforated  floor. 

The  temperature  required  to  properly  burn  the  material 
varies  from  2000°  to  2500°  F.,  according  to  the  refractory  quality 
of  the  clay  used  in  the  manufacture. 


MATERIALS    OF    FIRE-RESISTING    CONSTRUCTION      233 

"Continuous  Kiln"  —  Besides  the  down-draft  kiln  described 
above,  the  use  of  the  so-called  " continuous  kiln"  has  been 
adopted  of  late  years,  with  very  satisfactory  results. 

The  main  features  of  this  kiln  are  the  entire  utilization  of 
the  heat  units  contained  in  the  coal  used  and,  also,  the  possi- 
bility of  using  cheaper  fuel.  The  heat  obtained  from  the  coal 
travels  from  one  chamber  to  another,  so  that,  by  means  of  dam- 
per regulation,  the  fuel  is  utilized  and  none  is  lost.  The  per- 
centage of  coal  used  in  such  kiln  is  greatly  .reduced,  and  much 
less  than  in  the  ordinary  down-draft  kiln. 

On  starting  heat,  the  first  thing  done  is  to  " water  smoke"  the 
kiln,  the  purpose  being  to  remove  the  surplus  moisture  slowly, 
in  order  to  prevent  great"  crackling  of  the  tiles.  This  is  done 
by  applying  a  slow  heat,  continuing  usually  from  twelve  to 
twenty-four  hours. 

After  being  thoroughly  fired  in  the  kiln,  the  tile  is  ready  for 
use.  The  sawdust  in  the  clay  is  entirely  consumed  during  the 
firing,  leaving  the  finished  product  in  a  finely  honeycombed 
state. 

If  the  clay  used  is  of  a  granular  nature,  the  combustible 
material  used  to  produce  the  porosity  should  be  of  but  slight 
quantity  in  comparison  with  the  total  bulk.  If  of  large  quan- 
tity, the  film  which  originally  encased  the  sawdust  or  other  com- 
bustible material  before  burning  is  so  light  that  when  burned 
it  leaves  the  finished  product  full  of  large  cells.  This  will  give 
an  insufficient  strength.  If  the  clay  is  of  a  fibrous  nature  it 
will  take  a  much  larger  quantity  of  sawdust,  and  a  much  stronger 
block,  comparatively,  will  be  produced.  It  is  generally  conceded 
that  fibrous  clay  makes  a  much  better  porous  material  than 
granular  clay.  These  factors  should  be  taken  into  consideration 
in  determining  the  texture  of  porous  material. 

Manufacture  of  Semi-porous  Terra-cotta.  —  The  manu- 
facture of  "semiporous"  terra-cotta  differs  from  that  of  porous 
terra-cotta  principally  in  the  composition  of  the  mixture.  To 
a  fair  quality  of  fire-clay,  containing  about  60  per  cent,  of  silica, 
is  added  a  certain  percentage  of  clean  calcine  fire-clay,  coarsely 
ground,  and  a  percentage  of  coarsely  ground  clean  bituminous 
coal.  This  mixture  is  thoroughly  tempered,  and  burned  to  the 
desired  shapes.  The  result  of  this  mixture  is  a  material  slightly 
more  porous  than  the  best  grade  of  fire-brick,  and  still  not  as 
soft  as  the  ordinary  porous  terra-cotta  made  with  sawdust.  It 


234         FIRE   PREVENTION   AND   FIRE   PROTECTION 

is  claimed  that  semiporous  tile  may  be  heated  to  a  temperature 
of  3500  degrees,  and  immersed  in  cold  water  at  that  temperature, 
without  cracking. 

Manufacture  of  Hard  Burned  Terra-cotta.  —  Hard 
burned  terra-cotta  or  ''dense  tiling"  is  made  of  natural  clays 
without  the  addition  of  any  combustible  material.  The  only 
ingredients  added  to  the  natural  clay  in  making  this  product 
are,  in  low  grades  of  clay,  crushed  brick  or  sand,  to  prevent 
abnormal  shrinkage.  During  manufacture  the  clay  is  subjected 
to  a  high  pressure  which  gives  the  material  a  dense  texture,  and 
great  strength  under  crushing  loads.  The  blocks  are  shaped  by 
the  forming  machine,  as  before  described,  and  they  are  burned 
in  kilns,  like  the  porous  product,  except  that  the  time  required 
for  burning  is  longer. 

If  the  material  is  quite  rough,  it  indicates  too  great  a  quantity 
of  sand,  which  produces  undesirable  brittleness.  No  dependence 
can  be  placed  on  a  test  of  strength  of  such  material.  If  clay 
with  an  excessive  quantity  of  sand  is  burned  at  a  low  heat,  it 
will  not  have  been  sufficiently  burned  to  fuse  or  unite  the  par- 
ticles of  sand,  thus  producing  a  weak  and  brittle  block.  If 
burned  at  a  high  heat,  sufficient  to  fuse  the  sand,  it  is  nearly, 
if  not  quite,  vitrified,  in  which  case  suction  is  almost  wholly 
destroyed.  Hence  a  hard,  rough  material  is  an  undesirable 
building  terra-cotta,  because  it  has  been  burned  either  too  much 
or  not  enough.  The  product  should  have  a  hard  but  smooth 
surface. 

Characteristics  of  Porous  and  Hard  Burned  Terra-cotta. 
—  Porous  terra-cotta  can  be  easily  cut,  and  there  are  grades 
soft  enough  to  allow  the  driving  in  of  nails  or  screws  for  receiving 
the  interior  trim  of  buildings,  when  so  desired,  or  for  fastening 
slates,  tiles,  etc.,  on  roofs.  These  soft  nailing  blocks  are  usually 
made  solid. 

The  quality  of  porous  material  may  be  ascertained  by  striking 
the  block  with  metal,  and  the  result  should  be  a  dull  ring.  If 
a  sound  is  produced  which  indicates  a  crack,  the  block  should 
be  condemned.  The  texture  of  the  material  can  generally  be 
determined  by  the  weight  of  the  block.  While  lightness  is  an 
advantage,  to  be  abnormally  light  is  an  indication  of  weakness. 

Hard  burned  terra-cotta  cannot  be  readily  cut,  but  must  be 
broken.  The  material  is  brittle,  and  is  liable  to  failure  under 
shocks.  In  cases  where  suddenly  applied  loads  are  expected, 


MATERIALS   OF   FIRE-RESISTING    CONSTRUCTION      235 

porous  material  should  be  used.  Under  static  loads,  hard 
terra- cotta  is  stronger  than  porous  terra-cot ta,  in  comparing 
equal  section  areas;  but  this  difference  is  largely  offset  by  the 
increase  in  thickness  of  the  webs  in  porous  blocks i< 

In  deciding  on  the  quality  of  hard  burned  terra-cotta,  the 
ring  should  be  true,  when  struck  with  metal,  but  the  material 
should  not  be  too  hard,  as  it  will  not  give  sufficient  suction  to 
the  mortar  used  in  the  joints  in  setting.  If  of  a  smooth  surface, 
the  suction  will  be  poor,  and  the  blocks  should  be  grooved  or 
"scored"  to  provide  a  key  for  the  mortar. 

Structural  Terra-cotta  vs.  Concrete.  —  No  other  materials 
employed  in  fire-resisting  construction  have  exhibited  such 
seemingly  contradictory  testimony  as  to  their  fire-resisting 
qualities  as  have  structural  terra-cotta  and  concrete.  Argu- 
ments and  examples  for  or  against  tile  and  concrete  could  easily 
fill  a  volume  of  large  size  —  hence  the  condensation  of  the 
ipros  and  cons  of  these  materials  within  the  limitations  of  a 
^handbook  is  exceedingly  difficult.  If  one  has  any  preconceived 
ibias  in  favor  of  either,  it  is  not  difficult  to  find,  from  recorded 
opinions  and  experiences,  data  sustaining  such  preferences. 
'Thus  both  the  Baltimore  and  San  Francisco  conflagrations  have 
afforded  great  diversity  of  opinion  regarding  concrete  vs.  terra- 
(cotta  floors,  column  protections,  etc.,  but  it  should  be  remem- 
ibered  that,  after  such  wide-spread  fires  in  numerous  buildings, 
.anyone  with  prejudices  in  favor  of  almost  any  material  or  con- 
istruction  can  readily  find  evidence  to  support  his  views. 

Therefore  no  attempt  will  here  be  made  to  discuss  the  fire- 
mesisting  qualities  of  tile  or  concrete  in  a  manner  at  all  exhaustive, 
tbut  attention  will  be  confined  to  some  of  the  more  important 
facts  which. bear  on  the  fire-resistive  qualities,  together  with 
important  tests  on  the  materials  as  such,  and  the  opinions  of 
some  recognized  authorities  who  have  had  exceptional  advan- 
tages in  comparing  the  actual  behavior  of  the  materials  under 
practical  fire  tests  in  buildings.  Much  additional  information 
concerning  the  use  or  record  of  these  materials  as  employed  in 
.special  constructive  features  will  be  found  in  discussions  of 
vfloor  systems  in  Chapters  XI  and  XVII  to  XIX  inclusive,  of 
column  protections  in  Chapter  XII,  of  partitions  in  Chapter 
XIII,  of  walls  in  Chapter  XX,  and  of  roofs  in  Chapter  XXI. 

Fire-resisting  Qualities  of  Structural  Terra-cotta.  —  In 
judging  of  the  efficiency  of  structural  terra-cotta  as  a  fire-resisting 


236         FIRE    PREVENTION   AND    FIRE   PROTECTION 

material  as  exhibited  in  actual  fires,  several  important  facts 
must  be  borne  in  mind,  namely,  the  behavior  of  the  ma- 
terial itself  regardless  of  other  structural  deficiencies  which 
may  have  affected  the  structure  studied,  —  the  kind  of  material 
used,  —  the  attendant  conditions  of  the  test,  —  the  adequacy, 
mass,  or  sufficiency  of  the  construction,  —  the  details  of  con- 
struction employed,  —  and  the  workmanship  exhibited  by  the 
construction.  Reference  to  the  fires  described  in  Chapter  VI 
will  show  that  each  and  all  of  these  conditions  contribute  to  the 
success  or  failure  of  the  fireproofing.  Thus,  serious  structural 
deficiencies  which  greatly  contributed  to  the  loss  sustained  by 
the  fire-proofing,  existed  in  the  first  fire  in  the  Home  Store 
Building  in  Pittsburgh  as  regarded  the  roof  tank,  and  in  the 
Roosevelt,  Equitable  and  Parker  Buildings,  in  all  of  which  cast- 
iron  columns  were  used. 

The  conditions  of  test  were  unsatisfactory  in  many  of  the 
lower  buildings  in  the  Baltimore  fire,  and  also  unsatisfactory  in 
a  measure  in  all  of  the  San  Francisco  buildings  on  account  of 
the  undetermined  damage  due  to  the  earthquake  shocks,  es- 
pecially in  the  loosening  of  mortar  joints,  etc. 

The  kind  of  terra-cotta  employed  is  an  essential  factor.  Thus 
the  first  fire  in  the  Home  Store  Building  involved  hard  burned 
material,  and  the  results  were  poor.  The  showing  in  the  Home 
Office  Building,  and  in  the  second  fire  in  the  Home  Store  Build- 
ing, involved  semiporous  material,  and  the  showing  was  excellent. 

As  regards  adequacy,  or  the  sufficiency  of  material,  thick  webs 
of  porous  or  semiporous  floor-arch  blocks  stood  up  exceedingly 
well  in  the  Merchants  National  Bank  and  in  the  Chesapeake 
and  Potomac  Telephone  Company's  Building  in  Baltimore,  also 
in  the  Calvert  Building;  while  inadequacy  of  material  resulted 
in  dire  ruin  in  the  Equitable  and  Parker  Buildings.  Details 
of  construction  were  poor  in  the  Athletic  Club  and  Home  Life 
Buildings,  besides  many  cases  in  Baltimore.  The  record  of 
the  terra-cotta  test  was  correspondingly  poor. 

Poor  workmanship  was  much  in  evidence  in  both  the  Balti- 
more and  San  Francisco  fires,  and  the  fact  contributed  in  no 
little  measure  to  the  judgment  passed  on  materials. 

Taking,  then,  all  of  these  facts  into  consideration,  the  author 
considers  that  the  following  deduction  is  warranted  regarding 
the  fire  resistance  of  structural  terra-cotta;  that  porous  or  even 
semiporous  tile  can  and  generally  does  withstand  any  reasonable 


MATERIALS    OF    FIRE-RESISTING    CONSTRUCTION      237 

0 

fire  and  water  test,  provided  that  the  material  is  of  sufficient 
thickness  or  mass,  and  used  in  an  intelligent  manner. 

Hard  Burned  vs.  Porous  Terra-cotta.  —  The  tests  made 
in  Denver,  Colo.,  in  1890  (see  Chapter  XVII),  would  seem  con- 
clusive as  to  the  relative  values  of  porous  and  hard  burned 
terra-cot  ta  under  the  action  of  fire  and  water,  but  the  latter 
material  is  still  extensively  employed,  although  many  fires  and 
tests  since  1890  have  fully  confirmed  the  results  of  the  Denver 
tests. 

Hard  burned  terra-cotta  as  a  heat  insulator  depends  for  value 
entirely  upon  its  cellular  structure,  protection  being  afforded 
only  by  the  non-heat-conducting  air  spaces.  The  material 
itself  conducts  heat  much  more  readily  than  the  porous  kind. 
To  be  efficient,  therefore,  the  air  spaces  in  hard  burned  tile  must 
be  of  adequate  size  and  number  to  insulate  the  material  to  be 
protected.  When  cooled  by  water,  sudden  contraction  is  liable 
to  occur,  thereby  cracking  the  blocks.  If  made  of  a  good  re- 
fractory clay,  blocks  with  two  or  more  air-spaces  are  very  liable 
to  have  the  outer  webs  destroyed  under  this  action,  as  was  well 
illustrated  by  the  hard-tile  floor  arches  in  the  first  Home  Store 
Building  fire,  and  in  many  buildings  in  San  Francisco.  This 
was  due  to  the  inability  of  the  material  to  withstand  the  inequali- 
ties of  expansion  and  contraction  caused  by  the  heating  of  one 
side  of  the  arches  only.  The  blocks  usually  break  first  in  the 
corners,  because  the  strain  is  greatest  there,  and  the  tile  weakest. 
The  strain  is  greatest  in  the  corners  because  the  expansion  of 
the  one  side  tends  to  shear  it  from  the  adjoining  sides,  and  it  is 
weakest  in  the  corners  because  if  there  is  any  initial  stress  in 
the  material,  it  would  more  naturally  occur  there  than  elsewhere. 

Even  if  not  cooled  with  water,  other  fires  have  shown  that 
hard  burned  terra-cotta  will  crack  and  fall  to  pieces  under 
severe  heat  alone.  This  was  demonstrated  in  the  Schiller 
Theater  fire  in  Chicago. 

Porous  Terra-cotta  is  non-heat-conducting  in  itself,  without 
reference  to  its  form.  It  is  made  in  solid  as  well  as  in  hollow 
forms.  The  best  products  *of  a  porous  nature  have  resisted  fire 
and  water  far  better  than  the  best  hard  tile.  For  column  and 
girder  protections,  where  the  blocks  do  not  carry  loads,  the 
porous  material  is  very  generally  used,  but  in  floor  construction 
many  architects  prefer  to  use  the  hard  burned  variety  on  account 
of  its  greater  strength  and  cheaper  price. 


238         FIRE    PREVENTION    AND    FIRE    PROTECTION 

% 

Semiporous  Terra-cotta  is  largely  used.  It  is  stronger  than 
porous  tile,  and  less  liable  to  crack  than  hard  tile. 

Structural  Terra-cotta  in  Baltimore  Fire.  —  Captain 
John  Stephen  Sewell,  U.  S.  A.,  in  his  report  on  the  Baltimore 
fire,  stated  that 

Hollow  terra-cotta  undergoes  no  molecular  change,  if  of 
tough  and  refractory  clay;  suffers  large  percentage  of  loss  in  its 
commercial  forms  owing  to  mechanical  failure  under  stresses 
due  to  expansion  and  contraction.  If  made  porous,  of  good 
clay,  with  minimum  thickness  of  material  not  less  than  If  inches, 
would  probably  be  about  equal  to  brickwork. 

The  report  of  the  National  Fire  Protection  Association  on  the 
Baltimore  fire  severely  criticizes  the  showing  made  by  structural 
terra-cotta  in  those  buildings,  but  as  such  criticisms  particularly 
apply  to  the  material  as  used  in  floor  arches,  they  are  more  prop- 
erly considered  in  connection  with  tests  of  hollow  tile  floors  in 
Chapter  XVII. 

Structural  Terra-cotta  in  San  Francisco  Fire.  —  The 
uncertainty  of  the  San  Francisco  experience  as  regards  the  fire 
test  of  terra-cotta  has  previously  been  pointed  out.  In  addition 
to  the  unknown  damage  which  may  have  been  done  by  the  earth- 
quake, another  element  must  be  considered,  namely,  the  fact  that 
only  hard  burned  terra-cotta  was  used  in  any  of  the  buildings 
in  that  city.  This  was  due  to  the  fact  that  a  suitable  hard-wood 
sawdust,  as  is  required  in  the  manufacture  of  porous  terra-cotta, 
was  not  available  in  that  locality.  Bearing  these  facts  in  mind, 
the  following  opinions  of  qualified  experts*  are  interesting  and 
valuable.  Mr.  Richard  L.  Humphrey  states: 

The  writer  is  of  the  opinion  that  the  present  commercial 
hollow  terra-cotta  tile  is  largely,  if  not  entirely,  devoid  of  merit 
for  fireproofing  purposes.  Even  when  it  is  of  the  best  grade  and 
workmanship  it  can  hardly  be  considered  a  first-class  building 
material.  At  a  comparatively  low  temperature  the  tiles  fail, 
the  thin,  webs  spalling  from  unequal  expansion.  A  more  porous 
tile,  with  thicker  webs  keyed  together  and  laid  in  Portland- 
cement  mortar  with  tight  joints,  would  unquestionably  be  more 
suitable  for  the  purpose.  It  may  be -true  that  in  case  of  repairs 
after  a  fire,  damaged  tile  of  the  usual  commercial  type  can  readily 
be  detected  and  renewed.  Terra-cotta  tiling  may,  however, 
allow  sufficient  heat  to  pass  through  it  to  soften  slightly  the  steel 
member  which  it  encases  and  still  remain  in  position,  thus  hiding 
the  defect.  Several  examples  of  this  condition  were  found. 

*  See  United  States  Geological  Survey  Bulletin  No.  324. 


MATERIALS   OF   FIRE-RESISTING    CONSTRUCTION      239 

Captain  Sewell  stated  as  follows: 

A  conflagration  never  yields  reliable  comparative  results, 
but,  judging  from  such  comparative  results  as  are  available,  I 
think  that  there  is  no  question  that  the  best  fire-resisting  ma- 
terial available  at  the  present  time  is  the  right  kind  of  burned 
clay  —  that  is,  a  good,  tough,  refractory  clay,  almost  as  refrac- 
tory as  fire-clay,  made  into  proper  shapes  and  properly  burned. 
Some  commercial  hollow-tile  work  is  made  of  good  material, 
but,  as  a  rule,  that  is  the  only  good  thing  that  can  be  said  about 
it.  There  can  be  no  question  that  good  clinker  concrete,  made 
of  well-burned  clinker,  Portland  cement,  and  sand,  is  a  very 
efficient  fire-resisting  material.  It  is  better  than  anything  except 
the  better  types  of  burned-clay  products;  but  the  cinder  concrete 
commercially  applied  is,  on  the  whole,  no  better  than  the  flimsy 
hollow-tile  work  with  which  it  competes,  in  fact,  it  is  not  cer- 
tain that  it  may  not  be  worse.  The  only  way  to  determine  this 
point  would  be  to  go  through  all  the  floor  construction  in  a  place 
like  San  Francisco  and  make  tests  of  the  load-carrying  capacity, 
etc.,  after  a  fire. 

Conclusions.  —  Considering  the  foregoing,  and  the  data 
given  in  Chapter  VI,  it  will  be  found  that,  on  the  one  hand, 
structural  terra-cotta  of  porous  or  semiporous  variety  has  been 
widely  commended,  and  deservedly  so,  for  its  endurance  and 
efficiency  where  intelligent  usage  and  adequacy  have  made  good 
results  possible.  On  the  other  hand,  it  has  been  found  wanting, 
and  condemned,  again  rightly,  for  its  faulty  behavior  where 
improper  material,  careless  use  or  flimsy  construction  obtained. 

Unfortunately,  in  the  great  majority  of  all  the  thousands  of 
cases  in  which  terra-cotta  has  been  used  for  the  protection  of 
steel  buildings,  the  full  importance  of  such  fireproofing  to  the 
life  or  fire-enduring  qualities  of  the  buildings  seems  to  be  largely 
disregarded  by  owners  and  architects  alike. 

Great  care  is  usually  bestowed  upon  the  design  of  the  steel 
frame,  possibly  by  the  architect,  or  possibly  by  an  associate  civil 
engineer.  Framing  plans  are  provided  for  the  steel  contractors 
to  estimate  upon,  usually  accompanied  by  ample  specifications. 
Likewise  the  masonry  walls  are  usually  of  ample  thickness, 
possibly  influenced  by  the  local  building  ordinance.  Why? 
Simply  because  these  portions  of  the  structural  design  cannot 
be  pared  down  without  danger  to  the  structure  under  everyday 
conditions. 

But  when  it  comes  to  the  terra-cotta  fireproofing,  no  material 
entering  largely  into  building  construction  has  been  so  trimmed 


240         FIRE   PREVENTION   AND   FIRE   PROTECTION 

down  to  insufficiency  or  ofttimes  used  with  so  little  intelligence. 
It  too  often  becomes  a  mere  veneer  of  pretense  —  the  use  of  a 
material  in  conventional  forms  simply  because  it  is  recognized 
as  standard.  Questions  of  adequacy,  stability,  proper  form  — 
in  short,  efficiency  in  all  ways  (as  is  further  pointed  out  in  Chap- 
ter X)  are  not  considered  necessary  of  investigation  or  explana- 
tion, simply  because  the  construction  is  of  the  usual  approved 
type. 

Every  contractor  of  fireproofing  material  will  recognize  the 
truth  of  these  statements.  Take,  for  example,  the  usual  data 
given  the  contractor  for  figuring  on  column  coverings.  It  is  to 
be  seriously  doubted  whether  one  set  of  building  plans  in  a 
hundred  gives  any  detailed  plan  of  the  shape,  thickness  or 
method  of  application  of  the  terra-cotta  blocks.  The  usual 
method  is  to  rely  upon  the  specification  requirements,  and  these 
are  usually  of  the  briefest.  As  an  instance,  fortunately  worse 
than  the  average,  consider  the  following,  extracted  verbatim 
from  the  specification  for  a  building  of  considerable  size  and  cost : 

11  Columns  and  Girder  Coverings.  —  All  columns  and  exposed 
girders  to  be  covered  with  terra-cotta,  to  conform  to  the  build- 
ing laws  and  to  make  a  good  surface  for  plastering." 

The  contractor,  therefore,  figures  on  no  better  work  than  his 
competitor,  and  even  such  work  which  protects  the  most  im- 
portant load-bearing  members  in  the  building  is  given  scant 
inspection  during  the  usual  hurried  building  operations.  Result, 
total  loss  to  the  column  protection,  as  was  shown  in  practically 
every  so-called  fire-resisting  building  which  passed  through  the 
Baltimore  fire.  It  is  this  lamentable  carelessness  in  detail,  care- 
lessness in  installation,  and  insufficiency  of  material  which  has 
resulted  in  terra-cotta,  the  material,  being  criticized  in  many 
quarters  for  the  faults  of  its  usage. 

But,  given  a  porous  or  semiporous  terra-cotta  to  start  with  — 
not  hard  burned,  brittle  material  —  of  adequate  thickness  and 
weight,  with  heavy  webs  and  partitions  to  all  blocks,  with  well- 
rounded  fillets  at  all  corners,  and  used  in  a  substantial  and  in- 
telligent manner,  and  no  better  fire-resisting  material  can  be 
used,  save  only  solid  brick  masonry. 

Concrete.  —  As  has  before  been  stated,  any  exhaustive  dis- 
cussion of  the  composition,  design,  use  or  fire-resisting  properties 
of  concrete  is  beyond  the  scope  of  this  handbook.  Attention 
will,  thereforet  be  limited  here  to  a  consideration  of  the  value 


MATERIALS    OF   FIRE-RESISTING    CONSTRUCTION      241 

of  concrete  construction  as  applied  to  fire-resisting  structures. 
Additional  data  concerning  concrete  will  be  found  in  Chapters 
VI,  VIII,  XII,  XIII,  XV,  XVII  to  XXI  inclusive,  and  XXIII 
to  XXVI  inclusive. 

The  suitability  of  concrete  for  use  in  buildings  intended  to  be 
fire-resistive  will  largely  depend  upon  its  composition,  its  form 
or  design,  its  use  or  method  of  placing,  its  fire-resisting  proper- 
ties, its  thermal  conductivity  and  its  influence  upon  the  life 
of  iron  or  steel  embedded  therein. 

Composition  of  Concrete.  —  Concrete  is  a  mixture  of 
cement,  sand  and  some  coarser  or  more  bulky  aggregate.  In- 
asmuch as  a  more  or  less  uniform  grade  of  sand  and  some  recog- 
nized standard  brand  of  Portland  cement  are  now  common  to 
nearly  all  concrete  mixtures,  the  differences,  if  any,  in  the  fire- 
resisting  properties  of  concretes  should  be  found  in  the  charac- 
ter of  the  aggregate  employed.  Numerous  tests  show  that  this 
is  so. 

Aggregates  used  in  concrete  include 

Natural  materials,  such  as  crushed  or  broken  stone,  gravel 
and  volcanic  rocks  (basalts,  traps,  lavas  and  pumice,  etc.)  and 
artificial  materials,  such  as  blast-furnace  slag,  cinders,  broken 
brick  and  broken  terra-cotta. 

In  English  practice,  gravel  is  generally  termed  "  Thames 
ballast"  or  " natural  ballast,"  presumably  from  the  use  of 
ballast  gravel  taken  from  the  banks  of  the  Thames.  Also 
English  practice  does  not  countenance  the  use  of  cinders,  but 
"coke  breeze"  or  crushed  coke,  " clinker"  or  furnace  slag,  and 
blast-furnace  slag  are  frequently  employed. 

Design  and  Use  of  Concrete  Construction.  —  In  the  em- 
ployment of  concrete,  proper  design  and  intelligent  usage  are 
of  even  more  importance  than  the  fire-resisting  qualities  of  the 
material.  With  terra-cotta  tile,  careless  use  or  workmanship 
may  endanger  the  protection  of  the  steel  frame  in  time  of  fire 
test.  With  concrete,  improper  design  or  careless  workmanship 
may  endanger  the  very  safety  of  the  entire  structure.  "The 
man  with  the  hoe,"  i.e.,  the  unskilled  laborer,  frequently  em- 
ployed on  this  class  of  work,  contributes,  unless  given  very  close 
supervision,  a  considerable  element  of  uncertainty  to  the  finished 
product.  The  questions  of  design  and  workmanship  of  concrete 
and  reinforced-concrete  floors,  etc.,  are  considered  in  more  detail 
in  Chapter  XVIII. 


242         FIRE   PREVENTION   AND   FIRE   PROTECTION 

Fire-resisting  Qualities  of  Concrete.  —  Probably  few 
subjects  connected  with  fire-resisting  construction  have  been 
more  widely  discussed  during  the  past  several  years  than  has 
the  ability  of  concrete  to  withstand  test  by  fire.  The  greatly 
increased  use  of  concrete,  not  only  for  floor  constructions  and 
column  protections,  but  for  entire  buildings  as  well,  in  the  form 
of  reinforced  concrete,  makes  this  question  of  vital  interest. 
Several  chapters  could  easily  be  filled  without  even  then  approach- 
ing an  exhaustive  discussion,  but,  as  in  the  case  of  structural 
terra-cotta,  attention  will  here  be  confined  to  a  brief  description 
of  some  of  the  more  important  tests  which  have  been  made, 
and  to  the  opinions  of  some  prominent  investigators. 

German  Fire  Tests  of  Concrete.  —  Some  of  the  most  com- 
plete experiments  ever  made  to  determine  the  fire-resisting 
qualities  of  different  mixtures  of  concrete  were  conducted  by  a 
commission  appointed  by  the  city  of  Hamburg,  Germany. 
These  tests  were  made  some  years  ago,  and  quite  an  elaborate 
report  of  the  investigations  was  issued  in  1895.* 

Tests  were  made  on  sixteen  varieties  of  concrete  mixtures. 
These  included  cement  and  sand;  cement  and  gravel;  cement, 
sand  and  broken  stone;  cement  and  fine  cinders;  cement  and 
coarse  cinders;  and  cement,  sand  and  broken  basalt.  The 
tests  consisted  of  exposing  the  samples  to  fire  at  a  temperature 
of  1080°  C.  or  1976°  F.  for  a  period  of  several  hours  (3f  hours  in 
some  cases),  and  then  either  cooling  slowly  or  very  suddenly 
by  the  application  of  cold  water. 

The  report  shows  that  while  all  of  the  sand,  gravel  and 
stone  mixtures,  with  one  exception,  either  crumbled  or  showed 
greatly  reduced  coherence  after  the  test,  the  cinder  concretes, 
especially  the  coarse  mixture,  gave  most  excellent  results.  The 
latter  "showed  good  coherence"  and  "did  not  suffer"  by  wetting 
while  hot.  In  this  respect  the  endurance  of  these  concretes  ex- 
ceeded that  of  bricks  laid  in  cement  mortar,  as  the  report  states 
that  "some  bricks  cracked,"  and  the  mortar  became  "very 
tender  and  lost  its  binding  power." 

The  highest  degree  of  coherence  in  the  concretes,  particu- 
larly in  the  center  of  the  mass  tested,  was  shown  by  a  mixture 
of  1  part  cement  to  7  parts  of  coarse  cinders.  Fire  was  applied 
3f  hours.  One  sample  was  cooled  suddenly,  and  one  slowly, 
but  neither  suffered  under  the  test. 

Professor  Bauschinger  of  the  Munich  Technical  School  made 
tests  of  concrete  pillars  by  heating  and  quenching.  In  his 

*  For  general  results  of  report  see  "The  Materials  of  Construction,"  by 
J.  B.  Johnson. 


MATERIALS    OF   FIRE-RESISTING    CONSTRUCTION       243 

report  of  these  experiments  he  stated  that  "of  all  the  materials 
tested,  Portland-cement  concrete  stood  the  best,  and  ordinary 
and  clinker  bricks  laid  in  Portland-cement  mortar  stood  almost 
equally  as  well." 

New  York  Building  Department's  Tests  of  Concrete.— 
One  of  the  fire  tests  of  concrete  floors,  made  by  the  New  York 
Building  Department,  is  described  in  .detail  in  Chapter  XVIII. 
These  tests  also  bear  out  the  Hamburg  experiments  in  pointing 
to  cinder  concrete  as  the  most  desirable  mixture  from  a  fire- 
resisting  standpoint;  but  even  in  the  Columbian  floor  test, 
where  a  broken-stone  concrete  was  used,  without  the  added 
protection  of  a  suspended  ceiling,  the  test  was  very  satisfactory 
from  a  general  standpoint. 

Mr.  Rudolph  P.  Miller,  Superintendent  of  Buildings  in  New 
York  City,  thus  summarizes  these  tests:* 

The  conclusion,  from  a  study  of  the  tests  in  detail,  shows 
that,  to  a  depth  averaging  about  one  inch,  the  concrete  is  seri- 
ously impaired  and  is  easily  washed  off  by  a  hose  stream  applied 
to  the  surface.  Any  stone  containing  an  appreciable  percentage 
of  carbonate  of  lime  will  calcine  and  cause  failure.  Where  the 
construction  is  poorly  designed,  allowing  an  excessive  deflection, 
the  fine  cracks  in  the  concrete  below  the  steel  will  open  to  such 
an  extent  as  to  allow  the  heat  to  reach  the  metal  reinforcements. 
When  the  reinforcement  is  such  as  to  produce  a  plane  of  weakness 
in  the  concrete,  there  is  liable  to  be  a  flaking  off  of  concrete  and 
a  consequent  exposure  of  metal. 

British  Fire  Prevention  Committee's  Tests  of  Concrete. 

—  It  is  safe  to  say  that  the  fire-tests  of  the  British  Fire  Preven- 
tion Committee  are  made  with  such  fairness  and  accuracy  that 
they  are  worthy  of  being  considered  conclusive,  not  only  in 
England,  but  in  this  country  as  well.  Touching  on  the  fire 
resistance  of  concrete,  "Red  Books"  Nos.  101,  106,  107  and  108 
are,  therefore,  of  great  interest  and  value  in  the  determination 
of  the  effects  of  aggregates  upon  the  fire-resisting  properties  of 
various  concrete  mixtures.  As  the  tests  described  in  the  above- 
enumerated41  Red  Books  "  were  all  of  floor  constructions,  details 
of  same  are  given  in  Chapter  XVIII,  but  the  conclusions  given 
as  results  of  the  tests,  were  briefly  as  follows : 

No.  101.  —  The  test  did  not  go  far  enough  to  draw  definite 
conclusions  except  to  show  the  entire  unreliability  of  Thames 
ballast  (gravel)  concrete  as  a  suitable  material. 

*  See  Kidder's  "Architects'  and  Builders'  Pocket-Book,"  p.  881  y.  1909 
Edition. 


244         FIRE   PREVENTION    AND    FIRE    PROTECTION 

No.  106.  —  This  test  demonstrates  that  reinforced  con- 
crete, made  with  clinker  (furnace  slag)  as  an  aggregate,  may  be 
classed  as  a  fire-resisting  material,  but  it  also  demonstrates  that 
additional  protection  to  that  provided  in  this  test  (about  one 
inch)  is  required  for  the  steel  reinforcement. 

No.  107.  —  This  test  demonstrates  the  unreliability  of 
ordinary  gravel  or  Thames  ballast  concrete  as  a  fire-resisting 
material  at  high  temperatures. 

No.  108.  —  It  is  interesting  and  instructive  to  compare 
this  test  with  the  former.  The  floors  were  practically  identical 
so  far  as  their  construction  was  concerned,  the  only  difference 
being  the  aggregate  of  which  the  concrete  of  the  bays  and  sup- 
porting beams  was  composed.  The  test  clearly  demonstrates 
the  superiority  of  clinker  (furnace  slag)  and  coke-breeze  concrete 
over  Thames  ballast  (gravel) . 

United  States  Geological  Survey  Tests  of  Concrete.  —  It 

is  much  to  be  regretted  that  the  tests  made  by  the  United  States 
Geological  Survey  at  the  Underwriters'  Laboratories  did  not 
comprise  a  greater  variety  of  aggregates,  and,  also,  that  only  two 
tests  were  made  of  cinder  concrete,  and  those  of  the  poorest  qual- 
ity of  soft-coal  cinders  containing  24.5  per  cent,  of  combustible 
matter.  Additional  tests  may  remedy  these  defects,  and  the 
consequent  inconclusiveness  of  the  results.  After  the  British 
tests  described  above,  the  desirability  of  testing  all  possible 
aggregates  is  apparent,  and  further  tests  should  certainly  include 
concretes  made  of  a  good  quality  of  cinders,  crushed  brick, 
broken  terra-cotta  and  blast-furnace  slag. 

A  summary  of  the  United  States  Geological  Survey  tests  is 
thus  given  in  Bulletin  No.  370: 

It  was  difficult  to  determine  whether  the  limestone,  granite, 
gravel  or  cinder  concrete  sustained  the  least  damage.  The 
faces  of  all  the  panels  were  more  or  less  pitted  by  the  fire  and 
washed  away  by  the  stream  of  water.  The  test  was  unfair  to 
the  cinder  concrete,  as  the  cinder  was  very  poor,  containing  a 
large  percentage  of  unburned  coal ;  however,  the  sample  selected 
was  the  best  of  six  or  eight  investigated  in  St.  Louis.  During 
the  fire  test  the  coal  ignited  and  left  the  surface  of  the  concrete 
very  rough  and  badly  pitted.  The  limestone  aggregate  in  the 
face  calcined,  and  the  granite  aggregate  split  and  broke  away 
from  the  surface  mortar.  The  granite  concrete  probably  be- 
haved the  best.  The  damage  in  no  case  extended  deeply, 
probably  not  more  than  1|  inches.  The  evidence  shows  that 
even  at  this  depth  the  temperature  was  comparatively  low. 
The  high  stresses  produced  in  the  panels  by  the  rapid  rise  of 
temperature  of  the  faces  while  the  backs  remained  cool  caused 


MATERIALS   OF   FIRE-RESISTING    CONSTRUCTION      245 

cracks.  On  taking  down  the  panels,  the  blocks  of  concrete  were 
found  to  be  cracked  vertically  for  some  distance  back  from  the 
face. 

Concrete  in  Baltimore  Fire.  —  See  Chapter  VI,  page  176. 

Concrete  in  San  Francisco  Fire.  —  Turning,  now,  to  tests 
of  concrete  constructions  in  actual  fires,  a  wide  divergence  of 
opinion  will  be  found,  even  among  those  qualified  by  experience 
and  careful  observation  to  pass  judgment.  It  is  generally  ad- 
mitted that  the  Baltimore  fire  did  not  offer  any  conclusive 
evidence  regarding  concrete,  but  in  San  Francisco  many  concrete 
constructions  suffered  tests,  and  the  following  extracts  from 
United  States  Geological  Survey  Bulletin  No.  324  will  indicate 
the  prevalence  of  conflicting  testimony. 

Prof.  Frank  Soule  summarized  the  action  of  concrete  as  follows : 

There  are  two  opposing  parties  in  the  matter  of  fireproofing 
in  San  Francisco  —  those  who  have  favored  the  hollow-tile 
system,  and  those  who  believe  in  concrete  as  the  best  fireproofing 
material.  .  .  .  Good  Portland-cement  concrete  has  won  a 
triumph  for  itself  in  fireproofing  in  San  Francisco,  for  wherever 
well  made  and  properly  laid  upon  the  steel  girders  or  columns, 
it  protected  the  metal.  In  very  hot  fires  the  exterior  portions 
were  disintegrated,  and  in  some  places  the  whole  mass  was 
cracked,  necessitating  removal,  but  the  fireproofing  it  furnished 
was  excellent.  Examination  showed  also  that  it  protected  well 
against  rust.  The  heat  to  which  it  was  subjected  was  very 
great ;  in  places  common  mortar  was  fused  and  ironwork  in 
walls  melted.  .  .  .  The  weight  of  Portland-cement  concrete  is 
a  drawback,  and,  moreover,  concrete  is  expensive  when  well 
made  and  applied.  Cinder  concrete  was  well  esteemed  for 
fireproofing  for  floors,  but  the  scarcity  of  good  cinders  in  the  city 
rendered  its  general  employment  impracticable. 

Conclusions,  concerning  the  fire-resisting  properties  of  struc- 
tural materials,  by  Mr.  Richard  L.  Humphrey  contain  the  fol- 
lowing reference  to  concrete: 

The  advocates  of  terra-cotta  tile  contend  that  concrete 
may  be  seriously  damaged  by  dehydration  without  noticeable 
change  in  its  appearance.  While  this  contention  may  be  justi- 
fied, it  should  be  noted  that  any  weakness  or  softness  may  be 
as  readily  detected  and  repaired  in  concrete  as  in  terra-cotta. 
Concrete,  moreover,  has  the  great  advantage  of  being  a  non- 
conductor of  heat,  and  so  will  withstand  a  prolonged  heat  before 
the  damage  extends  to  any  great  depth ;  and  it  usually  remains 
in  place,  maintaining  its  protective  qualities.  The  value  of  a 
structure  or  of  a  method  of  fireproofing  is  determined  largely 
by  ascertaining  what  portion  of  the  structure  is  left  available 


246         FIRE   PREVENTION   AND   FIRE   PROTECTION 

for  use  after  the  fire.  The  word  "fireproof"  is  of  course  a  mis- 
nomer, for  no  building  is  absolutely  fireproof;  and  the  resistance 
offered  to  fire  is  one  of  degree  only,  for  if  the  heat  be  sufficiently 
high  and  prolonged,  nothing  can  withstand  it.  The  best  ma- 
terials are  non-conductors  of  heat,  having  high  fusing  points. 
At  high  temperature  concrete  loses  its  water  of  crystallization, 
but  the  depth  to  which  this  dehydration  goes  and  the  rate  at 
which  it  takes  place  are  the  factors  that  determine  the  effective- 
ness of  the  material.  The  heat  insulation  afforded  by  concrete 
is  of  a  high  order,  and  to  obtain  the  best  results  a  sufficient 
thickness  must  be  applied.  This  required  thickness  is  naturally 
a  variable  quantity;  2  inches,  or  even  1  inch,  may  be  sufficient 
for  an  office  building,  but  would  be  inadequate  for  a  warehouse. 
These  remarks  concerning  concrete  also  apply  to  all  other  forms 
of  fireproofing.  The  prime  point  on  which  information  should 
be  procured  is  the  thickness  of  the  insulation  for  proper  pro- 
tection against  fire. 

The  above-quoted  opinions,  given  only  after  most  careful  and 
extensive  examination  into  the  conditions  of  buildings  which 
passed  through  the  San  Francisco  conflagration,  are  distinctly 
favorable  to  concrete.  It  should  be  noticed,  however,  that  both 
opinions  lay  more  stress  on  the  fireproofing  qualities  of  concrete 
in  protecting  metal  members  or  reinforcement  than  upon  the 
integrity  of  the  entire  construction,  that  is,  its  load-bearing 
ability,  after  test  by  fire.  Hence  it  is  not  surprising  that 
others,  judging  the  behavior  of  concrete  more  from  the  latter 
standpoint,  are  less  eulogistic  in  their  conclusions.  Thus 
Captain  Sewell  points  out*  that 

If  a  hollow-tile  floor,  for  instance,  loses  its  lower  webs,  the 
damage  is  very  apparent,  yet  most  of  such  floors  remain  true 
and  capable  of  carrying  considerable  loads.  A  cinder-concrete 
floor  which  is  even  more  seriously  damaged  is  very  likely  to 
remain  true,  for  the  reason  that  the  fire  which  damaged  it  also 
removed  its  superimposed  load  before  the  damage  was  fully 
accomplished.  A  hollow  tile  which  comes  through  a  fire  without 
losing  any  of  its  webs  is  as  good  as  it  was  before;  whereas  con- 
crete of  any  kind  which  has  come  through  a  fire  in  which  the 
temperature  has  exceeded  700°  or  800°  F.  is  inevitably  damaged 
in  all  cases,  owing  to  the  dehydration  of  the  cement,  although 
it  may  appear  uninjured  to  the  casual  observer.  This  property 
of  concrete,  of  maintaining  a  good  face  in  spite  of  real  and  serious 
damage,  is  likely  to  lead  the  layman  into  dangerous  conclusions, 
and  consequently  into  equally  dangerous  practice.  It  would 
seem  that  wherever  reinforced-concrete  floor  construction  is 
used,  a  furred  ceiling  below  it  should  be  absolutely  required. 

*  Bulletin  No.  324,  p.   120. 


MATERIALS    OF    FIRE-RESISTING    CONSTRUCTION      247 

The  report  of  the  committee  of  members  of  the  American 
Society  of  Civil  Engineers,  on  "Fire  and  Earthquake  Damage  to 
Buildings,"*  found  that,  where  unprotected,  concrete  was  in 
most  cases  destroyed.  "The  concrete  is  dry,  and  while  in  many 
cases  hard,  yet  all  the  water  has  been  burned  out  and  it  may 
be  said  to  be  destroyed,  even  if  able  to  support  weights."  Where 
concrete  floors  had  hung  ceilings,  they  reported  the  concrete 
generally  uninjured. 

For  more  detailed  accounts  of  concrete  constructions,  etc., 
in  the  San  Francisco  fire,  see  United  States  Geological  Bulletin 
No.  324,  Transactions  Am.  Soc.  C.  E.,  Vol.  LIX,  and  volume 
"San  Francisco  Earthquake  and  Fire,"  by  A.  L.  A.  Himmel- 
wright,  C.  E.,  published  by  the  Roebling  Construction  Company. 

Thermal  Conductivity  of  Concrete.  —  A  large  number  of 
tests  of  the  thermal  conductivity  of  concrete  and  steel  embedded 
therein  (also  tests  regarding  the  effect  of  heat  upon  strength  and 
elastic  properties)  has  been  made  by  Prof.  Ira  H.  Woolson. 
These  tests  demonstrated  that  concrete  has  a  very  low  thermal 
conductivity,  and  the  use  of  different  aggregates,  whether  lime- 
stone, trap  rock,  gravel  or  cinders,  did  not  seem  to  have  any 
material  effect  upon  the  result.  Well-made  cinder  concrete 
showed  the  lowest  conductivity.  It  was  found  that  concrete 
of  a  one  to  four  mixture,  properly  dried  for  a  month  or  six  weeks, 
would  maintain  a  heat  of  1600°  to  1800°  F.  on  its  face,  while 
two  inches  below  the  face  the  temperature  would  not  rise  to 
500  degrees  in  four  or  five  hours. f 

As  the  result  of  his  experiments,  Professor  Woolson  gives  the 
following  general  conclusions. t 

(1)  That  all  concrete  mixtures  when  heated  throughout  to 
a  temperature  of  1000°  to  1500°  F.  will  lose  a  large  proportion  of 
their  strength  and  elasticity,  and  this  fact  must  be  well  remem- 
bered in  designing. 

(2)  That  all  concretes  have  a  very  low  thermal  conductivity 
and  therein  lies  their  well-known  heat-resisting  properties. 

(3)  That  as  a  result  of  this  low  thermal  conductivity,  two 
to  two  and  a  half  inches  of  concrete  covering  will  protect  rein- 
forcing metal  from  injurious  heat  for  the  period  of  any  ordinary 
conflagration  (provided,  of  course,  that  the  concrete  stays  in 
place  during  the  fire). 

*  See  Transactions,  Am.  Soc.  C.  E.t  Vol.  LIX,  p.  239. 

t  See  1909  Proceedings  National  Fire  Protection  Association,  p.  166. 

$  See  Engineering  News,  August  15,  1907. 


248         FIRE   PREVENTION    AND   FIRE   PROTECTION 

(4)  That  reinforcing  metal  exposed  to  the  fire  will  not  convey 
by  conductivity  an  injurious  amount  of  heat  to  the  embedded) 
portion. 

(5)  That  the  gravel  concrete  was  not  a  reliable  or  safe  fire- 
resisting  aggregate. 

The  United  States  Geological  Survey  tests  (see  Bulletin  No. 
370)  also  emphasized  the  low  heat-transmission  properties  of 
Portland  cement,  mortars  and  concretes.  For  marking  the 
cement  blocks,  linen  tags  were  fastened  by  means  of  wire  nails 
to  the  interior  walls  of  the  blocks  at  the  time  of  moulding. 
Most  of  these  tags  remained  in  place,  and  all  were  found  un- 
injured after  the  fire  tests. 

Loss  of  Strength  of  Concrete  under  Fire  Test.  —  That 
the  criticisms  of  Captain  Sewell,  and  of  the  Committee  of  the 
American  Society  of  Civil  Engineers,  regarding  the  loss  of 
strength  of  concrete  after  fire  test,  are  well  founded,  is  shown 
pretty  conclusively  by  the  strength  tests  made  by  Professor 
Woolson,  above  referred  to.  Summaries  of  the  results  deter- 
mined from  those  experiments  are  given  in  the  following  table.* 


CRUSHING   STRENGTH  OF  CONCRETE,   HEATED  ON  ALL 
SIDES,  BEFORE  AND  AFTER  HEATING. 


Lot  material. 

Breaking'  loads,  pounds  per  square  inch. 

Not 
heated. 

Same 
lot  in 
1905 
when  1 
mo.  old 

After 
heating 
2  hrs.  at 
1500°  F. 

After 
heating 
3  hrs.  at 
1500°  F. 

After  heating 
5  hours  at 
1500°  F. 

4X4X4  inch  specimens. 


A  Limestone. 
B  Trap  rock. 
C  Cinder.... 
D  Gravel.... 
E  Limestone 
old.. 


1  year 


F  Trap  rock  1  year  old 


K  6-inch    cube    lime- 
stone 2  years  old 


3030 

980 

1445 

3195 

1300 

1410 

1360 

750 

447 

2740 

1741 

1968 

1235 

937 

2165 

1843 

1110 

906 

1640 

1200 

1290 

2230 

1903 

1525 

665 

2800 

1913 

695 

2240 

1892 

4  hrs. 

2290 

2005 

Engineering  News,  June  28,  1906. 


MATERIALS    OF   FIRE-RESISTING    CONSTRUCTION      249 


CRUSHING  STRENGTH  OF  CONCRETE,  HEATED  ON  ALL 
SIDES,  BEFORE  AND  AFTER  HEATING  (continued). 

6  X  6  X  14  inch  specimens. 


A 

2740 

1345 

870 

1840* 

B  

3140 

1400 

997 

1705* 

C  . 

1400 

547 

504 

D  

2780 

NOTE.  — Where  more  than  one  breaking  load  is  given  it  indicates  that  several 
specimens  were  tested. 

*  Heated  on  one  side  only. 

Fireprooflng  of  Concrete.  —  A  logical  deduction  from  the 
preceding  considerations  is  that  all  important  load-bearing 
members  of  concrete  or  reinforced  concrete,  whether  floors, 
beams,  girders,  columns  or  walls,  require  protective  coverings 
which  shall  serve  as  insulators  only,  and  which  can  suffer  partial 
or  complete  damage  without  affecting  the  essential  load-bearing 
parts.  Such  protective  coverings  may  take  the  form  of  an 
added  thickness  of  concrete  (whether  of  the  same  composition 
as  the  rest  of  the  construction  or  of  a  special  fire-resisting  mix- 
ture), or  entirely  different  materials  may  be  employed. 

In  either  case  the  amount  of  protection  required  is  dependent 
upon  the  character  of  the  building  and  the  amount  of  combus- 
tible contents.  Manifestly  a  building  with  small  units  of  area, 
incombustible  floors  and  trim,  containing  a  limited  quantity 
of  combustible  furnishings,  would  not  require  as  much  protection 
for  its  structural  parts  as  a  building  of  large  areas  and  hazardous 
contents.  Thus  no  hard  and  fast  rules  may  be  laid  down. 

If  the  protection  is  to  be  afforded  by  an  added  thickness  of 
the  concrete  itself,  cinder-concrete  covering  would  seem  the 
most  applicable  on  account  of  its  superior  fire-resisting  qualities, 
and  from  the  opinions  and  experiments  previously  quoted,  some 
more  or  less  general  rules  as  to  the  thickness  required  may  be 
deduced.  Thus  Mr.  Humphrey  advises  1  inch  to  2  inches  or 
more,  depending  on  the  exposure;  the  St.  Louis  tests  showed 
no  damage  to  a  depth  greater  than  H  inches;  while  Professor 
Woolson,  from  his  extensive  experiments,  advises  from  2  to 

inches.  The  Building  Code  recommended  by  the  National 
Board  of  Fire  Underwriters  calls  for  "all  columns  and  girders 

reinforced  concrete  to  have  at  least  one  inch  of  material  on 
ill  exposed  surfaces  over  and  above  that  required  for  structural 


250         FIRE   PREVENTION   AND   FIRE   PROTECTION 

purposes,  and  all  beams  and  floor  slabs  to  have  at  least  three- 
quarters  inch  of  such  surplus  material  for  fire-resisting  purposes. " 
Messrs.  Taylor  and  Thompson,  in  their  "  Treatise  on  Con- 
crete," state  as  follows: 

Observations  of  steel  embedded  in  concrete  which  has  been 
exposed  to  fire  or  to  corrosive  action,  and  experimental  tests 
prove  conclusively  that  1J  to  2  inches  of  dense  Portland-cement 
concrete,  made  in  ordinary  proportions,  with  broken  stone, 
gravel  or  cinders,  of  good  quality,  and  mixed  wet,  will  effectually 
resist  the  most  severe  fire  liable  to  occur  in  buildings,  and  will 
prevent  the  corrosion  of  steel  even  under  extraordinary  condi- 
tions. In  members  of  inferior  importance  or  which  are  only 
liable  to  fire  of  comparatively  low  temperature,  a  less  thickness 
of  concrete,  in  many  cases  f  inch  or  even  \  inch,  will  prove 
effective. 

A  fair  average  working  rule  would  seem  to  be  about  as  fol- 
lows: For  columns,  trusses,  girders  or  other  very  important 
structural  members,  at  least  2  inches  of  concrete  outside  of  all 
metal  reinforcement;  for  ordinary  beams,  or  for  long-span  floor 
arches,  at  least  \\  inches  of  concrete  outside  of  the  reinforce- 
ment; and  for  short-span  floor  arches,  partitions,  walls,  etc., 
at  least  1  inch. 

As  such  protective  coverings  are  added  in  the  expectation 
that  they  will  be  completely  or  partially  destroyed  under  fire 
test,  and  also  as  cinder  concrete  especially  is  incapable  of  carry- 
ing any  great  loads,  this  excess  material  should  not  be  included 
in  the  estimated  effective  load-bearing  section. 

If  cinder  concrete  coverings  are  used  (around  columns,  girders 
and  beams,  and  on  the  under  surface  of  floor  slabs),  great  care 
will  be  necessary  in  the  employment  of  the  two  mixtures  of 
concrete  so  that  only  the  proper  amount  of  the  weaker  mixture 
be  used,  and  that  it  be  placed  in  the  proper  position  immedi- 
ately before  or  after  the  structural  concrete,  in  order  that  a 
bond  between  the  two  may  be  secured.  A  practical  method  of 
using  cinder  concrete  as  a  protective  covering  for  reinforced- 
concrete  columns  is  described  in  Chapter  XII.  Floor-arch 
protections  are  discussed  in  Chapter  XVIII. 

If  the  protection  is  to  be  afforded  by  materials  other  than 
concrete,  lath  and  plaster,  hollow  brick  or  structural  terra-cotta 
may  be  used.  In  Chapter  XII  the  National  Fire  Proofing  Com- 
pany's system  of  combination  concrete  and  terra-cotta  columns 
is  described. 


MATERIALS    OF    FIRE-RESISTING    CONSTRUCTION      251 

The  corrosive  actions  of  different  mixtures  of  concrete  are 
discussed  in  Chapter  VIII. 

Conclusions  regarding  Concrete.*  —  From  the  foregoing 
discussion  of  concrete,  as  applied  to  fire-resisting  construction, 
it  is  seen  that  the  most  important  factors  concern  the  questions 
of  aggregates,  the  disintegration  which  must  be  expected,  and 
the  amount  of  added  protection  necessary  to  cover  such  damage. 
The  latter  two  essentials  have  been  sufficiently  considered,  but 
the  question  of  aggregates  is  worthy  of  more  attention. 

The  best  aggregate  to  be  had  in  any  particular  locality  for  a 
concrete  which  shall  be  both  strong  and  fire-resisting  is  difficult 
to  determine.  Such  an  aggregate  must  be  generally  available 
and  also  cheap. 

Stone,  whether  granite,  sandstone,  limestone  or  trap,  contains 
moisture,  and  hence  is  subject  to  dehydration.  When  used  as 
an  aggregate,  stone  breaks  or  disintegrates  under  high  heat  and 
the  bond  between  the  aggregate  and  the  cement  is  also  broken. 

Artificial  aggregates,  such  as  coke  breeze  and  cinders,  contain 
no  water  of  crystallization,  but  they  are  neither  strong  enough 
nor  available  enough  to  warrant  their  extended  use. 

Coke  breeze  has  been  shown  by  the  British  Fire  Prevention 
Committee  tests  to  be  a  most  excellent  aggregate,  but  as  far  as 
the  writer  knows,  it  has  never  been  employed  in  this  country. 

Cinder  concrete  may  be  made  of  a  good,  bad  or  indifferent 
grade  of  cinders,  and  it  is  to  be  feared  that  the  cinders  ordinarily 
employed  in  such  constructions  are  generally  bad,  sometimes 
indifferent,  very  seldom  good. 

Cinders,  as  bought  and  used  by  most  fireproofing  companies, 
are  usually  nothing  more  than  ashes  obtained  from  the  burning 
of  " slack,"  or  the  screenings  obtained  from  large  soft  coal. 
This  fuel  is  ordinarily  used  in  the  large  power  plants,  factories, 
or  sugar  refineries  from  which  the  cinders  are  generally  bought. 
Such  cinders  are  always  sold  unscreened,  and  they  are  usually  a 
very  poor  product  —  too  poor  for  use  in  anything  better  than  a 
cinder  concrete  filling  over  the  arches  proper,  and  even  for  filling, 
a  better  grade  of  concrete  is  desirable. 

A  really  good  cinder  can  be  obtained  from  hard  coal  only, 

but  if  this  cannot  be  had,  lump  soft  coal  is  far  preferable  to  the 

"  slack"  or  coal  screenings.     Cinders  should  always  be  screened 

through  a  2-inch  mesh,  but  this  is  seldom  done  in  practice. 

*  See  also  "Conclusions,"  Chapter  XVIII,  p.  620. 


252         FIRE   PREVENTION    AND    FIRE    PROTECTION 

The  previous  description  of  the  United  States  Geological 
Survey  tests  on  concrete  shows  the  difficulty  of  obtaining  a 
suitable  grade  of  cinders.  The  best  of  six  or  eight  samples 
obtainable  in  St.  Louis  contained  24.5  per  cent,  of  combustible 
matter. 

Also  cinder  concrete  is  out  of  the  question  where  strength  is 
concerned,  and  its  corrosive  tendencies  are,  to  say  the  least, 
undetermined. 

Broken  brick  and  broken  terra-cotta  tile  would  be  admirable 
aggregates  if  available,  but  they  are  neither  plenty  nor  cheap, 
at  least  in  all  localities. 

Blast-furnace  slag,  in  the  author's  opinion,  offers  the  best 
solution  for  an  aggregate  which  shall  satisfy  requirements  as 
to  both  strength  and  fire  resistance.  See  "Load  Tests  of 
Blast-furnace  Slag  Concretes,"  and  "Conclusions,"  pages  619 
and  620. 

Concrete  vs.  Terra-cotta:  Conclusion.  —  The  writer  be- 
lieves that  there  is  no  decided  choice  between  good  concrete  and 
good  structural  terra-cotta  constructions.  Good  concrete  work 
is  decidedly  preferable  to  poor  terra-cotta  work,  and  conversely, 
good  terra-cotta  construction  is  undoubtedly  better  than  poor 
concrete. 

The  conclusion  of  Captain  Sewell  on  this  point  is  worth  much 
emphasis:  "The  results  at  Baltimore  and  San  Francisco  did  not, 
by  any  means,  indicate  that  either  hollow  tile  or  concrete  is 
altogether  a  failure  or  altogether  a  success.  Both  fires  indicated 
very  clearly  that  commercial  methods  of  applying  both  ma- 
terials are  inadequate,  but  also  that  successful  results  can  be 
attained  with  both  materials."* 

Concrete-  and  Mortar-blocks.  —  The  manufacture  of  con- 
crete- or  mortar-blocks  varies  considerably,  according  to  the 
materials  used  and  the  process  of  manufacture  followed.  The 
many  plants  now  making  these  cement  blocks  use  a  wide  range 
of  materials,  usually  selecting  the  best  obtainable  locally  at 
a  reasonable  cost.  If  the  mixture  used  consists  of  cement  and 
sand  only,  the  blocks  are  generally  termed  "mortar-blocks"  or 
"concrete  building  tile."  If  cement,  sand  and  some  aggregate 
are  used,  the  blocks  are  called  "concrete-blocks."  Aggregates 
in  common  use  include  gravel,  screenings  of  trap  rock  and  lime- 
stone, and  granulated  slag. 

*  United  States  Geological  Bulletin  No.  324,  p.  120. 


MATERIALS   OF   FIRE-RESISTING    CONSTRUCTION      253 

Process  of  Manufacture.  —  Several  distinct  processes  of  manu- 
facture are  followed,  according  to  the  type  of  machine  and  the 
mixture  of  materials  used.  These  may  be  divided  into  two 
general  classes  — viz.,  the  "dry"  process  and  the  "wet"  process. 
In  the  "dry"  process,  the  mixture  employed  is  comparatively 
dry  when  tamped  into  moulds.  The  "wet"  process,  generally 
considered  preferable,  may  be  briefly  described  as  follows: 

A  mixture  of  1  :  4  is  prepared  in  a  batch  mixer  so  it  will 
flow  like  cream.  From  the  mixer  the  material  is  run  into  a 
circular  trough  over  the  machines,  in  which  what  is  termed  an 
agitator  keeps  the  mix  in  continuous  motion,  thereby  maintain- 
ing the  proper  consistency  and  preventing  setting-up  until  it  is 
drawn  out  of  the  agitating  troughs  into  the  machines  below. 
These  machines  can  be  constructed  to  manufacture  any  size  of 
block  that  might  be  specified,  provided  the  web  is  of  equal 
thickness  throughout.  The  machines  are  steam  heated,  some- 
thing on  the  order  of  a  steam  radiator,  both  the  outer  and  inner 
walls  being  hollow.  The  moulds  are  filled  with  the  liquid  con- 
crete from  the  agitator  as  stated  above,  and  if  the  cement  is 
reasonably  quick  setting  (say  takes  its  initial  set  in  1  hour  or 
1  hour  and  20  minutes)  the  blocks  can  be  removed  in  from  5  to 
10  minutes  according  to  the  thickness  of  the  web.  The  steam- 
heated  moulds  drive  off  the  surplus  moisture  in  vapor,  thereby 
hastening  the  set  of  the  blocks  which  are  then  simply  pushed 
out  of  the  machine,  thoroughly  saturated  with  a  fine  spray  of 
water,  and  put  into  the  steam  room  where  they  remain  for  from 
24  hours  to  6  days.  The  blocks  are  removed  from  the  steam 
room  in  about  24  hours  to  let  nature  complete  the  curing  pro- 
cess. If  hurry  exists  for  any  special  sizes,  the  blocks  can  be 
left  in  the  steam  room  for  6  or  8  days  and  can  then  be  delivered 
on  the  job.  The  blocks  are  not  thoroughly  set  in  that  time,  but 
they  are  sufficiently  permanent  to  be  used  with  perfect  safety 
in  case  of  emergency.  However,  this  hastening  procedure  is 
not  to  be  recommended  except  in  case  of  immediate  need.  As 
a  rule  the  first  curing  method  is  used,  taking  the  blocks  from 
steam  room  in  24  hours  and  storing  for  from  60  to  90  days. 

For  mortar-blocks,  made  of  cement  and  sand,  a  1  :  4  mixture 
is  common.  For  cement,  sand,  and  broken  stone  or  gravel, 
1  :  2  :  4  is  perhaps  an  average.  The  proper  proportion  of  in- 
gredients, as  in  all  concrete  work,  requires  that  every  grain  of 
sand  be  coated  with  cement,  and  that  every  piece  of  aggregate 


254        FIRE   PREVENTION   AND   FIRE   PROTECTION 

be  coated  with  the  sand-cement  mortar.  "  Wet"  and  "medium" 
grades  of  blocks  are  less  porous  and  hence  generally  preferable 
to  the  "dry"  mixture  blocks. 

Fire  Tests  of  Mortar-blocks.  —  For  a  detailed  account  of  fire 
and  water  tests  on  mortar-blocks,  see  United  States  Geological 
Survey  Bulletin  No.  370,  regarding  tests  made  at  the  Under- 
writers' Laboratories.  Thirteen  panels  of  mortar-blocks  were 
tested,  including  blocks  made  with  five  distinct  types  of  machines, 
with  varying  proportions  of  ingredients,  and  of  damp,  medium 
and  wet  consistencies.  A  general  summary  of  the  tests  is  as 
follows : 

It  is  apparent  that  the  strength  of  the  webs  of  ordinary 
hollow  blocks  is  insufficient  to  resist  the  stresses  set  up  in  these 
tests,  as  in  many  tests  the  rapid  rise  in  temperature  and  the  sub- 
sequent quenching  of  one  of  the  faces  of  the  blocks  caused  the 
webs  to  split.  It  was  noticeable  that  the  richer  the  mortars 
used  in  these  blocks  the  better  they  withstood  the  tests.  The 
amount  of  water  used  in  mixing  the  mortars  had  a  similar  effect 
on  the  fire-resistive  qualities;  the  mortars  mixed  with  the  great- 
est percentage  of  water  gave  the  best  results.  This  may  be 
clearly  seen  in  the  photographs  of  the  mortar-blocks  after  the 
water  treatment,  where  the  wetter,  richer  mixtures  often  stand 
out  apparently  undamaged,  in  contrast  with  the  spalled,  damaged 
faces  of  the  leaner,  drier  blocks. 

When  blocks  were  cracked  or  spalled  before  the  application 
of  the  water,  the  damage  appeared  to  be  greater  in  the  dry 
mixtures  containing  the  greatest  percentage  of  sand,  and  it  was 
further  observed,  during  the  fire  test,  that  the  richer  mixtures 
warmed  up  more  slowly  than  the  others.  It  is  apparent  that 
one  of  the  causes  of  weakness  in  the  hollow-cement  building 
blocks  under  these  fire  tests  was  the  weakness  of  the  concrete, 
a  too  dry  and  lean  mixture,  which,  coupled  with  the  thinness  of 
the  webs,  provided  insufficient  strength  to  resist  the  stress  due 
to  the  rapid  expansion  of  the  face.  It  is  quite  possible,  as  was 
shown  in  some  of  the  block  tests,  to  make  blocks  which  will 
pass  the  conditions  perfectly;  the  web  must  be  thick  enough  to 
give  the  necessary  strength. 

Conductivity  of  Mortar-blocks.  —  An  average  of  all  the  tests 
shows  that  about  90  per  cent,  of  the  maximum  temperatures  at- 
tained by  the  faces  of  the  panels  was  reached  in  one  hour,  while 
in  the  case  of  the  mortar-blocks,  the  increase  in  temperature  of 
the  backs  of  the  panels  in  one  hour  was  only  about  20  per  cent, 
of  the  total  increase  in  the  two  hours. 

Requirements  for  Fire  resistance*  —  The  highest  fire  resistance 
will  be  found  in  concrete-  or  mortar-blocks  made  with 

*  Recommended  by  the  National  Fire  Protection  Association  Committee  on 
"Cement  for  Building  Construction,"  1907. 


MATERIALS    OF    FIRE-RESISTING    CONSTRUCTION      255 

1.  The  thickest  shell,  or  being  nearest  solid.      Should  never 
be  less  than  2  inches  thick. 

2.  A  good  brand  of  Portland  cement,  tested  to  conform  to 
recognized  standards. 

3.  One  part  cement  to  not  more  than  four  parts  sand  or  other 
aggregate. 

4.  The  wettest  mixture  practicable. 

5.  Careful  curing  or  aging,  to  continue  for  not  less  than  thirty 
days  before  using,  during  which  time  the  blocks  are  frequently 
moistened  by  water  spray  or  steam. 

6.  Solid  courses  of  blocks  on  which  joists  or  girders  may 
rest,  instead  of  allowing  beams  to  rest  on  or  hang  to  the  inner 
side  of  a  hollow  shell  which  may  break  off. 

Mortars  and  Plasters.  —  All  grades  of  mortars  and  plasters, 
from  common  lime-  and  sand-mortar  to  the  highest  grades  of 
patent  and  cement  plasters,  are  used  for  fire-resisting  purposes 
in  various  forms  of  light  interior  constructions.  These  have 
been  called  into  existence  by  false  notions  of  economy  as  to 
original  cost  and  space  occupied.  Many  of  the  hard  mortars 
and  patent  plasters  when  applied  to  light  metal  frameworks 
and  metal  lathing  have  proved  by  experience  to  be  more  or  less 
useful,  according  to  the  intensity  and  duration  of  the  exposure; 
but  the  ultimate  disintegration  becomes  simply  a  question  of 
intensity  and  time,  and  the  use  of  such  constructions  should  be 
governed  by  discrimination. 

Plaster  is  largely  used  with  wire  netting  or  metal  lathing  for 
the  protection  of  columns  and  beam  flanges  and  as  suspended 
ceilings,  but  experience  has  shown  that  unless  the  plastering  is 
well  pressed  through  to  the  reverse  side  of  the  netting,  it  will  all 
soon  drop  off,  especially  under  the  action  of  water.  In  cases 
where  the  netting  or  metal  lath  hugs  the  metal  member  closely, 
there  is  no  room  for  the  plaster  on  the  inner  side,  and  as  soon  as 
the  outer  layer  drops  off,  the  metal  is  left  exposed.  To  be  even 
partially  efficient,  a  space  should  be  provided  between  the 
netting  or  lath  and  the  metal  member  to  be  protected,  and  this 
space  should  then  be  completely  filled  with  plaster. 

For  discussion  of  the  fire-resisting  value  of  suspended  ceilings, 
see  Chapter  XI. 

Lime-mortar.  —  "As  far  as  actual  resistance  to  intense  heat 
is  concerned,  common  lime-  and  sarid-mortar  in  small  quantities, 


256         FIRE   PREVENTION   AND   FIRE   PROTECTION     ' 

that  is,  when  used  for  the  joints  between  brickwork  or  as  a  plas- 
tering on  a  brick  wall,  has  greater  fire-resisting  qualities  than 
any  other  plastic  material.  It  is  not  uncommon  for  the  surfaces 
of  bricks  to  be  melted  and  the  mortar  joints  to  be  left  standing 
out  from  the  wall  like  a  honeycomb."* 

But  lime-mortar  has  not  sufficient  strength  to  be  used  alone 
in  bodies  thick  enough  to  offer  adequate  fire  resistance.  If  it 
could  be  used  .to  a  thickness  of  four  inches  or  more,  it  would  be 
far  superior  in  fire-resisting  qualities  to  cement-mortar. 

Cement-mortar  or  plaster,  when  exposed  in  considerable  areas 
to  the  action  of  heat,  is  generally  worthless  after  passing  through 
the  ordeal,  provided  even  it  has  answered  its  purpose  of  re- 
stricting the  fire.  The  partitions  in  the  Home  Life  Insuiance 
Building,  which  were  constructed  of  a  light  metal  framework, 
metal  lathing  and  cement-mortar,  showed  that  such  construc- 
tions can  not  be  considered  as  first-class  fire-resisting  methods, 
although  other  cases  may  be  cited,  as  in  the  Livingstone  Building, 
in  which  plaster  partitions  have  been  reasonably  efficient. 

Plaster  Constructions  in  San  Francisco  Fire.  —  "It  may  be 
stated  that  one  of  the  most  obvious  lessons  taught  by  this  fire 
is  the  protection  to  concrete  floors  and  floor  beams  by  the  sus- 
pended ceiling  of  lath  and  plaster.  In  all  cases  where  used,  it 
afforded  complete  protection.  Where  not  used,  concrete  was 
destroyed  and  beams  were  distorted."!  The  plaster  was  com- 
pletely destroyed,  but  the  lath  generally  remained  in  place. 
Hence  such  construction  serves  only  as  a  protection  (whose  de- 
struction is  to  be  expected)  to  the  more  valuable  and  more 
essential  structural  parts. 

Common  plaster  on  wire  mesh,  metal  lath,  or  expanded  metal 
was  very  generally  used  for  the  fireproofing  of  columns,  parti- 
tions and  the  like,  on  account  of  its  cheapness,  but  was  a 
failure  when  subjected  to  a  hot  fire,  as  proved  in  the  Hotel  Fair- 
mount,  the  Hotel  Hamilton  and  several  other  buildings.  This 
failure  was  much  more  noticeable  where  only  a  single  wrapping 
or  thickness  of  the  wire  mesh,  etc.  was  used  than  in  the  case  of 
the  double  wrapping.  But  even  the  latter  proved  to  be  too 
weak  and  disintegrable  to  pass  successfully  through  a  severe 
earthquake  or  a  fire  and  a  strong  stream  of  water  from  a  fire 
hose.  The  plaster  quickly  cracks  and  falls  away  from  the  metal. 
No  doubt  these  materials  will  be  used  in  the  future  by  owners 

*  "What  Constitutes  a  Fireproof  Building  Material."  P.  B.  Wight,  in 
The  Brickbuilder,  September,  1896. 

t  Report  of  Committee  of  Members  of  Am.  Soc.  C.  E. 


MATERIALS   OF  FIRE-RESISTING   CONSTRUCTION      257 

demanding  cheapness  of  construction,  but  they  will  satisfy  the 
requirements  only  in  case  of  mild  exposure.* 

Gypsum  or  Plaster  of  Paris.  —  The  heat-resisting  proper- 
ties of  calcined  gypsum,  commonly  called  plaster  of  Paris,  have 
long  been  known  and  utilized.  In  parts  of  England  where  the 
stone  is  found  in  abundance  it  has  been  used  for  nearly  three 
centuries,  and  in  France  plaster  concretes  made  of  broken  brick, 
wood  chips  and  plaster  of  Paris  have  been  used  for  many 
generations. 

Gypsum  is  a  native  hydrated  sulphate  of  lime,  the  trans- 
parent grades  being  termed  selenite,  and  the  finest  qualities 
alabaster.  The  common  grades  of  gypsum  are  gently  calcined 
until  the  moisture  is  fully  driven  off,  after  which  it  is  ground  to 
produce  plaster  of  Paris.  The  material  possesses  a  very  low 
thermal  conductivity  (see  table  of  tests  on  page  355,  Chapter 
XII). 

Plaster  Blocks.  —  "Pyrobar"  plaster  blocks,  manufactured 
by  the  United  States  Gypsum  Company,  and  Keystone  Fire- 
proof Blocks,  made  by  the  Keystone  Fireproofing  Company,  are 
composed  of  about  95  per  cent,  gypsum  and  5  per  cent,  wood 
fiber  in  the  form  of  excelsior.  They  are  quite  extensively  used 
for  partition  construction,  and  for  column  protections,  etc.,  as 
described  in  more  detail  in  Chapters  XII  and  XIII. 

Sackett  Plaster  Board  and  Gypsinite  Studding,  also  made  prin- 
cipally of  plaster  of  Paris,  are  considered  more  at  length  in 
Chapter  XIII. 

Lime-of-Tiel.  —  Several  of  the  older  buildings  which  were 
destroyed  in  the  Baltimore  fire  were  fireproof ed  according  to  the 
system  introduced  into  this  country  from  France  by  the  late 
Leonard  F.  Beck  with.  These  structures  were  among  the  earliest 
attempts  to  produce  a  fire-resisting  construction,  and  the  ma- 
terial employed  for  floor  arches,  etc.,  was  called  lime-of-Tiel, 
that  is,  lime  imported  from  Tiel.  The  composite  material  was 
made  of  plaster  of  Paris  and  cinders,  or  plaster  of  Paris  and 
ground  furnace  slag,  with  a  small  proper  Lion  of  lime-of-Tiel 
added.  It  was  known  that  the  latter  material,  which  was  really 
a  hydraulic  cement,  had  an  affinity  for  plaster  of  Paris  (which 
is  not  the  case  with  natural  cements),  thus  making  the  mix- 
ture harder  and  supposedly  more  fire-resisting.  It  proved  so 

*  Prof.  Frank  Soule,  in  United  States  Geological  Bulletin  No.  324,  pp.  148- 

, 


258          FIRE   PREVENTION   AND   FIRE   PROTECTION 

ineffectual,  however,  that  lime-of-Tiel  compositions  have  not 
been  manufactured  for  many  years.  In  the  Baltimore  fire  the 
lime-of-Tiel  floor  arches  in  the  Baltimore  and  Ohio  Railroad 
Company's  Building  were  largely  sagged  and  broken,  and  the 
girder  and  column  protections  of  the  same  material  in  the 
Equitable  Building  were  wholly  inefficient. 

Fire-resistance  of  Plaster  Blocks.  —  In  the  partition  tests  con- 
ducted by  the  New  York  Building  Department  (see  Chapter 
XIII),  several  types  of  plaster-block  partitions  were  subjected 
to  fire  and  water  tests.  While  none  permitted  the  passage  of 
flame,  all  were  so  injured  as  practically  to  require  replacement. 
In  every  case  a  portion  of  the  material  was  washed  away  by 
the  hose  stream.  In  the  case  of  the  solid  plaster  blocks,  the 
material  was  destroyed  to  a  depth  varying  from  i  inch  to  1J 
inches,  while  in  the  two  cases  in  which  cellular  or  hollow  blocks 
were  used,  the  exposed  shells  were  washed  away,  thus  showing 
the  hollow  interior. 

In  the  Baltimore  fire  a  number  of  plaster-block  partitions,  etc., 
proved  practically  worthless.  Thus  the  partitions  in  the  Herald 
Building  made  of  this  material  were  mostly  displaced,  crumbled 
and  powdery.  Those  still  standing  were  soft  and  lifeless,  and 
one's  finger  could  easily  be  pushed  into  the  blocks.  The  re- 
port of  the  National  Fire  Protection  Association  states  that  "the 
total  failure  of  the  plaster-block  partitions  was  conspicuous,  as 
they  softened  and  crumbled  away  completely  under  heat." 

The  only  plaster  of  Paris  construction  which  the  writer  knows 
of  as  occurring  in  the  San  Francisco  buildings  was  in  the  Acade- 
my of  Sciences  Building  where  "plaster  of  Paris  was  used  on 
the  concrete-filled  cast-iron  columns,  and  seemed  to  stand  fire 
much  better  than  lime-mortar." 

Sorel  Stone,  otherwise  called  "Sorelite,"  "Sorellith,"  "Mag- 
nolith,"  "marbleite,"  "marbleoid,"  "marbolith,"  "asbestolith," 
"wood-stone,"  etc.,  is  an  artificial  stone  or  marble-like  compo- 
sition, chemically  known  as  an  "oxy chloride  of  magnesium  " 
product.  It  was  invented  in  1853  by  one  Sorel,  a  French 
chemist,  who  patented  it  in  the  United  States  in  1870,  since 
which  various  modifications  of  the  basic  patent  or  principle 
have  been  employed  for  a  wide  variety  of  purposes  under  many 
names,  including  those  given  above,  and  others.  Some  of  the 
principal  uses  of  sorel  stone  have  been  artificial  building  stones, 
artificial  marble,  tiling,  wainscoting,  base,  mouldings,  etc.,  but 


MATERIALS   OF   FIRE-RESISTING   CONSTRUCTION      259 

its  chief  use  has  been  in  the  manufacture  of  monolithic  floors, 
as  described  in  the  following  paragraph. 

The  aggregates  employed  depend  entirely  upon  the  uses  to 
which  the  material  is  to  be  put.  They  include  powdered  stone, 
sand,  powdered  quartz,  asbestos  (either  fiber  or  powdered), 
powdered  talc,  mineral  wool,  sawdust,  ground  cork  or  ground 
shells.  To  any  proper  combination  of  these  aggregates  is  added 
powdered  calcined  magnesite  as  the  base  of  the  cement.  The 
mass  is  then  moistened  with  a  solution  of  chloride  of  magnesia, 
and  coloring  matter  is  added,  if  desired.  The  material,  when 
set,  is  sorel  stone. 

Tests  made  by  the  New  York  Building  Department  showed 
that  this  material  possesses  superior  fire-resisting  properties. 
Samples  of  flooring  mixtures,  j  inch  thick,  were  subjected  to 
flame  at  a  temperature  of  1700°  F.  for  one-half  hour,  after  which 
they  were  plunged  into  a  60-pound-pressure  water  stream  for 
one  minute,  without  warping  or  cracking.  While  the  face 
showed  a  temperature  of  1700  degrees,  the  opposite  side  showed 
only  226  degrees,  thus  proving  the  great  non-conductivity  of 
the  material. 

Monolithic  Floors.  —  Many  modifications  of  sorel  stone,  as 
described  in  the  preceding  paragraph,  have  been  widely  experi- 
mented with  in  an  endeavor  to  obtain  a  satisfactory  monolithic 
flooring  which  should  be  fire-resisting,  elastic,  impervious  to 
water  and  acids,  durable  and  withal  not  too  expansive;  and 
while  some  manufacturers  have  failed,  either  through  the  crack- 
ing, warping  or  buckling  of  the  material,  others  have  secured 
most  excellent  results. 

As  before  explained  in  discussing  sorel  stone,  a  wide  variety 
of  aggregates  is  used,  but  in  general,  such  monolithic  floors  may 
be  divided  into  two  general  classes  —  plastic  floorings  and 
granular  floorings.  Cement  floors  or  monolithic  floors,  made 
with  sand  as  a  base,  are  nearly  always  gritty  or  dusty  under 
wear,  and  the  coloring  matter  in  the  latter  class  of  floorings  is 
very  apt  to  wear  off  and  settle  on  furniture,  etc.  Sand  as  a 
filter  or  base  should  be  avoided,  as  it  also  makes  the  flooring 
brittle,  and  liable  to  crack. 

Monolithic  floors  of  the  better  makes,  such  as  "Karbolith" 
(made  by  the  American  Mason  Safety  Tread  Company),  Asbes- 
tolith,  "Kapailo,"  manufactured  by  the  Kapailo  Manufacturing 
Company,  New  York,  etc.,  are  even  more  durable  than  marble 


260         FIRE    PREVENTION    AND    FIRE    PROTECTION 

or  terrazo,  and  if  properly  laid,  they  will  not  warp  or  crack 
The  writer  knows  of  such  floorings  which  have  been  used  foi 
ten  years  without  showing  signs  of  wear.  They  are  resilient) 
and  easier  and  less  dusty  than  cement  floors.  As  they  are  laic 
plastically,  there  are  no  cracks  or  seams  to  accumulate  dirt  01 
germs,  hence  they  are  easily  cleaned,  and,  when  combined  with 
a  coved  or  sanitary  base  of  the  same  material,  are  much  used  in 
hospitals,  etc.  They  are  practically  unaffected  by  acids,  alka- 
lies, blood  or  ink,  and  are  waterproof. 

Monolithic  floors  may  be  laid  over  wood  flooring,  or  over 
concrete  provided  the  latter  is  thoroughly  dry.  The  usua 
thickness  is  about  one-half  inch,  weighing  about  three  pounds 
per  square  foot.  A  variety  of  colors  is  used,  but  the  red  has 
proved  the  most  durable  and  satisfactory. 

Fireproof  Wood,  or,  as  it  should  more  properly  be  called, 
"  fi  re-retardent "  wood,  has  found  building  usage  principally  in 
New  York  City  in  those  structures  exceeding  150  feet  in  height, 
in  which,  according  to  the  Building  Code,  the  floors  must  be 
of  incombustible  material  or  of  "wood  treated  by  some  process- 
approved  by  the  Board  of  Buildings,  to  render  the  same  fire 
proof,"  and  in  which  "all  interior  finish  may  be  of  wood  covered 
with  metal,  or  wood  treated  by  some  process"  as  above. 

Method  of  Manufacture  and  Use.  —  The  treatment  of  fireproof 
wood  by  the  Electric  Fireproofing  Company's  process  consists 
in  placing  the  wood  in  large  steel  cylinders,  to  which  steam  is 
admitted  under  light  pressure.  After  a  time  the  steam  is  with- 
drawn and  a  vacuum  created,  which  draws  the  sap  and  dissolved 
resins  and  gums  from  the  wood.  A  solution  of  phosphate  of 
ammonia  and  sulphate  of  ammonia  is  then  introduced  under 
pressure,  varying  in  degree  according  to  the  size  and  nature 
of  the  wood  to  be  treated,  but  not  exceeding  approximately 
200  pounds  to  the  square  inch.  After  being  thus  impregnated, 
the  wood  is  withdrawn  from  the  treating  cylinder,  exposed  to  a 
certain  amount  of  air  drying,  and  is  then  kiln  dried.  This 
thorough  drying  process,  which  is  very  essential,  leaves  a  portion  ! 
of  the  dissolved  salts  in  the  cellular  structure  of  the  wood,  and 
it  is  these  crystals,  which  will  fuse  under  high  temperatures, 
which  retard  combustion. 

Any  and  all  kinds  of  wood  are  treated,  but  soft  non-resinous 
woods  are  more  easily  and  more  effectually  impregnated.  The 
cost  of  treatment  varies  considerably  with  the  size.  The  usual 


MATERIALS    OF    FIRE-RESISTING    CONSTRUCTION      261 

finish  for  interior  woodwork  is  two  or  three  coats  of  varnish, 
but  wood  exposed  to  the  weather  requires  two  or  three  coats 
of  a  good  metallic  oil  paint. 

Wood  treated  by  the  above  fireproofing  process  appears  to 
take  a  finish  better  than  does  untreated  wood,  owing  to  the  fact 
i  that  it  is  already  filled  by  the  fireproofing  salts,  and,  therefore, 
needs  no  other  preparation  to  fit  it  for  the  application  of  paint, 
i  varnish  or  polish.  There  is  some  question,  however,  whether 
'  the  finish  is  not  more  liable  to  blister  or  check  than  on  untreated 
wood. 

There  has  been  some  trouble  from  corrosion  of  metal  in 
;  contact  where  fireproof ed  wood  has  been  used.  It  would  appear 
i  that  wood  can  be  treated  and  thoroughly  dried  so  that  if  used 
I  in  the  ordinary  dry  atmosphere  generally  found  inside  of  build- 
ings in  our  climate,  it  should  not  give  trouble  from  corrosion.  .  .  . 
Tests  have  been  made  at  the  Stevens  Institute  of  Tech- 
nology and  by  the  Ordnance  Department  of  the  United  States 
;  with  reference  to  weight,  strength,  etc. 

One  test   as  reported  shows  that   the  wood  increased   in 
|  weight  from  34  pounds  per  cubic  foot  to  68^  pounds  after  treat- 
ment, which  again  decreased  to  37 f  pounds  after  kiln  drying, 
that  is,  the  final  gain  in  weight  over  untreated  wood  is  about 
10  per  cent. 

Tests  for  strength  show  approximately  as  follows: 
White  pine  shows  a  gain  in  transverse  or  breaking  strength 
of  7  per  cent. 

Yellow  pine  shows  a  loss  of  transverse  strength  of  12.6  per 
cent. 

Compression  tests  show  a  loss  of  from  6.1  to  9.2  per  cent. 
Tension  tests  show  a  gain  of  19  to  24  per  cent.* 

Fireproof  wood,  especially  that  treated  by  the  Electric  Fire- 
proofing  Company,  has  been  used  in  a  considerable  number  of 
prominent  office  and  store  buildings  in  New  York  City. 

Fire-resisting  Qualities.  —  The  test  applied  to  fireproof  wood 
by  the  New  York  Building  Department  "consists  in  placing  a 
stick  of  the  treated  wood,  f  inch  by  1|  inches  in  cross-section  by 
8  inches  long,  for  two  minutes  over  a  crucible  gas  furnace  in 
which  a  constant  temperature  of  1700°  F.  is  maintained,  then 
removing  the  "test  piece,  noting  the  time  it  continues  to  flame 
and  glow,  then  scraping  away  the  charred  wood  and  determin- 
ing the  percentage  of  unburned  wood."t  The  conditions  of 
acceptance  are  that  "the  flame  and  glow  should  disappear  within 

*  Report  of  Committee  on  Fire-retardent  Treatments  of  Wood,  Proceedings 
)f  Fifth  Annual  Meeting  of  National  Fire-Protection  Association, 
t  Rudolph  P.  Miller,  Superintendent  of  Buildings,  New  York  City. 


262         FIRE    PREVENTION    AND    FIRE    PROTECTION 

ten  to  twenty  seconds  after  the  removal  of  the  test  piece  from 
the  furnace,  and  the  unburned  and  uncharred  section  at  the 
center  of  the  specimen  should  be  not  less  than  50  to  70  per  cent, 
of  the  original  cross-section,  depending  on  the  variety  of  wood 
under  test." 

Other  tests  of  fireproof  wood  have  been  made  by  the  United 
States  Government  (to  determine  its  practicability  for  use  in 
war  vessels),  by  the  British  Fire  Prevention  Committee,  and  by 
the  Insurance  Engineering  Experiment  Station  in  Boston. 
Some  of  the  conclusions  given  by  Prof.  Charles  L.  Norton  in 
Report  No.  XVIII  (1905)  of  the  last-named  institution  are  as 
follows : 

Judged  by  the  average  of  all  the  specimens  examined,  it  is 
clear  that  many  sources  of  ignition  which,  while  lasting  only  a 
few  seconds,  would  set  fire  to  untreated  hard  wood,  must  last  at 
least  five  minutes  to  set  fire  to  fireproof  wood.  The  flame  and 
radiation  given  off  by  fireproof  wood  are  only  a  small  fraction 
of  those  given  out  by  untreated  wood,  and  the  chance  of  spread 
of  fire  along  it  from  the  heat  of  its  own  burning  is  almost  nothing. 
The  deterioration  of  the  wood  when  kept  in  a  reasonably  dry 
place  is  shown  by  the  specimens  of  the  Electric  Company  at 
least,  to  be  almost  nothing  for  a  period  of  three  years,  and  it  is 
my  opinion  that  when  painted  or  varnished  or  even  when,  like 
the  specimens  which  were  kept  for  examination  in  1902,  they  are 
in  the  shape  of  rough  lumber,  the  protection  of  the  electric  process 
is  apparently  permanent.  No  information  is  at  hand,  un- 
fortunately, concerning  the  other  processes,  on  this  point.  .  .  . 

It  was  noted  all  through  the  tests  that  the  fumes  of  the 
burning  wood  were  intensely  pungent,  irritating  to  eyes  and 
throat,  and  caused  in  the  case  of  a  number  of  persons  exposed 
to  them  for  some  days  acute  illness  for  a  short  time.  In  case  of 
fire,  it  is  probable  that  the  firemen  would  find  this  smoke  a 
hindrance  in  entering  and  working  in  a  building  trimmed  with 
fireproof  wood.  The  relative  effectiveness  of  the  treatment  in 
use,  by  at  least  one  of  the  companies  in  1902  and  in  1905,  shows 
that  the  art  has  progressed,  and  that  the  later  specimens  are 
more  fire-retardent  than  the  earlier  ones  were  when  new,  or  are 
at  this  time. 

Asbestos,*  from  a  Greek  work  signifying  " unquenchable," 
(owing  to  the  erroneous  idea  that,  when  once  ignited,  it  could 
not  be  quenched),  is  a  fibrous  variety  of  hornblende  found 
widely  distributed  throughout  the  world.  The  principal  supply 

*  For  a  more  detailed  description,  see  "Asbestos:  Its  Mining,  Preparation, 
Markets,  and  Uses,"  by  E.  Schaaf-Regelman,  The  Engineering  Magazine, 
October,  1907. 


MATERIALS    OF    FIRE-RESISTING    CONSTRUCTION      263 

of  crude  asbestos  suitable  for  the  manufacture  of  woven  fabrics 
comes  from  Canada,  where  it  is  found  in  narrow  veins  or  seams, 
embedded  in  rock,  and  from  which  it  is  easily  severed.  On 
cleavage,  the  asbestos  presents  a  brilliant  dark-green  surface, 
but  after  being  detached,  the  fibers  are  perfectly  white. 

The  process  of  manufacture  begins  with  a  crusher  which 
divides  the  fibers  without  destroying  them,  after  which  they  are 
winnowed  or  cleaned  of  foreign  matter  by  air  blast.  Then,  by 
means  of  a  blower  and  other  processes,  the  fibers  are  sorted  into 
coarse,  medium  and  fine  fibers  of  short  and  long  lengths.  The 
coarser  and  shorter  fibers  are  used  for  a  great  variety  of  manu- 
factured products,  such  as  asbestos  sheathings,  shingles,  pipe 
coverings,  plaster,  etc.  The  finer  and  longer  fibers  are  reserved 
for  weaving  into  asbestos  cloth,  packing,  ropes,  etc. 

Asbestos  is  incombustible  and  is  low  in  heat  conductivity, 
but  after  subjection  to  high  temperatures  it  loses  its  life  and 
becomes  powdery. 

Asbestos-cement  Products,  such  as  asbestos  building 
lumber,  asbestos  corrugated  sheathing,  and  asbestos  shingles, 
are  made  of  hydraulic  cement  and  asbestos  fiber,  in  the  propor- 
tion of  one  part  fiber  to  about  six  parts  of  cement.  The  resultant 
material  is,  therefore,  practically  nothing  more  nor  less  than 
concrete,  in  sheet  form,  which  has  been  subjected  to  heavy 
hydraulic  pressure,  thus  assisting  the  crystallization  of  the 
cement.  The  products  are  then  seasoned  in  suitable  rooms  for 
a  sufficient  length  of  time  before  using. 

Asbestos  board,  manufactured  as  described  above,  was  origi- 
nally intended  as  a  roof  covering  only;  but  its  uses  have  gradually 
extended  to  a  considerable  variety  of  constructive  features,  such 
as  boardings,  sheathings,  shingles,  etc.  These  products  are 
fire-resistive  to  a  very  considerable  degree,  durable,  sufficiently 
elastic  to  endure  vibrations  without  cracking,  and  yet  tough 
under  blows,  etc.  They  may  be  punched,  nailed  and  cut  with 
heavy  tools,  but  cannot  be  worked  with  ordinary  wood-working 
tools.  These  materials  harden  rapidly  with  age. 

Asbestos  Building  Lumber,  or  "  Century  sheathing,"  as  manu- 
factured by  the  Asbestos  Shingle,  Slate  and  Sheathing  Company 
of  Ambler,  Pa.,  can  be  attached  to  studding,  joists,  etc.,  for  use 
on  walls  and  ceilings.  It  is  also  used  for  wainscoting,  doors, 
partitions,  insulations  and,  to  a  considerable  extent,  as  an  ex- 
terior substitute  for  plaster  or  stucco.  By  the  Underwriters' 


264         FIRE    PREVENTION    AND    FIRE    PROTECTION 

Laboratories,  Incorporated,  asbestos  building  lumber  "is  con- 
sidered from  the  insurance  view-point  as  being  superior  to  wood 
for  the  uses  intended." 

" Century  sheathing"  is  made  in  standard  sheets  42  inches  by 
48  inches,  and  42  inches  by  96  inches  in  size,  varying  in  thickness 
from  J  inch  (weight  If  pounds  per  square  foot)  up  to  f  inch 
(weight  6f  pounds  per  square  foot). 

Asbestos  Corrugated  Sheathing  is  really  corrugated  asbestos 
building  lumber,  reinforced  with  a  woven  wire  netting  embedded 
therein.  In  form  it  is  like  corrugated  iron,  and  it  is  used  in 
the  same  manner  as  the  later. 

When  used  in  roof  construction  it  may  either  be  laid  directly 
upon  the  purlins  where  it  is  held  in  place  by  means  of  wires  or 
clips  encircling  the  purlins,  or  it  may  be  nailed  to  wood  nailing 
strips  bolted  to  the  purlins.  For  roofing  purposes  the  side  lap 
should  be  of  two  corrugations,  with  6  inches  for  end  laps.  The 
sheets  should  preferably  be  laid  with  joints  broken  in  every 
course. 

When  used  as  siding  it  may  be  nailed  to  wood  sheathing  or 
wood  nailing  strips,  or  better,  clipped  or  wired  directly  to  the 
steel  construction.  The  side  laps  should  be  two  corrugations, 
with  4-inch  end  laps. 

Standard  size  sheets  are  27J  inches  wide,  i3g-  inch  thick,  and 
lengths  of  4,  5,  6,  7,  8  and  10  feet.  The  weight  is  about  2£ 
pounds  per  square  foot.  The  corrugations  are  2^-inch  pitch. 
The  under  sides  of  the  sheets  are  roughened  to  reduce  conden- 
sation. 

Special  shapes  of  the  same  material  are  made  for  "ridge 
rolls"  at  ridges  of  roofs,  and  for  "corner  rolls"  at  the  vertical 
corners  of  siding. 

Asbestos  roofing  shingles  are  described  in  Chapter  XXI. 

Asbestos  metallic  cloth,  as  used  for  theater  curtains,  etc.,  is 
described  in  Chapter  XXII.  For  one  of  the  most  thorough 
investigations  ever  made  as  to  the  fire  resistance  of  asbestos 
cloth  or  canvas,  and  asbestos  twine  and  rope,  see  "On  the 
Safeguarding  of  Life  in  Theaters,"  by  Mr.  John  R.  Freeman. 

Wire  Glass.  —  Manufacture.  —  The  first  patent  for  wire  glass 
was  granted  in  1855  to  an  Englishman  by  the  name  of  Newton, 
for  "a  fireproof  and  burglar-proof  glass."  No  practical  use  of 
the  invention  was  made,  however,  for  many  years  —  principally 
owing  to  the  difficulties  encountered  in  making  —  until,  in  1893, 


MATERIALS   OF   FIRE-RESISTING   CONSTRUCTION      265 

the  Franklin  Institute  recommended  the  award  of  the  John 
Scott  legacy  premium  and  medal  to  Frank  Shuman  for  his 
machine  and  process  for  producing  wire  glass.  The  varied  uses 
to  which  the  glass  could  be  put,  and  its  superiority  over  ordinary 
glass  were  commented  on,  but  no  special  mention  was  made  of 
its  fire-resisting  qualities. 

The  value  of  wire  glass  as  a  fire-retardent  seems  to  have  been 
discovered  quite  accidentally,  but  as  soon  as  its  use  for  this 
purpose  was  realized,  the  production  was  greatly  stimulated. 
At  first  much  difficulty  was  experienced  in  producing  a  satis- 


Polished 


Cobweb 


FIG.  44.  —  Wire  Glass. 


factory  product,  owing  to  the  "sandwich"  method  of  manu- 
facture followed.  This  consisted  of  pouring  a  melt  of  glass  upon 
a  heated  slab,  and  then  embedding  wire  mesh  therein  while  a 
roll,  traveling  over  the  slab,  rolled  a  second  layer  of  melted  glass 
over  the  mesh.  This  process,  owing  to  the  internal  stresses 
developed  in  the  cooling  of  the  two  layers,  resulted  in  glass  liable 
to  crack  under  changes  in  temperature.  Later  the  improve- 
ment of  " continuous"  or  " solid"  wire  glass  was  developed 
whereby  the  glass  is  made  with  but  one  pouring  and  one  rolling. 
Kinds  and  Sizes.  —  Solid  wire  glass,  made  by  the  Penn- 
sylvania Wire  Glass  Company,  derives  its  name  from  the  im- 
proved process  of  manufacture  described  above.  It  is  rolled  in 
lengths  up  to  130  inches  and  in  thicknesses  from  -j-  to  \  inch, 


266 


FIRE   PREVENTION   AND   FIRE   PROTECTION 


with  surfaces  "polished,"  "figured"  (cobweb  pattern),  "ribbed," 
and  "rough."  The  polished  and  cobweb  types  are  shown  in 
Fig.  44.  The  maximum  width  of  sheets  is  64  inches,  but  sheets 
as  usually  carried  in  stock  are  32  inches  by  130  inches. 

A  distinctive  marking  to  denote  the  approval  of  the  Under- 
writers' Laboratories,  Incorporated,  is  provided  in  the  above 
types  of  solid  wire  glass.  This  consists  of  a  twisted  strand  of 
two  No.  27  gauge  wires,  woven  into  the  mesh  at  intervals  of 
approximately  10  inches,  as  shown  in  one  of  the  vertical  wires 
in  the  polished  light  in  Fig.  44.  In  the  ribbed  pattern  this 
distinctive  marking  cannot  be  seen  when  the  glass  is  inspected 
from  the  ribbed  side,  but  can  be  seen  from  the  plain  side. 

Eighth-inch  and  jVinch  wire  glass  are  not  suitable  for  use 
where  fire  resistance  is  to  be  considered.  For  this  service, 
i-inch  glass  should  invariably  be  used,  and  under  the  rules  and 
regulations  of  the  National  Board  of  Fire  Underwriters. 

Tests  of  J-inch  "solid"  wire  glass,  as  used  for  skylights,  etc., 
were  made  by  Mr.  A.  W.  Kurz,  Engineer  of  the  National  Venti- 
lating Company,  as  follows.  The  lights  were  19  inches  between 
supports,  with  J-inch  bearing  at  each  side.  The  results  indicate 
centrally  concentrated  breaking  loads. 


Tests. 

"  Solid  "  wire  glass. 
"  Continuous  " 
process. 

Old-style  wire  glass. 
"  Sandwich  "  pro- 
cess. 

Number. 
1 

2 
3 
4 
5 

6 

Pounds. 

128 
118 
131 
184 
158 
158 

Pounds. 

75 

90 

85 
74 
103 
81 

Average  .... 

145J 

84f 

High 

184 

103 

Low 

118 

74 

Fire-resistance.  —  Wire  glass  is  largely  used  as  a  fire-retardent 
in  windows,  doors  and  elevator  enclosures,  also  in  skylights 
except  where  the  breakage  of  the  glass  is  desirable  for  the  outlet 
of  flame  or  smoke. 

For  the  particular  application  of  wire  glass  to  windows,  see 
Chapter  XIV,  particularly  the  National  Board  regulations  as  to 


MATERIALS   OF   FIRE-RESISTING   CONSTRUCTION      267 

glazing  on  page  443,  and  paragraphs  "  Wire  Glass  in  Windows," 
"Fire  Tests  of  Wire  Glass  Windows,"  and  "Wire  Glass  Windows 
in  San  Francisco  Fire,"  pages  450,  453  and  455  respectively. 

As  applied  to  stair  enclosures,  see  Chapter  XV,  particularly 
paragraphs  "Metal  and  Wire  Glass  Enclosures  "  and  "Partial 
Enclosures,"  page  506. 

As  applied  to  elevator  enclosures,  see  Chapter  XVI,  particu- 
larly paragraph  "Metal  and  Wire  Glass  Enclosures,"  page  542. 

Diffusion  of  Light.  —  For  comparative  tests  as  to  the  diffusion 
of  light  through  various  kinds  of  glass,  including  prism  and 
wire  glass,  see  Report  No.  Ill,  "Diffusion  of  Light,"  issued  by 
the  Insurance  Engineering  Experiment  Station. 

Prism  Glass.  —  The  following  extracts  are  taken  from  Prof. 
Charles  L.  Norton's  Report  No.  XI  of  the  Insurance  Engineering 
Experiment  Station: 

Purpose  of  Test.  —  The  purpose  of  the  test  was  to  demon- 
strate the  relative  effectiveness,  as  a  fire-resisting  window  glass, 
of  Luxfer  prisms  and  plates  as  compared  with  ordinary  wire 
glass  of  an  approved  make. 

Material  Tested.  —  The  specimens  tested  were  (1st  test)  one 
plate  of  electro-glazed  Luxfer  prisms,  50"  X  50",  0.35  inch  thick. 
Three  lights  of  wired  glass,  24"  X  30",  one-quarter  inch  thick, 
and  one  plate  of  electro-glazed  Luxfer  prisms,  24"  X  30",  0.35 
inch  thick;  and  (2d  test)  one  plate  of  electro-glazed  plate  glass 
50"  X  50";  three  sheets  of  wired  glass  24"  X  30"  X  i";  and  one 
plate  of  electro-glazed  plate  24"  X  30"  X  i".  All  Luxfer  prisms 
and  plates  were  4"  squares. 

It  will  be  noticed  that  the  first  test  was  to  demonstrate 
the  relative  effectiveness  of  the  electro-glazed  prisms  in  50"  X  50" 
and  24"  X  30"  sizes  as  compared  with  the  approved  sheet  of 
wired  glass  of  24"  X  30".  The  second  test  was  to  compare  the 
electro-glazed  plate  in  50"  X  50"  and  24"  X  30"  sizes,  with  the 
24"  X  30"  wired  glass.  .  .  . 

The  openings  in  the  brickwork  to  receive  the  window  frames 
were  as  follows: 

West  side,  54"  X  54";  north  side,  52  J"  X  34"  and  east  side, 
52 J"  X  34".  The  frames  were  of  an  approved  pattern  for  sta- 
tionary sash.  The  metal  was  galvanized  steel  No.  24.  The 
50"  X  50"  lights  were  fastened  to  the  upper  rail  of  the  sash  by 
three  three-sixteenths-inch  bolts  properly  riveted.  .  .  . 

Summary.  —  The  two  tests  resulted  in  demonstrating  the 
ability  of  all  the  samples  tested  to  remain  in  position  and  effective 
operation,  up  to  the  time  when  the  temperature  of  the  melting 
glass  was  reached. 

The  Luxfer  plates  and  prisms  in  24"  X  30"  stood  the  test 
quite  as  well  as  the  24"  X  30"  wired  glass,  and  they  were  stronger 
at  the  close. 


268         FIRE   PREVENTION   AND   FIRE   PROTECTION 

The  Luxfer  plates  50"  X  50"  were  down  nearer  the  fire,  and 
the  glass  was  undoubtedly  hotter  than  the  wired  glass.  But  the 
wired  glass  was  just  at  the  melting  point,  as  shown  by  the 
rounded  edges  of  the  cracks  and  the  distortion  of  the  plate. 

The  results  of  the  two  tests  indicate  that,  as  shown  by 
these  samples,  the  three  materials,  wired  glass,  electro-glazed 
prisms,  and  electro-glazed  plates,  when  used  in  sheets  24"  X  30", 
are  of  practically  the  same  effectiveness  in  resisting  the  action  of 
fire.  The  condition  of  the  50"  X  50"  plates,  during  and  after 
the  test,  shows  them  to  be  as  effective  as  the  24"  X  30"  wired 
glass  sheets,  provided  the  melting  point  of  the  glass  is  not  ex- 
ceeded; and  it  is  certain  that,  at  this  temperature,  all  of  the 
samples  tested  would  completely  fail. 

Asbestos  Protected  Metal  is  a  non-combustible  roofing, 
siding,  and  sheathing  material,  manufactured  under  patents  con- 
trolled by  the  Asbestos  Protected  Metal  Company.  In  brief, 
the  material  consists  of  steel  plates  of  various  gauges,  which 
are  coated  both  sides  under  great  heat  and  pressure  with  a 
special  asphaltum  compound  containing  heavy  natural  oils. 
Layers  of  asbestos  felt  are  then  applied  under  a  high  pressure 
which  results  in  embedding  the  felt  in  the  asphaltum.  The 
sheets  thus  combine  steel  for  strength  and  rigidity,  asphaltum 
for  protection  against  moisture,  deleterious  gases,  etc.,  and 
asbestos  for  resistance  against  heat  or  fire. 

Standard  sheets  are  made  in  the  following  varieties  and  sizes, 
the  steel  plates  or  cores  varying  in  gauge  from  No.  20  to  No.  28, 
U.  S.  standard. 

Flat,  30  ins.  X  96  ins.,  and  30  ins.  X  120  ins. 
Corrugated,  2J-m.  corrugations,  26  X  96  and  26  X  120. 
Beaded  or  grooved  sheets,  28  X  96  and  28  X  120. 
Clapboard  siding,  26  X  60  ins.,  5-in.  face. 
Flat  and  corrugated  ridge  cappings  and  flashings,  etc. 
Interior  finish  sheets,  flat,  any  size  up  to  30  X  144  ins. 

Three  brands  are  manufactured,  —  "Duckback,"  or  water- 
proof, adapted  especially  for  exterior  service,  or  where  moisture 
or  acid  fumes,  etc.,  are  to  be  considered,  —  "Aspromet,"  in 
which  the  asbestos  covering  is  more  or  less  absorbent,  designed 
for  interior  use,  particularly  where  fire  resistance  is  a  factor,  — 
and  special  interior  finish,  in  which  one  side  of  the  sheets  is 
especially  prepared  to  receive  painted  or  enamel  finish,  etc. 
All  of  these  brands  are  made  in  three  colors  —  white,  gray  and 
terra-cotta. 


MATERIALS   OF   FIRE-RESISTING    CONSTRUCTION      269 

These  products  are  used  for  roofing,  siding,  ceiling  and  interior 
sheathing,  etc.,  especially  where  it  is  desired  to  combine  im- 
perviousness  to  moisture,  fumes,  or  gases,  with  some  degree  of 
fire  resistance.  From  a  fire  protection  standpoint  they  are 
decidedly  superior  to  unprotected  sheet  or  corrugated  metals, 
whether  used  as  roofing  or  as  siding;  but  they  are  not  capable 
of  offering  much  resistance  to  either  severe  or  prolonged  heat, 
as  the  materials  will  warp  after  the  thin  protection  layer  of 
asbestos  is  destroyed.  They  are  generally  applied  like  ordinary 
corrugated  iron  —  that  is,  clipped  to  purlins  and  steel  framework. 

"Ferroinclave"  is  a  corrugated  sheet  steel,  designed  to  be 
protected  against  fire  and  weather,  etc.,  by  the  concrete  or  cement 
mortar  which  it  reinforces.  This  product  is  patented  and 
manufactured  by  the  Brown  Hoisting  Machinery  Company 
of  Cleveland,  Ohio. 

Annealed  sheet-steel  of  various  gauges  is  crimped  by  machinery 
to  the  form  shown  in  Fig.  45,  that  is,  with  dovetail  corrugations 

j^— Roof  Covering — ^        


%  ;v^ ':/ i-yj ;-V'.:.V;^ ; /: v'/ ;:.Vi ; ;  C^Vncrete :'; 


FIG.  45.  —  "Ferroiaclave." 

which  are  inversely  tapered.  These  corrugations  are  J  inch 
deep  and  2  inches  center  to  center,  and  of  such  alternating 
widths  that  the  wider  corrugations  on  any  sheet  will  fit  or  "  shin- 
gle" over  the  small  corrugations  of  any  other  sheet,  thus  forming 
a  tight  end  lap  or  joint  without  destroying  the  corrugations. 
Side  lap  is  provided  for  as  shown  in  Fig.  45. 

Ferroinclave  sheets  are  made  2(H  inches  wide,  and  in  lengths 
up  to  10  feet,  the  usual  gauge  being  No.  24.  Weights  per  square 
foot  (not  including  laps)  and  cross-sectional  areas  per  foot  of 
width  for  the  various  gauges  made  are  as  follows: 

No.  28  gauge,       .94  pounds,  .274  square  inches. 

No.  26      "  1.13       "  .329       "  " 

No.  24      "  1.50       "  .439       "  " 

No.  22      "  1.88       "  .548       "  " 

No.  20      "  2.25       "  .658       "  " 


270         FIRE    PREVENTION    AND    FIRE    PROTECTION 

Other  gauges,  galvanized  metal,  and  sheets  with  corrugations 
which  do  not  taper,  are  also  made  to  order. 

The  principal  uses  of  this  material  are  for  roofing  and  siding, 
although  it  has  also  been  used  to  some  extent  for  floor  reinforce- 
ment or  centering,  and  in  stairs,  coal-bins,  silos,  culverts,  etc. 

Ferroinclave  Roofing  is  described  in  Chapter  XXI,  page  685. 

Ferroinclave  Siding  is  constructed  by  fastening  the  sheets  to 
studs  or  girts,  either  vertically  or  horizontally,  but  preferably 
the  latter.  The  supports  may  be  spaced  up  to  9  feet  9  inches 
centers,  but  the  most  economical  spacing  is  usually  4  feet  10i 
inches  centers,  or  two  supports  to  a  standard  10-foot  sheet.  The 
sheets  may  be  held  in  place  by  bolting  through  the  studs  or 
girts,  or  by  clipping.  The  former  method  is  stiffer,  but  in  either 
case,  cross  ties  which  are  furnished  with  the  sheets  should  be 
spaced  about  every  2  feet  at  the  side  laps. 

After  being  placed,  the  sheets  are  plastered,  first  inside  and 
then  outside,  with  \  inch  of  mortar,  thus  making  the  total  thick- 
ness of  siding  1 J  inches.  A  mortar  composed  of  one  part  Portland 
cement,  two  parts  sand  and  a  little  hair  is  recommended.  A 
cheaper  mixture,  generally  satisfactory  except  where  acid  fumes 
exist,  may  be  made  of  one  part  Portland  cement,  one-half  part 
hydrated  lime,  three  parts  sand  and  a  small  quantity  of  hair. 
If  the  span  is  over  7  feet,  a  J-inch  coating  of  mortar  should  be 
placed  on  each  side. 


CHAPTER  VIII. 
PERMANENCY  AND  CORROSION. 

Importance  of  Protection  against  Corrosion.  —  The  ton- 
nage of  structural  steel  used  annually  in  the  United  States  has 
greatly  increased  of  late  years.  In  1910,  2,266,890  gross  tons 
of  structural  shapes  were  produced  by  American  rolling  mills. 
With  the  largely  increased  demand  for  steel  and  fire-resisting 
buildings  comes  the  attendant  question  as  to  the  life  or  per- 
manency of  such  construction. 

The  permanency  of  steel  framework  buildings  as  a  class  by 
themselves  cannot  be  defined  by  any  specific  rules;  general 
locality,  local  conditions  and  constructive  materials  and  methods 
are  all  involved  in  a  proper  solution  of  each  individual  case. 

The  corrosibility  of  metal  work  in  various  classes  of  structures 
is  receiving  increased  attention  from  those  entrusted  with  their 
design.  In  the  past,  and  even  largely  at  the  present  time,  this 
matter  has  been  often  carelessly  dismissed  with  some  very 
general  clause  in  the  specifications,  calling  for  the  covering  of  the 
metal  work  with  one  or  two  coats  of  paint  of  questionable  value. 
Such  a  specification  may  be  regarded  as  one  which  cares  little 
for  the  maintenance  of  the  original  strength  of  a  structure  after 
it  is  erected.  The  effects  of  the  various  building  materials  used, 
upon  the  iron  or  steel  members,  are  seldom  given  serious  thought. 
A  very  large  part  of  the  tonnage  of  steel  used  in  buildings  of  all 
classes  is  designed  without  the  services  of  an  engineer,  and  it  is 
to  be  feared  that  the  average  architect  does  not  appreciate  the 
full  importance  of  adequate  protection  against  deterioration  from 
corrosion  and  kindred  detrimental  influences. 

Relation  of  Corrosion  and  Fireproofing.  —  In  Chapter  VII 
the  fire-resisting  qualities  of  the  materials  ordinarily  used  in 
fire-resisting  construction  have  been  discussed.  Stone,  brick, 
concrete,  terra-cotta,  plasters,  etc.,  have  been  considered  as 
regards  their  fire-resisting  properties  only,  but  the  actions  of 
these  various  protective  coverings  upon  the  embedded  steel 
work,  whatever  its  form  or  function,  must  not  be  overlooked. 

Perfect  fireproofing  requires  the  complete  protection  of  all 
271 


272         FIRE    PREVENTION    AND    FIRE    PROTECTION 

structural  metal  work.  For  this  purpose  many  materials  and 
methods  are  employed.  Several  distinct  grades  of  terra-cotta 
are  in  general  use,  each  having  its  good  or  bad  points  from  the 
standpoint  of  corrosion,  while  various  kinds  of  stones  and  bricks 
also  differ  greatly  in  their  effectiveness  as  protective  coverings. 
Concrete  is  made  in  many  different  mixtures,  and  other  patented 
or  special  products  are  constantly  being  advocated  as  superior 
articles. 

Hence,  in  selecting  materials  for  fireproofing  purposes,  their 
influence  and  action  upon  the  life  of  the  steel  frame  or  other 
metal  work  employed  must  be  given  due  consideration. 

Causes  of  Deterioration.  —  All  metals  suffer  a  diminution 
of  strength,  however  slight  or  slow  in  action,  almost  from  the 
beginning  of  service.  Any  attempt  to  prevent  such  deterio- 
ration, without  a  true  understanding  of  the  cause,  can  only  by 
accident  be  effective. 

The  usual  causes  of  deterioration  in  iron  or  steel  as  employed 
in  fire-resisting  buildings,  are  moisture,  deleterious  chemical 
action,  electrolysis  and  vibrations.  The  deteriorating  ten- 
dencies of  vibration  and  electrolysis  are  matters  for  the  con- 
sideration of  the  architect  or  engineer  entirely  apart  from  the 
question  of  fire  resistance.  Moisture,  in  its  actions  upon  the 
materials  employed,  and  chemical  actions  which  may  arise  from 
the  use  of  certain  materials,  will  alone  here  be  considered  as 
having  any  connection  with  the  fireproofing  of  buildings. 

These  deteriorating  influences  may  arise  from  the  following 
causes : 

Careless  workmanship. 

Imperfect  construction  of  protective  coverings. 

Permeability  of  the  materials  used. 

Chemical  action  of  the  materials  used. 

Leakage  or  radiation  from  piping,  etc. 

Careless  and  Imperfect  Fireproofing  has  to  do  with  the 
methods,  rather  than  with  the  materials  employed.  The  best 
of  materials  may  be  used,  but  faulty  design  or  construction,  or 
carelessness  in  setting,  may  render  useless  the  care  bestowed 
upon  the  selection  of  the  protective  media.  Poor  protection  is 
often  worse  than  no  protection,  in  that  it  covers  up  its  own 
defects  and  allows  the  slowly  but  surely  resulting  deterioration. 

Among  the  more  common  forms  of  imperfect  fireproofing  may 
be  mentioned  inadequate  thickness,  carelessness  in  pointing  up 


PERMANENCY   AND    CORROSION  273 

all  joints,  holes  left  in  the  fireproofing  for  the  passage  of  pipes, 
wires,  tubes,  etc.,  and  the  exposure,  from  any  cause,  of  a  portion 
or  portions  of  the  steel  frame.  These  points  will  be  considered 
in  later  chapters,  but  their  importance  is  to  be  emphasized  as 
influencing  the  ultimate  life  of  the  structure  as  well  as  its  fire- 
resistance. 

Cast-  and  Wrought-iron  and  Steel.  —  Provided  ordinary 
precautions  are  taken,  experience  seems  to  show  that  the  corrosi- 
bility  of  cast-  or  wrought-iron  or  steel  may  be  taken  as  practi- 
cally the  same. 

The  ratio  of  the  exposed  surface  to  the  sectional  area  largely 
determines  the  amount  of  the  corrosion.  In  this  respect,  the 
usual  compact  forms  employed  for  cast-iron  columns  are  superior 
to  the  built-up  forms  of  steel  shapes  with  their  many  joints  and 
pieces  and  connecting  rivets.  But  in  spite  of  the  advantages 
of  cast-iron  as  regards  reduced  area  subject  to  exposure  and 
unbroken  surfaces,  steel  presents  undoubted  superiority  in 
points  of  strength  and  homogeneity  of  composition,  and  proper 
care  exhibited  in  the  design  and  workmanship  will  largely  reduce 
corrosive  tendencies.  Practical  and  constructive  considerations 
also  tend  to  make  steel  the  more  desirable  material,  especially 
in  high  buildings  where  stiffness,  lateral  stability  and  reliability 
become  most  important  elements. 

To  present  a  minimum  area  to  corrosive  influences,  columns, 
either  cast  or  steel,  should  be  designed  in  as  compact  a  form  as 
possible.  The  practice  of  using  very  thin  columns  in  the  ex- 
terior walls,  in  the  form  of  a  plate  girder  set  up  on  end,  as  has 
been  done  in  some  instances,  should  be  avoided.  Such  disposi- 
tion of  the  material  presents  the  greatest  possible  surface  to 
exposure. 

Condition  of  Iron  and  Steel  Found  in  Torn-down  Build- 
ings. —  At  the  time  of  the  earlier  development  of  fire-resisting 
building  construction  in  the  United  States,  especially  during 
the  growth  of  steel  skeleton  methods,  much  doubt  was  expressed 
as  to  the  ultimate  life  of  such  structures.  Even  their  safety 
for  a  brief  term  of  years  was  seriously  questioned.  To-day, 
however,  ample  testimony  exists  as  to  the  behavior  of  protected 
steel  structures  after  varying  periods  of  years. 

Bank  of  the  State  of  New  York.  —  The  building  known  as  the 
Bank  of  the  State  of  New  York,  built  in  New  York  City  in  1855 
or  1856,  was  demolished  in  1903.  The  condition  of  the  crude 


274         FIRE    PREVENTION    AND    FIRE    PROTECTION 

but  effective  wrought-iron  construction  employed,  after  forty- 
eight  years  of  service,  was  as  follows: 

All  of  the  iron  work  appears  to  have  had  two  coats  of  me- 
tallic paint,  probably  iron  oxide.  The  condition  of  this  paint 
covering,  and  of  the  ironwork  in  general,  at  the  time  of  tak- 
ing down  the  building,  was  excellent.  Rust,  where  it  was  to 
be  found  at  all,  was  only  incidental,  in  small  patches  here  and 
there;  but  entire  girders  could  be  found  with  practically  no 
spots  of  rust  whatever.  It  is  to  be  noted  that  both  girders  and 
beams  (joists)  were  surrounded  by  an  air-space,  and  the  lower 
side  of  the  trough-plate  flooring  also  faced  this  air-space.  The 
beams,  with  their  thinner  metal  and  poorer  painting  (in  some 
cases,  at  least),  showed  more  rust  than  the  girders.  The  latter 
were  practically  unaffected.  As  good  an  illustration  of  this 
as  we  could  give  is  afforded  by  the  photograph  of  some  of  the 
girders  in  the  first  floor.  Toward  the  right  may  be  seen  the 
builders'  name,  "  J.  B.  &  W.  W.  Cornell,  143  Centre  St.,"  painted 
in  white  on  the  brown  oxide  paint  of  the  girders.* 

Mutual  Life  Building,  San  Francisco.  —  The  following  deduc- 
tions were  given  by  Mr.  Frank  B.  Gilbrethf  from  his  experience 
in  the  removal  and  rebuilding  of  the  upper  six  stories  of  the 
Mutual  Life  Insurance  Company's  Building,  damaged  by  the 
San  Francisco  fire.  This  building  was  erected  in  1893  and 
restored  in  1906. 

1.  A  steel  frame,  properly  painted  and  buried  in  masonry, 
will  not  rust  enough  in  thirteen  years  to  affect  its  strength  any 
measurable  amount. 

2.  The   better  the   steel  is  coated  with  mortar  the  less  it 
will  rust. 

3.  Portland  cement  is  better  than  lime  mortar  for  imbed- 
ding steel  to  prevent  it  from  rusting. 

4.  Unpainted  iron  rods  buried  in  mortar  composed  of  lime 
and  a  large  proportion  of  Portland  cement  rust  very  little,  cer- 
tainly not  enough  to  impair  their  strength. 

5.  Columns  should  be  of  such  cross-section  that  they  can 
be  thoroughly  imbedded  in  Portland  cement,  avoiding  a  hollow 
column  unless  filled  with  very  soft  concrete. 

6.  Wherever  possible,  preference  should  be  given  to  those 
shapes  of  steel  that  present  the  least  surface  to  the  action  of 
rust. 

7.  If  steel  is  not  thoroughly  cleaned  from  rust  before  it  is 
painted,  the  paint  will  not  greatly  retard  the  progress  of   the 
rust. 

*  See  "Early  Iron  Building  Construction,"  Engineering  News,  September 
10,  1903. 

t  See  Engineering  News,  January  31,  1907. 


PERMANENCY  AND   CORROSION  275 

8.  It  is   much   easier  to  cover  steel  thoroughly  with  con- 
crete than  with  brick  masonry.     If  brick  masonry  is  to  be  used 
the  bricklayer  should  thoroughly  plaster  the  steel  work  ahead 
of  the  brickwork. 

9.  The  quality  of  the  paint  used,  though  important,  is  not 
so  important  as  surrounding  every  part  of  the  steel  with  Port- 
land cement. 

10.  Interior  columns  do  not  rust  as  much  as  exterior  col- 
umns. 

11.  Cinder  concrete  does  not  injure,  to  the  slightest  degree, 
a  steel  floor  beam  that  has  been  painted.     . 

Gillender  Building.  —  The  twenty-story  Gillender  Building 
at  the  corner  of  Nassau  and  Wall  streets,  New  York  City,  was 
the  first  very  high  office  building  to  be  erected  in  that  city  (1896) . 
During  the  summer  of  1910  this  structure  was  demolished,  and 
a  critical  examination  of  the  steel  work,  etc.,  by  Mr.  Maximilian 
Toch  (Lecturer  on  Paint,  Concrete  and  Corrosion,  College  of 
the  City  of  New  York)  led  to  the  following  observations:* 

The  Steel  Well  Preserved.  —  Most  important  of  the  facts 
learned  is  that  the  steel,  per  se,  is  in  a  remarkably  good  state  of 
preservation.  There  may  have  been  a  number  of  rivets  which 
were  largely  corroded,  but  I  was  able  to  find  only  two  that 
showed  anything  like  progressive  oxidation. 

The  Paint  Destroyed.  —  The  specifications  for  the  painting  of 
the  steel,  which  I  obtained  from  Mr.  Charles  I.  Berg,  called 
for  two  coats  of  metallic  paint  in  pure  linseed  oil.  A  very  pecu- 
liar condition  has  occurred  in  this  building,  which,  however,  is 
by  all  means  to  be  expected,  for,  as  I  have  pointed  out  many 
times  before,  linseed  oil  is  totally  unfit  for  the  preservation  of 
steel  which  comes  in  contact  with  cement  mortar  or  any  alka- 
line building  material.  In  the  Gillender  Building  there  is  not  a 
vestige  of  paint  on  the  steel,  and  in  order  to  determine  that 
oxide  of  iron,  or  metallic  brown,  was  used  in  conjunction  with 
linseed  oil,  I  had  to  make  several  microscopic  investigations  of 
pieces  of  mortar  which  had  destroyed  the  oil  but  had  not  de- 
stroyed the  pigment. 

Steel  Preserved  by  Cement.  —  The  main  feature  of  the  pres- 
ervation of  the  steel  was  the  fact  that  the  columns  were  encased 
in  brick  and  a  rich  mortar  or  grout  came  in  contact  with  the 
steel  (which  also  accounts  for  the  complete  destruction  of  the 
linseed  oil).  Wherever  there  was  insufficient  contact  between 
the  grout  and  the  steel,  rust  formed;  but  in  view  of  the  fact  that 
the  construction  of  the  building  was  such  that  moisture  was 
very  largely  excluded,  we  have  only  two  or  three  instances  where 
bad  rust  pitting  took  place. 

*  See  "The  Condition  of  the  Steel  of  the  Gillender  Building;  A  Preliminary 
Report."  Engineering  News,  July  14,  1910. 


276         FIRE   PREVENTION   AND   FIRE   PROTECTION 

These  few  instances  are  mainly  accounted  for  by  the  quite 
peculiar  fact  that  the  columns  which  formed  the  southeast 
corner,  at  the  intersection  of  Wall  and  Nassau  streets,  were 
much  more  rusty  than  the  steel  in  any  other  place.  This  en- 
tire corner  indicated  that  moisture  had  come  through  the  walls. 
On  this  corner,  wherever  there  was  no  close  contact  between 
the  grout  and  the  steel,  progressive  oxidation  took  place.  The 
next  important  rusting  point  of  any  considerable  size  was  at 
the  last  tier  of  beams  and  the  last  columns,  at  the  north  end  of 
the  Nassau  street  side. 

In  1896,  when  this  building  was  being  erected,  damp  re- 
sisting paints  were  in  existence  but  were  not  favorably  known 
to  either  architects  or  builders,  so  that  their  use  had  not  become 
as  general  as  at  the  present  day.  There  is  no  doubt  that  back- 
ing the  stone  would  have  kept  out  sufficient  moisture  to  prevent 
some  of  the  rust  which  the  steel  of  the  Gillender  Building  shows. 

Condition  of  Mortar.  —  It  is  of  further  interest  Bto  note  that 
the  cement  mortar,  which  was  used  for  binding"  the  bricks 
and  rilling  in,  still  shows  a  remarkable  condition.  We  have  all 
been  taught  that  lime  in  a  free  state  carbonates  on  the  surface 
and  forms  a  silicate  on  the  interior,  and  there  is  quite  some 
evidence  to  prove  this  condition.  But  the  formation  of  a  sili- 
cate of  lime  can  evidently  take  place  only  in  atomic  ratio,  for 
which  reason  I  have  always  held  that  in  the  setting  of  cement, 
calcium  hydroxide  is  set  free  and  can  not  combine  with  anything 
else.  This  has  again  been  borne  out  by  the  various  samples  of 
cement  mortar  which  I  have  taken  out  of  the  interior  of  the 
Gillender  Building,  all  of  which  showed  a  rapid  indication  with 
phenolphthalein,  which  proves  conclusively  that  free  lime  was 
present.  .  .  . 

The  one  great  lesson  to  be  learned  from  the  examination 
of  this  steel  is  the  fact  that  those  architects  who  prescribe  a 
cement  mortar  one  inch  thick  around  a  column  of  steel  are  very 
wise  in  their  precautions;  but  linseed-oil  paint  should  not  be 
used  when  such  a  provision  is  made.  There  are  alkali-proof 
paints  which  at  the  same  time  electrically  insulate  and  serve  a 
better  purpose  than  the  linseed-oil  paints. 

Baltimore  "News"  Building.  —  The  condition  of  metal  rein- 
forcement after  being  embedded  for  seven  years  in  a  reinforced 
concrete  structure,  was  strikingly  exemplified  in  the  tearing  down 
of  the  Baltimore  "News"  Building  in  the  early  part  of  1911. 
This  building  was  erected  soon  after  the  Baltimore  fire  in  1904. 
The  concrete  was  a  1  :  2  :  4  crushed  granite  mixture,  and  the 
condition  of  the  reinforcing  steel  was  found,  upon  demolition  of 
the  building  to  make  way  for  a  larger  structure,  to  be  as  follows: 

In  all  but  a  very  few  instances  the  steel  is  in  perfect  con- 
dition, as  fresh  and  as  bright  as  it  was  the  day  it  was  put  in. 
The  reinforcing  rods  are  black  and  smooth  and  show  no  signs  of 


PERMANENCY   AND   CORROSION  277 

rust  or  other  attack,  and  the  I-beams  in  the  grillages  still  carry 
for  the  most  part  the  coatings  of  protective  paint.  The  ex- 
ceptions to  this  general  rule  are  to  be  found  in  a  few  grillage 
beams  where  the  protective  covering  of  concrete  was  only  about 
one-half  inch  and  on  some  floor-  and  roof -slab  rods  which  were 
exposed  to  water. 

The  grillages  are  well  under  the  ground- water  level.  They 
were  protected  only  by  the  concrete  covering  and  that,  in  many 
places,  was  decidedly  thin.  In  these  thin  places  the  water  pene- 
trated to  the  steel  and  despite  the  paint  covering  managed  to 
pit  it  with  the  rust.  In  no  case  is  this  rust  extensive,  but  it  is 
none  the  less  readily  apparent. 

The  roof,  a  three-inch  reinforced-concrete  slab,  was  covered 
with  an  ordinary  slag  roofing.  In  some  places  the  concrete 
appeared  none  too  dense  and  at  such  places  some  of  the  rods 
were  slightly  pitted  with  rust.  It  would  seem  that  the  roofing 
had  leaked  and  the  water  which  had  passed  through  found  some 
weak  places  in  the  concrete,  through  which  it  passed  to  the 
steel.  Similar  leakage  occurred  in  some  of  the  floors  where 
shower  baths  were  in  constant  use,  and  where  the  bath  drain 
floor  was  not  sufficiently  separated  from  the  concrete  floor  slab. 
In  none  of  these  places  had  the  rust  gone  beyond  the  pitting 
stage  so  that  possible  damage  to  concrete  from  the  swelling  of 
a  rusting  rod  cannot  be  observed  on  this  building.  These 
rusted  rods  were  not  to  be  seen  when  the  representative  of  En- 
gineering News  was  on  the  building  and  all  that  is  here  stated 
about  them  is  on  the  authority  of  the  superintendent  for  the 
contractors.  At  any  event,  the  rusted  rods  are  a  very  small 
percentage  of  those  observed,  and  were  in  all  cases  in  slab  rods; 
the  general  condition  of  the  steel  is  perfect.* 

Painting  of  Iron  or  Steel.  —  The  architect  and  the  en- 
gineer are  constantly  clamoring  for  protection  for  the  enormous 
structural  work  under  their  supervision.  More  attention  than 
ever  is  being  paid  to  recent  investigations  on  the  subjects  of 
paints,  and  better  materials  for  painting  purposes  are  being 
insisted  on.  It  is  fair  to  believe  that  those  in  charge  of  engineer- 
ing work  will  demand  in  the  future  vital  improvements  in  steel 
protecting  compounds,  based  on  modern  knowledge  of  the 
problem.  As  has  been  previously  pointed  out,  the  day  of 
empiricism  in  the  selection  of  protective  coatings  has  passed, 
and  the  subject  must  now  be  considered  from  the  standpoint 
of  scientific  investigation  based  upon  a  satisfactory  working 
theory.  The  treatment  of  steel  surfaces  by  the  metallurgist, 
either  by  physical  or  chemical  means,  may  soon  be  developed 
to  such  an  extent  that  metal  will  be  made  almost  non-corrod- 
ible,  but  until  such  a  day  comes  there  will  be  an  immense  de- 
mand for  protective  coatings  that  will  protect,  and  too  much 
attention  and  study  cannot  be  given  to  the  subject.f 

*  Engineering  News,  April  6,  1911. 

t  "The  Corrosion  and  Preservation  of  Iron  and  Steel,"  by  Allerton  S. 
Cushman  and  Henry  A.  Gardner,  page  179. 


278         FIRE    PREVENTION    AND    FIRE    PROTECTION 

The  protection  of  iron  or  steel  in  buildings  will  be  briefly 
considered  under  a  discussion  of  the  following  treatment  of  the 
metal:  Cleaning,  oiling,  painting,  and  protective  coatings. 

Cleaning.  —  All  authorities  agree  that  the  first  requirement 
in  the  protection  of  iron  or  steel  is  the  careful  removal  of  all 
mill  scale,  dirt,  grease  or  rust.  This  initial  condition  is  the  most 
difficult  to  obtain  of  all  the  requirements  for  efficient  protection, 
as  with  present  mill-  and  shop-methods,  the  cleaning  off  of  scale 
and  the  protection  of  the  material  from  dirt  and  moisture  before 
an  acceptable  priming  coat  is  applied,  are  almost  impossible  to 
accomplish  thoroughly.  The  practice  of  storing  structural  steel 
in  the  open  for  varying  periods  of  time,  both  at  the  mill  and  at 
the  fabricating  shop,  as  well  as  in  transit  when  mill  and  shop  are 
at  different  locations,  makes  it  well-nigh  impossible  to  obtain 
perfectly  bright  and  clean  material  for  painting.  Even  the 
average  inspection  of  painting  is  more  or  less  superficial,  and 
more  attention  is  generally  paid  to  the  uniform  coloring  of  the 
surface  than  to  the  condition  of  the  surface  itself.  Painting 
specifications  should  require,  and  inspection  should  demand, 
that  all  structural  steel  should  be  free  from  scale,  rust  and  dirt 
before  the  priming  coat  is  applied. 

Oiling.  —  A  shop  or  priming  coat  of  raw  or  boiled  linseed 
oil,  has,  in  past  years,  largely  been  specified  for  structural  steel 
work  before  shipment.  Boiled  oil  has  usually  been  preferred 
to  the  raw,  as  the  latter  does  not  dry  quickly,  but  remains 
sticky  for  a  considerable  time,  thus  gathering  dirt  and  cinders 
in  transportation.  Boiled  oil  has  generally  been  considered 
thoroughly  efficient  as  a  priming  coat,  and  has  been  popular 
because  it  forms  a  transparent  protective  covering,  thus  leaving 
visible  defects  which  might  have  escaped  detection  at  the  shop. 
But  recent  investigations  have  shown  that  linseed  oil  is  not 
suitable  for  use  as  a  priming  coat,  nor,  under  certain  conditions, 
as  a  vehicle  for  pigments  in  finishing  coats. 

The  use  of  linseed  oil  as  a  shop  coating  is  not  good  prac- 
tice and  has  probably  been  the  cause  of  much  damage.  Re- 
painting over  such  a  coating,  with  good  results,  is  almost  an 
impossibility.  When  a  linseed  oil  film  on  iron  is  abraded  at 
any  point  on  the  surface,  corrosion  will  proceed  rapidly.* 

Painting.  —  Up  to  very  recent  years,  past  practice  in  con- 
nection with  the  painting  of  steel  work  for  buildings  has  been 

*  Ibid. 


PERMANENCY    AND    CORROSION  279 

confined  to  the  use  of  oil  paints,  such  as  oxide  of  iron,  lead  or 
other  pigments,  ground  and  mixed  with  linseed  oil  or  some  sub- 
stitute therefor,  and  coal-tar,  or  asphalt,  or  mixtures  in  which 
asphalt  is  the  principal  ingredient.  Competent  and  disinterested 
authorities  have  differed  widely  in  their  estimates  as  to  the  value 
of  these  coatings.  While  many  have  recommended  oxide  of 
iron  paint,  others,  equally  qualified  to  advise,  have  advocated 
the  use  of  red  lead,  graphite  or  carbon  paints. 

It  is  only  during  the  past  few  years,  however,  that  any  scientific 
investigations  have  been  made  concerning  the  differentiation  of 
requirements  in  the  painting  or  protection  of  structural  steel 
for  buildings  and  for  other  engineering  structures.  Bridges, 
viaducts  and  other  unprotected  structures,  including  steel 
buildings  such  as  mills  or  shops  where  the  steel  frameworks  are 
unsurrounded  by  masonry,  are  one  proposition,  in  which  the 
inhibitive  qualities  only  of  the  painting  or  protective  coatings 
need  be  considered;  but  in  fire-resisting  buildings,  where  struc- 
tural steel  in  the  form  of  columns,  girders,  beams,  etc.,  is  to  be 
surrounded  by  an  envelope  of  fire-resisting  masonry  or  other 
insulating  coverings,  the  action  of  such  envelopes  upon  the  steel 
and  its  protective  coatings  must  be  considered.  This  applies 
particularly  to  the  action  of  cement  or  cement  mortar  upon 
the  paints  generally  used. 

Protective  Qualities  of  Cement.  —  The  preservative  quali- 
ties of  cement  mortar  surrounding  structural  steel  were  well 
attested  in  the  account,  previously  given,  of  the  demolition  of 
the  Gillender  Building.  Much  other  testimony  of  a  similar 
nature  is  available.  See  also  later  paragraph  "  Concrete." 

Mr.  J.  Newman,  in  his  "Metallic  Structures:  Corrosion  and 
Fouling  and  their  Prevention"  states  that 

Iron  embedded  in  properly  made  and  mixed  water-  and 
air-tight  Portland  cement  concrete  has  not  yet  been  shown  to 
rust,  and  the  preservative  effects  of  such  concrete  may  be  con- 
sidered to  be  established,  provided  the  surface  of  the  metal 
was  clean  and  dry  when  the  Portland  concrete  coating  was  ap- 
plied, and  free  from  corrosion;  and  as  the  expansion  of  cement 
and  iron  by  heat  are  nearly  the  same,  there  is  no  struggle 
between  the  substances  to  cause  cracks,  fissures,  scaling  or  dis- 
integration. 

The  iron  or  steel  should  be  completely  surrounded  by  Port- 
land cement  concrete  of  an  impermeable  character.  For  this 
purpose,  as  the  impermeability  and  not  the  strength  of  the  con- 
crete is  particularly  required,  a  3  of  fine,  dry,  clean  sand,  to 


280         FIRE    PREVENTION    AND    FIRE    PROTECTION 

1  of  Portland  cement,  or  a  2  to  1  mixture,  can  be  adopted,  a 
poorer  concrete  not  being  suitable. 

The  thorough  covering  with  mortar  of  all  possible  portions  of 
the  steel  frame  is  particularly  emphasized  in  the  practice  of 
Messrs.  Holabird  &  Roche,  Architects.  In  their  experience 
with  fireproofing,  they  have  found  that  wherever  the  terra-cotta 
shapes,  etc.,  are  so  arranged  as  to  cover  the  entire  surfaces  of  the 
beams,  girders,  columns,  etc.,  with  the  cement  mortar  in  which 
the  masonry  or  fireproofing  is  set,  practically  no  oxidation  takes 
place,  and  that  such  beams,  girders  and  columns  are  in  perfect 
condition  after  twelve  to  fifteen  years.  On  the  other  hand, 
girders,  beams  and  columns  that  are  simply  protected,  without 
having  the  mortar  in  contact  with  the  steel,  have  frequently 
been  found  seriously  oxidized. 

These  well-attested  protective  qualities  of  cement  mortar  have, 
therefore,  led  some  architects  and  engineers  to  specify  a  one- 
inch  coating  of  1  :  1  cement  mortar  to  be  applied  to  all  surfaces 
of  the  structural  steel  members,  but  this  practice  is  expensive 
and  difficult  of  fulfillment,  as  well  as  questionable,  to  say  the 
least,  from  a  chemical  standpoint  under  certain  conditions. 
Regarding  the  latter  phase,  Mr.  Maximilian  Toch,  whose  report 
on  the  Gillender  Building  has  been  previously  quoted,  stated 
as  follows  in  a  paper  on  the  "  Protection  of  Steel  against 
Corrosion:"* 

It  is  not  my  purpose  to  speak  either  for  or  against  any 

Particular  paint,  and  while  I  personally  do  not  believe  in  lamp- 
lack,  carbon-black  or  graphite  paint  as  a  priming  coat  because 
these  paints  have  withstood  the  ravages  of  the  elements  as 
finishing  paints,  I  am  positive,  from  my  past  experience,  and 
from  pieces  of  steel  which  I  have  seen  uncovered,  f  that  mate- 
rials of  this  character,  when  mixed  with  linseed  oil,  form  practi- 
cally no  protection  for  steel  which  is  to  be  surrounded  by  alka- 
line and  wet  masonry  of  any  kind.  Some  engineers  have  even 
gone  so  far  as  to  require  an  inch  coating  of  cement  mortar,  com- 
posed of  one  part  of  cement  and  one  part  of  sand,  before  either 
the  fireproofing  or  masonry  is  applied  to  building  steel,  but  this 
practice  —  good  as  it  is  theoretically  —  fails  very  frequently 
when .  the  priming  coat  is  a  saponifiable  paint  composed  of 
linseed  oil,  it  being  a  medium  which  is  easily  attacked  by  water 
or  the  alkali  of  concrete. 

*  Read  before  the  New  York  Section  Electro-chemical  Society,  April  2, 
1909. 

t  Compare  with  experience  in  Gillender  Building,  page  275. 


PERMANENCY   AND    CORROSION  281 

If  you  take  the  case  of  a  beam  which  is  placed  in  a  12- 
inch  thick  wall,  and  which  is  coated  with  a  linseed  oil  paint, 
and  then  covered  with  an  inch  of  cement  mortar,  a  driving  rain 
will  go  through  such  a  wall  and  carry  with  it  sufficient  solvent 
salts  to  disintegrate  the  paint  and  leave  a  space  between  the 
steel  and  the  concrete,  and  once  corrosion  starts  in  a  place  of 
this  kind,  we  have  only  to  refer  to  the"  excellent  work  done  by 
Dr.  Whitney  (Journal  American  Society,  Volume  4,  April, 
1903),  which  shows  us  beyond  a  question  that  corrosion  can  be 
progressive  under  such  conditions,  without  the  intervention  of 
additional  gas  or  moisture. 

Protective  Coatings.  —  In  order,  therefore,  to  utilize  the 
protective  qualities  of  cement,  and,  at  the  same  time,  to  over- 
come its  deleterious  action  upon  the  generally  used  linseed  oil 
paints,  a  cement  protective  coating  called  "Tockolith"  has  been 
patented,  and  is  now  finding  wide  use  instead  of  ordinary  paint 
in  the  better  class  of  structures.  This  is  a  thick,  black  liquid, 
composed  of  cement  and  a  binder  which  sets  very  slowly.  When 
the  binder  has  finally  disintegrated,  an  exceedingly  hard  cement 
coating  remains  on  the  steel,  forming  an  efficient  protection 
against  corrosion.  It  is  applied  much  like  any  ordinary  paint, 
but  should  not  be  used  on  damp  surfaces,  nor  in  wet  or  freezing 
weather.  Within  24  to  48  hours  it  becomes  hard  enough  to 
withstand  rough  handling  in  transportation.  The  manu- 
facturers claim  that  it  can  be  applied  over  incipient  rust  without 
depreciating  its  protective  qualities.  This  cement  paint  has 
been  used  as  a  priming  coat  on  the  steel  work  of  the  Metro- 
politan and  Singer  Buildings  and  towers,  the  new  Pennsylvania 
Railroad  Terminal,  the  new  Public  Library  building,  all  in  New 
York  City,  and  on  many  other  prominent  structures  in  various 
localities.  A  finishing  coat  of  damp-resisting  paint  is  applied 
over  the  cement  primer. 

Protection  of  Column  Interiors.  —  The  design  of  iron  or 
steel  columns,  with  respect  to  their  protection  against  corrosion, 
depends  entirely  upon  whether  the  columns  are  to  be  exposed, 
as  in  a  bridge  or  viaduct,  or  protected,  as  in  a  fire-resisting  build- 
ing. If  the  former,  the  section  or  form  of  the  column  should 
preferably  be  open,  so  that  the  interior  may  always  be  accessible 
for  painting.  If  the  latter,  a  closed  form  is  preferable,  in  order 
that  the  entire  exterior  surface  may  be  covered  by  means  of  a 
cement  coating,  or  by  the  mortar,  as  has  been  pointed  out.  If 
a  latticed  section  is  used  in  building  construction,  it  will  be 


282         FIRE   PREVENTION    AND    FIRE    PROTECTION 

found  practically  impossible  to  cover  thoroughly  all  portions  of 
the  metal  work  with  either  cement  or  mortar. 

Present  approved  practice  in  the  design  of  steel  columns  of 
any  considerable  sectional  area  generally  calls  for  a  closed  or 
"box"  form,  usually  made  up  of  plates  and  angles.  Such 
columns  present  fairly  uniform  flat  surfaces  on  the  exterior, 
which  may  be  readily  protected,  as  before  described;  but  the 
protection  of  the  interior  still  remains  to  be  cared  for.  As  a 
usual  practice,  column  interiors  have  not  been  protected,  save 
by  the  one  (or  rarely  two)  coats  of  paint  applied  in  the  shop  at 
time  of  fabrication;  but  careful,  permanent  work,  especially 
when  involving  columns  carrying  heavy  loads,  demands  pro- 
tection in  this  regard. 

This  may  be  accomplished  either  by  filling  the  column  with 
cement  grout  or  cement  concrete,  as  has  been  done  in  many 
cases  (see  also  paragraph  "Concrete-filled  Columns,"  Chapter 
XII),  or  by  painting  the  interiors  by  some  such  expedient  as 
was  adopted  in  the  new  Chicago  Postoffice. 

Many  of  the  columns  were  erected  in  wet  weather  and 
remained  exposed  even  a  whole  winter.  I  deemed  it  advisable 
to  devise  some  means  of  protecting  the  insides  of  the  columns, 
and,  spite  of  much  opposition,  specified  that  they  be  filled  with 
a  thin  grouting  of  cement.  This  was  objected  to,  and  with 
some  justice,  on  the  ground  that  so  much  water  would  have  to 
be  introduced  in  order  to  fill  the  column  through  the  necessa- 
rily small  hole  at  the  top  that  the  chemical  action  of  the  cement 
would  be  impaired  and  more  damage  done  the  column  than  it 
was  sought  to  cure.  The  contractor's  superintendent,  Mr. 
Bodwell,  had  a  happy  thought  and  suggested  that  the  columns 
be  filled  with  a  good,  heavy-bodied  asphaltic  paint  that  could 
be  drawn  off  from  the  bottom  of  each  column  and  thus  leave  a 
thorough  coating  inside.  This,  I  insisted,  should  be  done,  but 
more  opposition  ensued.  Engineers  of  high  repute  asserted 
that  there  was  no  necessity  for  anything  of  the  kind,  that  the 
columns  were  perfectly  dry  inside  and  good  for  all  time,  that  it 
was  a  useless  expense,  etc.,  and  I  was  very  nearly  overruled. 

But  finally  the  work  was  begun,  and  when  the  first  col- 
umn was  bored,  top  and  bottom,  a  lot  of  experts  gathered  to 
see  the  fun  and  give  me  the  laugh,  but  the  tables  were  turned, 
for  from  that  very  first  column  five  bucketsful  of  water  were 
taken ! 

Most  of  these  columns  are  thirty  feet  or  more  in  length, 
extending  through  two  stories  of  the  building  and  'breaking 
joints.'  The  paint  was  poured  in  from  an  inch  hole  (a  rivet 
hole)  at  the  top,  and  drawn  off  from  the  bottom.  Some  fifteen 
pounds'  pressure  drove  this  paint  into  every  crevice  and  chink, 


PERMANENCY   AND    CORROSION  283 

and  about  six  gallons  per  column  was  the  quantity  of  paint  that 
'stuck.'  The  holes  were  riveted  up  and  the  insides  of  those 
columns  are  now  absolutely  hermetically  sealed,  all  moisture 
expelled,  and  coated,  so  that  we  can  be  perfectly  sure  that  that 
part  of  the  work  is  good  for  all  time.  * 

Permeability,  Porosity  and  Chemical  Action  of  the 
Materials  Employed.  —  The  permeability  of  matter  is  that 
property  which  allows  the  passage  of  moisture.  Porosity  con- 
cerns the  absorption  of  moisture.  In  building  materials  which 
are  used  to  surround  steelwork,  it  is  desirable  to  have  the  least 
possible  permeability,  in  order  that  a  minimum  of  moisture  may 
penetrate  to  the  steelwork. 

The  permeability,  porosity  and  chemical  action  of  the  ma- 
terials usually  employed  in  fire-resisting  construction  may  be 
discussed  under  the  following  divisions:  Mortars,  masonry, 
terra-cotta,  and  concrete. 

Mortars.  —  "The  greatest  porosity  in  cement  mortars  is 
found  with  the  finer  grades  of  sand,  and  the  least  for  a  mixture 
of  two  of  very  coarse  (gravelly)  sand  to  one  of  fine  sand.  The 
relative  permeability  cannot  be  assumed  to  vary  with  the  poros- 
ity, since  a  given  degree  of  porosity  with  coarse  sand  produces 
a  much  more  permeable  mortar  than  the  same  degree  of  porosity 
with  fine  sand."t 

In  general,  it  may  be  stated  that  mortars  made  with  coarse 
sand  are  more  permeable  than  those  made  with  fine  sand,  while 
mortars  made  with  fine  sand  are  more  porous  than  those  made 
with  coarse  sand. 

The  permeability  of  cement  mortar  decreases  with  the  pro- 
portion of  cement  used,  and  with  the  age  of  the  mortar.  A  good 
Portland  cement  mortar  becomes  practically  impermeable  a  few 
months  after  setting. 

Both  the  permeability  and  porosity  of  lime  mortars  are  greater 
than  for  cement  mortars. 

Cement  Mortar.  —  The  protection  of  iron  or  steel  when  sur- 
rounded by  cement  mortar  is  discussed  under  previous  headings, 
"Condition  of  Iron  and  Steel  found  in  Torn-down  Buildings," 
"Protective  Qualities  of  Cement,"  etc.,  and  in  a  later  paragraph 
"Concrete." 

Lime  Mortar.  —  The  effects  of  lime  mortar  on  iron  or  steel- 
work seem  to  be  largely  dependent  upon  the  peculiar  conditions 

*  F.  W.  Fitzpatrick,  in  Fireproof  Magazine,  December,  1903. 
t  "The  Materials  of  Construction,"  by  J.  B.  Johnson,  page  59L 


284         FIRE    PREVENTION    AND    FIRE    PROTECTION 

attending  its  use.  Many  cases  have  been  recorded  where  metal 
was  found  badly  corroded  after  being  embedded  in  lime  mortar, 
while  equally  authentic  reports  have  been  made  tending  to  show 
that  lime  mortar  is  an  excellent  conservator  of  iron. 

In  the  demolition  of  the  Pabst  Building  in  New  York  City 
it  was  found  that  "in  some  special  partitions,  where  made 
with  'metallic  lathing  plastered  with  lime  mortar,  the  lath  was 
badly  rusted,  although  the  partitions  were  otherwise  in  good 
condition/'* 

Patent  or  Hard  Wall  Plasters  will  generally  corrode  light  metal 
work  used  therewith,  such  as  expanded  metal  or  meth  lath, 
unless  the  latter  are  sherardized  or  galvanized. 

Masonry.  —  The  previously  given  description  of  the  steel- 
work in  the  demolished  Gillender  Building  shows  that  metal 
work  embedded  in  brickwork  or  masonry  is  not  necessarily  free 
from  air  and  moisture,  nor  is  it  proof  against  corrosion  simply 
because  it  was  coated  with  ordinary  paint  before  being  covered 
in.  All  thin  masonry  walls  are  more  or  less  permeable,  and 
weather  influences  and  vibration  will  cause  the  mortar  in  the 
joints  to  crack  and  open.  Each  new  fissure  becomes  an  added 
conduit  by  which  moisture,  air  and  other  corrosive  influences 
can  reach  the  metal.  Proper  materials,  adequate  thickness  and 
an  occasional  pointing  of  the  joints  are  all  necessary  for  the  less- 
ening of  deleterious  action.  Very  efficient  damp-resisting  paints 
are  now  made  for  use  on  interior  wall  surfaces,  etc.  "  However, 
if  ironwork  is  free  from  any  corrosion  when  placed  in  position, 
and  is  properly  cleaned  before  it  is  coated,  and  is  fixed  in  air- 
tight, damp-proof  and  water-tight  brickwork  or  masonry,  it  is 
unlikely  to  corrode  appreciably."!  This  has  been  shown  to  be 
true  by  ample  experience. 

In  brickwork,  underburnt  soft  bricks  soon  decay  in  damp 
situations.  Bricks  which  are  dense,  hard,  even  in  texture,  and 
with  a  vitrified  appearance,  will  resist  decay.  The  uniformity, 
density,  and  weathering  qualities  should  all  be  considered. 
Some  bricks  contain  a  large  percentage  of  soluble  salts.  Efflores- 
cence denotes  a  decay,  which  is  formed  by  the  decomposition  of 
the  salts  in  the  brick  or  stone. 

The  use  of  veneer  walls  in  skeleton  construction  has  often  re- 
sulted in  the  employment  of  masonry  coverings  of  very  doubtful 

*  Editorial,  Engineering  Record,  January  31,  1903. 

t  "Metallic  Structures:  Corrosion  and  Fouling,  and  their  Prevention," 
by  J.  Newman. 


PERMANENCY   AND    CORROSION  285 

protection.  One  of  the  requisites  in  high-building  design  is  to 
secure  walls  of  less  than  usual  thickness,  on  account  of  the 
attendant  reduction  in  weight.  In  some  cases  the  metal  frame- 
work has  been  surrounded  by  no  more  than  four  inches  of 
brickwork.  Such  thin  coverings  are  not  adequate  as  regards 
either  fire-resistance  or  corrosion. 

Limestone  should  not  be  employed  in  contact  with  steelwork 
where  the  presence  of  moisture  is  probable  or  possible.  Mr.  L. 
L.  Buck,  Chief  Engineer  of  the  Niagara  suspension  and  arched 
bridges,  states  that  limestone  must  not  be  used  in  concrete  which 
comes  in  contact  with  iron  or  steel,  as  the  corrosion  of  the  metal 
will  follow  if  moisture  penetrates.  In  the  anchorage  of  the 
Niagara  suspension  bridge,  strands  of  the  main  cables  were 
embedded  in  a  concrete  made  with  limestone,  and  wherever  the 
spalls  touched  the  wires,  the  latter  were  badly  eaten  and  in  some 
cases  entirely  severed.  If  it  is  necessary  to  use  limestone,  it  is 
better  to  place  a  layer  of  pure  cement  mortar  or  an  extra  thick- 
ness of  asphalt  around  the  steelwork. 

Terra-cotta.  —  The  density  of  terra-cotta  is  the  important 
factor  in  determining  its  porosity  and  absorption.  Thus  very 
hard  burned  terra-cotta  will  absorb  about  5  per  cent,  of  its  weight 
when  immersed  in  water.  Merchantable  hard  burned  terra- 
cotta absorbs  about  13  to  15  per  cent,  when  similarly  treated. 
Very  porous  soft  terra-cotta  absorbs  from  30  to  40  per  cent.,  and 
merchantable  terra-cotta  about  25  to  30  per  cent.  But,  while 
the  hard  stock  absorbs  about  13  per  cent.,  and  the  porous  stock 
about  25  per  cent.,  the  hard  stock  will  require  about  twice  as 
much  heat,  or  the  same  amount  of  heat  and  twice  as  much  time, 
to  permit  the  evaporation  of  the  lesser  amount  of  absorbed 
moisture. 

This  is  accounted  for  by  the  fact  that  in  hard  burned  terra- 
cotta the  air  channels  are  smaller,  and  as  the  material  is  of  a 
laminated  nature,  the  cells  in  the  blocks  run  lengthwise,  and  heat 
cannot  easily  penetrate  the  surface.  Also,  the  heat,  in  com- 
ing in  contact  with  the  hard  smooth  surface,  is  reflected,  and 
the  interior  of  the  block  is  not  affected  as  readily  or  as  much 
as  is  the  case  in  a  more  porous  material.  In  porous  terra-cotta, 
reverse  conditions  are  found.  The  material  is  of  a  granular 
nature,  instead  of  laminated;  the  air  channels  extend  in  from  the 
surface,  and  the  surface,  being  neither  hard  nor  smooth,  tends 
rather  to  absorb  heat  than  to  reflect  it. 


286         FIRE    PREVENTION   AND    FIRE    PROTECTION 

But,  aside  from  the  absorption  of  the  material  after  being; 
placed,  it  is  to  be  remembered  that  a  considerable  quantity  of 
water  is  used  in  the  setting,  and,  although  the  cement  mortar 
will  use  a  portion  in  crystallization,  a  surplus  remains,  and  largely 
upon  the  inner  or  cooler  side.  The  hard  stock  will  neither 
absorb  it  nor  permit  evaporation.  With  porous  stock,  the 
moisture  is  soon  removed. 

Summarizing  the  foregoing,  it  is  seen  that  a  very  porous 
material  is  much  to  be  preferred  as  an  insulation  against  damp- 
ness, and  this,  independent  of  the  superior  fire-  and  water-resist- 
ing qualities  which  this  material  possesses. 

The  employment  of  terra-cotta  casings  around  the  columns 
placed  in  the  exterior  walls,  between  the  metal  and  the  masonry, 
as  now  called  for  in  the  best  examples  of  work,  will  undoubtedly 
add  to  the  life  of  the  columns. 

Concrete.  —  It  has  been  shown  that  no  more  effective  manner 
of  protecting  steelwork  is  known  than  by  embedding  in  proper 
cement  mortar,  and  the  same  may  be  said  of  concrete  within 
certain  unfixed  limitations. 

The  previously  quoted  extract  from  Mr.  Newman's  work 
on  corrosion,  while  applying  particularly  to  cement  mortar,  is 
equally  applicable  to  concrete.  Indeed,  in  the  quotation  re- 
ferred to,  that  author  seems  to  use  the  words  mortar  and  concrete 
synonymously. 

Prof.  Charles  L.  Norton  draws  practically  the  same  conclu- 
sions from  extensive  experiments  concerning  the  protection  of 
steel  from  corrosion,*  viz.t  that  steel  embedded  in  neat  cement 
is  unaffected,  as  is  also  steel  embedded  in  a  dense  Portland  cement 
concrete,  provided  the  latter  is  mixed  wet  enough.  In  these 
experiments  it  was  found  that  a  porous  concrete  apparently 
afforded  poor  protection,  but  the  experience  in  the  demolished 
Pabst  Building,  as  is  mentioned  in  the  following  paragraph  con- 
cerning "  Cinder  Concrete,"  seems  to  controvert  this  conclusion, 
at  least  when  the  exposure  to  moisture  is  not  great. 

The  rusting  of  steel  in  concrete  has  been  made  the  subject  of 
an  investigation  by  the  Concrete  Institute  of  England.  The 
preliminary  report  on  the  subject  is  as  follows: 

A  circular  letter  was  issued  at  the  beginning  of  1909  by 
the  Concrete  Institute,  asking  for  the  results  of  experience  and 
examination  on  the  question  of  whether  rusting  of  steel  takes 

*  See  Reports  Nos.  IV  and  IX,  Insurance  Engineering  Experiment  Station. 


PERMANENCY   AND    CORROSION  287 

place  when  covered  by  concrete.  The  letter  was  sent  to  1000 
engineers  and  others  engaged  in  concrete  construction  —  namely, 
to  members  of  the  Concrete  Institute,  560;  to  municipal  sur- 
veyors and  engineers,  96;  to  engineers  of  joint  water  boards 
and  sewerage  boards,  25;  to  dock  engineers,  38;  to  railway 
engineers,  94;  to  various  contractors  and  others  who  use  con- 
crete, 187.  To  this  letter  111  replies -were  received.  Forty- 
seven  contained  results  of  definite  observations.  In  these  the 
writers  gave  26  cases  of  rusting  which  had  come  under  their 
notice,  and  43  cases  where  no  rusting  has  been  found. 

The  committee  considered  that  the  information  thus  gained 
was  extremely  valuable,  but,  in  order  to  obtain  more  definite  knowl- 
edge of  the  question,  they  personally  examined  certain  structures. 

As  a  result  of  these  observations  and  investigations,  the 
committee  have  drawn  the  following  conclusions.  Reinforced 
concrete  will  last  as  long  as  plain  concrete  in  any  situation  pro- 
vided that  certain  special  precautions  are  taken  during  its  con- 
struction. The  precautions  to  be  taken  are  as  follows: 

Concrete.  —  The  materials  (cement,  sand  and  stone)  must 
be  of  good  quality.  They  must  be  most  carefully  and  thor- 
oughly mixed  and  scientifically  proportioned,  so  as  to  be  prac- 
tically waterproof  and  airproof.  The  mixture  must  be  fairly 
wet  and  must  be  well  punned  into  position  so  as  to  minimize 
voids.  The  aggregate  should  be  as  non-porous  as  possible, 
and  any  aggregate  which  is  known  to  have  a  chemical  action  on 
steel  should  be  avoided.  The  aggregate  should  all  pass  through 
a  f-inch  mesh.  The  concrete  covering  should  in  no  case  be 
less  than  ^-inch,  and  it  is  suggested  that  if  round  or  square 
bars  be  used  the  covering  should  not  be  less  than  the  diameter 
of  the  bar.  In  structures  exposed  to  the  action  of  water  or 
damp  air,  the  thickness  of  covering  should  be  increased  at  least 
50  per  cent.,  or  the  size  of  the  aggregate  should  be  reduced  so 
as  to  ensure  a  dense  skin.  In  the  case  of  structures  exposed  to 
very  severe  conditions,  the  concrete  might  be  covered  with 
some  impervious  coating  as  an  extra  precaution. 

Steel.  —  The  reinforcement  should  be  so  arranged  that 
there  shall  be  sufficient  space  between  one  piece  and  its  neigh- 
bor to  allow  the  concrete  to  pass  and  to  completely  surround 
every  part  of  the  steel.  All  steel  should  be  firmly  supported 
during  the  ramming  of  the  concrete,  so  as  to  avoid  displace- 
ment. It  should  not  be  oiled  or  painted,  and  thick  rust  should 
be  scraped' and  brushed  off  before  placing. 

General.  —  The  scantling  of  the  various  members  of  the 
structure  should  be  sufficient  to  prevent  excessive  deflection. 
If  electric  mains  are  laid  down,  very  great  care  must  be  taken 
that  no  current  is  allowed  to  pass  through  the  reinforced  con- 
crete. Fresh  water  should  be  used  in  mixing,  and  aggregates 
charged  with  salt  should  be  washed. 

These  recommendations  have  regard  only  to  the  preven- 
tion of  corrosion  of  steel  and  not  to  fire-resistance  or  any  other 
property  of  reinforced  concrete.* 

*  The  Engineering  News.  April  6,  1911. 


288         FIRE    PREVENTION    AND    FIRE    PROTECTION 

The  impermeability  of  concrete  depends  principally  on  its  dens- 
ity. The  proportion  of  cement  should  be  in  excess  of  the  bulk 
of  the  voids  in  the  aggregates;  the  mixing  should  be  thorough, 
and  the  concrete  should  be  wet  enough  to  " quake"  when  being 
tamped.  A  still  more  waterproof  concrete  may  be  obtained 
by  using  one  part  of  lime  putty  to  ten  parts  of  cement.* 

The  thickness  of  concrete  required  to  form  adequate  pro- 
tection against  fire  to  the  embedded  steel  (see  Chapter  VII, 
page  249)  is  sufficient  to  secure  protection  against  corrosion. 

Cinder  Concrete.  —  The  action  of  cinder  concrete  upon  iron 
or  steel  embedded  therein  has  been  a  mooted  question  for  many 
years. 

The  following  extracts  are  from  a  report  of  the  executive  com- 
mittee of  the  "  Structural  Association  of  San  Francisco  "f  on 
the  condition  of  metal  embedded  in  cinder  concrete  floors  as 
revealed  in  several  buildings  damaged  or  destroyed  in  the  San 
Francisco  conflagration: 

The  extent  of  the  corrosion  is  great  enough  to  seriously 
endanger  the  safety  of  the  floors,  and  it  is  not  probable  that  the 
floors  would  have  supported  their  loads  more  than  one  to  three 
years  longer.  .  .  . 

Recommendations.  —  That  the  Structural  Association  try 
to  amend  the  present  building  law  so  as  to  exclude  the  use  of 
cinder  concrete  in  floor  slabs  or  for  fireproofing.  That  pro- 
vision be  made  in  the  building  law  for  the  examination  and 
tests  of  any  existing  cinder  concrete  now  in  use  or  that  may  be 
used  at  some  later  period. 

No  definite  causes  for  the  cases  of  corrosion  found  were  deter- 
mined, although  too  dry  mixing  and  the  presence  of  sulphur  and 
unconsumed  coal  were  all  mentioned. 

On  the  other  hand,  the  extensive  experiments  carried  out  by 
Professor  Norton  led  to  the  following  conclusion:  J 

There  is  one  limitation  to  the  whole  question,  that  is  the 
possibility  of  getting  the  steel  properly  incased  in  concrete. 
Many  engineers  will  have  nothing  to  do  with  concrete  because  of 
the  difficulty  in  getting  " sound''  work.  This  is  especially  true 
of  cinder  concrete,  where  the  porous  nature  of  the  cinders  has 
led  to  much  dry  concrete  and  many  voids,  and  much  corrosion. 

*  The  Building  Mechanics'  Ready  Reference,  Cement  Workers'  Edition, 
H.  G.  Richey. 

t  See  Engineering  News,  November  1,  1906. 

J  See  Report  No.  IX  of  Insurance  Engineering  Experiment  Station,  "The 
Protection  of  Steel  from  Corrosion." 


PERMANENCY   AND   CORROSION  289 

I  feel  that  nothing  in  this  whole  subject  has  been  more  mis- 
understood than  the  action  of  cinder  concrete.  We  usually 
hear  that  it  contains  much  sulphur  and  this  causes  corrosion. 
Sulphur  might,  if  present,  were  it  not  for  the  presence  of  the 
strongly  alkaline  cement;  but  with  that  present,  the  corrosion 
of  steel  by  the  sulphur  of  cinders  in  a  sound  Portland  concrete 
is  the  veriest  myth  and,  as  a  matter  of  fact  the  ordinary  cinders, 
classed  as  steam  cinders,  contain  only  a  very  small  amount  of 
sulphur.  There  can  be  no  question  that  cinder  concrete  has 
rusted  great  quantities  of  steel,  but  not  because  of  its  sulphur, 
but  because  it  was  mixed  too  dry,  through  the  action  of  the 
cinders  in  absorbing  moisture,  and  that  it  contained,  therefore, 
voids;  and  secondly,  because,  in  addition,  the  cinders  often 
contain  oxide  of  iron  which,  when  not  coated  over  with  the 
cement  by  thorough  wet  mixing,  causes  the  rusting  of  any  steel 
which  it  touches. 

There  is  one  cure  and  only  one,  mix  wet  and  mix  well. 
With  this  precaution  I  would  trust  cinder  concrete  quite  as 
quickly  as  stone  concrete  in  the  matter  of  corrosion.  It  has 
been  suggested  that  steel  which  has  been  rusted  to  a  slight 
depth  becomes  protected  by  this  coating  from  further  rusting. 
Nothing  could  be  further  from  the  truth.  A  large  number  of 
specimens  were  rusted  by  repeated  alternate  wetting  and  dry- 
ing to  see  if  they  finally  reached  a  constant  condition.  Instead 
of  doing  this,  they  all  showed  an  irregular  but  persistent  loss  in 
weight,  on  further  rusting,  until  some  had  practically  been 
washed  away. 

The  increasing  use  of  steel  of  small  dimension  !n  floors  and 
roofs,  twisted  rods,  expanded  metal,  etc.,  has  caused  some 
question  as  to  the  advisability  of  their  use  in  view  of  the  pos- 
sible great  effects  of  corrosion,  as  compared  with  the  effects  of 
corrosion  on  larger  members,  but  with  sound  concrete  of  a 
thickness  of  about  one  and  a  half  inches  between  the  steel  and 
the  weather  I  do  not  question  the  durability  of  these  lighter 
members. 

The  decided  conflict  in  the  above  opinions  led  Mr.  William 
A.  Fox*  to  undertake  a  series  of  experimental  tests  on  bars  of 
steel  embedded  in  cinder  concrete.  Sixty  unpainted  test  pieces 
were  used,  surrounded  by  concrete  made  of  steam  cinders  and 
Portland  cement,  variously  mixed  dry  and  tamped,  wet  and 
untamped,  and  wet  and  tamped. 

After  about  forty  days'  treatment,  the  specimens  were 
broken,  and  the  steel  carefully  examined  for  corrosion.  With 
but  one  exception,  one  or  more  of  the  three  steel  pieces  in  each 
specimen  showed  unmistakable  signs  of  corrosion.  Appar- 
ently .  it  made  no  difference  how  the  concrete  was  mixed  —  wet 

*  See  Engineering  News,  May  23,  1907.' 


290          FIRE   PREVENTION   AND   FIRE   PROTECTION 

or  dry,  tamped  or  untamped;  whether  the  steam  or  water 
treatment  was  used,  the  result  was  the  same  —  rust  streaks  and 
spots  were  found;  the  difference  in  the  amount  of  corrosion 
being  imperceptible.  .  .  . 

To  secure  a  dense  homogeneous  cinder  concrete,  a  thor- 
ough tamping  is  necessary.  A  rich  mixture,  either  a  1  :  1  :  3  or 
one  in  which  the  proportion  of  cement  to  aggregate  is  larger, 
should  be  used  in  all  cases.  The  greatest  of  care  should  be 
taken  in  mixing  the  materials,  and  it  may  be  necessary  to 
resort  to  the  seemingly  impractical  method  of  coating  the  rein- 
forcement with  grout  before  placing  in  the  concrete. 

The  above  tests  and  experiences,  and  many  other  investiga- 
tions which  might  be  quoted,  seem  to  show  that  the  exact  causes 
or  conditions  of  the  corrosion  of  iron  or  steel  in  cinder  concrete 
are  not  fully  understood  either  as  to  nature  or  time.  Thus  some, 
at  least,  of  the  cases  mentioned  by  the  Structural  Association  of 
San  Francisco  may  have  been  due  to  severe  initial  corrosion,  or 
rusting  during  construction  in  rainy  weather;  while  the  tests 
made  by  Mr.  Fox  were  made  on  unpainted  specimens.  Certain 
it  is,  however,  that  enough  satisfactory  data  are  also  at  hand  to 
warrant  the  use  of  cinder  concrete  when  properly  made  and  set. 

Also,  further  reference  to  the  demolished  Pabst  Building  shows 
that  the  wet  mixing  of  cinder  concrete,  emphasized  as  a  re- 
quirement by  Professor  Norton,  is  not  even  necessary  in  all  cases. 

The  beams  and  girders  were  practically  everywhere  en- 
cased in  the  concrete;  this  was  the  cinder  concrete  of  the  floor 
arches,  and  this  fact  should  be  specially  noted  in  view  of  a 
somewhat  prevalent  view  that  cinder  concrete,  especially  when 
placed  so  as  to  have  a  porous  and  open  texture,  is  favorable  to 
corrosion  of  the  steel  with  which  it  is  in  contact.  .  .  . 

The  nature  of  the  floor  concrete  is  of  interest  in  connec- 
tion with  the  matter  of  the  condition  of  the  steelwork.  It  was 
made  and  placed  in  the  manner  regularly  practiced  for  the 
construction  of  floors  of  this  particular  system.  The  proportion 
of  cement  to  cinders  is  smaller  than  is  ordinarily  used  for  con- 
crete, and  the  mixture  is  then  simply  thrown  from  shovels, 
without  ramming,  onto  the  wire-mesh  centering  and  allowed  to 
set.  The  ramming  is  omitted  with  the  object  of  securing  a 
very  porous  concrete,  and  an  important  advantage  claimed  for 
the  material  so  produced  is  that  it  may  be  put  in  place  during 
freezing  weather  without  harm,  as  the  porous  condition  of  the 
concrete  enables  it  to  withstand,  without  cracking,  the  expan- 
sion due  to  freezing  of  the  contained  water.  As  a  matter  of 
fact,  much  of  the  floor  concrete  in  this  building  was  put  in  place 
during  freezing  weather,  we  are  informed.  We  were  interested, 
therefore,  to  note  that  the  concrete  removed  from  the  floors  is 


PERMANENCY  AND    CORROSION  291 

remarkably  hard  and  strong,   and  while  it  is  doubtless  quite 
porous,  a  fractured  face  shows  a  solid  and  firm  surface.  * 

Moisture  from  Pipes.  —  All  piping,  whether  supply,  waste 
or  vent,  should  be  kept  entirely  separated  from  the  steelwork 
and  outside  of  the  fireproofing.  Leakage  from  water-,  waste-, 
or  steam-pipes  will  soon  cause  corrosion  if  the  moisture  reaches 
the  steel.  Sewer  gases  are  also  to  be  guarded  against  as  emanat- 
ing from  vent-pipes.  Additional  considerations  of  piping  in  a 
fire-resisting  building  are  discussed  in  Chapter  IX  in  connection 
with  the  installation  of  the  mechanical  features,  and  in  Chapter 
XII  as  relating  to  column  protection. 

Editorial  in  Engineering  News,  January  29,  1903. 


PART   III 

FIRE-RESISTING  DESIGN 


CHAPTER  IX. 
PLANNING   AND   GENERAL   DESIGN. 

Fire-resisting  Buildings  Defined.  —  By  a  fire-resisting 
building  is  meant  one  in  which  a  fire  starting  within  the  structure 
will  be  confined,  through  the  design  and  the  inherent  qualities 
of  the  building  itself,  to  that  compartment  or  unit  of  area  within 
which  the  fire  originates;  or,  if  subjected  to  attack  by  fire  from 
without,  either  through  an  adjacent  fire  or  wide-spread  confla- 
gration, the  building  must  be  able  not  only  to  protect  its  own 
contents  from  destruction,  but  serve  to  protect  itself  in  all  essen- 
tial particulars,  and  also  to  protect  structures  beyond,  from  the 
further  spread  of  devastation.  Such  attacks  by  fire,  whether 
internal  or  external,  should  result  in  no  material  damage  to  the 
structure  either  in  whole  or  in  part,  except  to  such  surface  or 
standing  finish  as  may  be  easily  renewed.  The  possible  cost  of 
renewal  or  reconstruction  should  be  kept  a  minimum  and  should 
never  constitute  a  large  percentage  of  the  cost  of  the  building. 

And  at  the  outset,  in  considering  how  to  attain  these  results, 
it  is  well  to  face  two  indisputable  facts: 

First,  that  there  is  no  ultimate  economy  in  poor  fireproofing. 
Either  fireproof  well  or  not  at  all,  as  the  slight  excess  cost  of 
good  and  sufficient  materials,  careful  workmanship  and  adequate 
inspection,  all  applied  to  a  proper  initial  design,  will  pay  for 
itself  many  times  over  when  the  final  test  comes.  The  question 
of  efficiency  vs.  faulty  construction  is  considered  in  detail  in 
Chapter  X.^ 

Second,  that  the  fire-resisting  qualities  of  a  proposed  building 
must  be  both  carefully  and  scientifically  considered  and  planned, 
exactly  as  the  proposed  use  to  which  the  building  is  to  be  put  is 
considered  in  the  design.  For  fire-resistance  is  not  an  indefinite 
something  which  can  be  added  to  or  taken  from  a  building 
design  at  will,  as,  for  instance,  a  coat  of  fireproof  paint,  a  supply 
of  fire  buckets,  or  even  a  standpipe  and  hose  reels.  The  question 
goes  deeper  than  this,  for  the  vital  fire-resisting  qualities  must 

295 


296         FIRE    PREVENTION    AND    FIRE    PROTECTION 

be  inherent  in  the  design,  and  cared  for  as  naturally  as  are  the 
commercial  aspects. 

A  building  intended  to  resist  fire  may  be  likened  to  a  position 
intended  to  resist  attack.  The  works  to  be  defended  must 
first  be  well  chosen  as  to  position,  and  substantially  and  scientifi- 
cally designed;  second,  well  carried  out  in  all  details  at  crucial 
points;  and,  lastly,  manned  by  an  effective  garrison  or  force. 
"  Requirements  of  Design  and  Construction.  —  A  building, 
to  be  entirely  successful  from  the  standpoint  of  fire-resistance, 
must  include  something  more  than  simply  the  employment  of 
fire-resisting  materials  in  its  essential  design.  Each  building 
must  be  largely  a  problem  unto  itself, 'but,  in  general,  it  will  be 
found  that  adequate  and  entirely  successful  fire-resisting  con- 
struction will  result  if  the  following  general  requirements  are 
included. 

First:  A  careful  and  scientific  fire-resisting  plan  or  arrange- 
ment of  the  whole  structure,  with  due  consideration  given  to 
stability,  efficiency  and  permanency.  Without  this,  much 
attention  paid  to  purely  structural  questions,  detail  or  equip- 
ment, may  be  rendered  of  little  or  no  avail. 

Second:  Care  in  providing  adequate  and  fire-resisting  details 
to  make  efficient  the  general  plan  adopted.  These  considera- 
tions include  such  features  as  fire  doors,  fire  windows  elevator- 
and  stair-enclosures,  column  protections  and  partitions,  etc. 

Third:  Suitable  equipment  to  cope  with  either  interior  or 
exterior  fire,  such  as  sprinklers,  standpipes,  hose  reels,  thermo- 
stats, etc. 

General  Design.  —  The  first  requirement,  viz.,  a  carefully 
considered  general  arrangement  and  design  of  the  whole  structure 
with  a  view  to  providing  the  utmost  efficiency  as  well  as  perfect 
suitability,  seldom  gets  due  consideration,  for,  unfortunately, 
the  idea  has  been  and  still  is  much  too  prevalent  that  the  employ- 
ment of  non-combustible  or  fire-resisting  materials  for  the  main 
structural  members  is  all-sufficient  without  regard  for  plan  or 
arrangement,  details,  or,  in  fact,  any  other  considerations  what- 
soever. Many  a  building  erected  of  the  best  materials  has  been 
found  sadly  wanting  under  severe  fire  test  from  inherent  defects 
in  the  original  plan,  and,  likewise,  many  a  building  of  excellent 
plan  has  been  so  little  considered  in  the  matter  of  solidity  or 
thoroughness,  or  in  vital  details,  as  to  render  failure  under  fire 
test  inevitable.  But  without  a  proper  general  design  to  start 


PLANNING   AND   GENERAL   DESIGN  297 

with,  confusion,  danger  and  general  inefficiency  are  very  apt  to 
result,  and  many  otherwise  excellent  details  of  the  carrying  out 
of  the  plan  are  rendered  valueless. 

Problems  entering  into  the  general  design  will  include  the 
suitability  of  plan  and  construction  for  the  purposes  intended; 
the  isolation  'of  any  especially  dangerous  hazards;  the  subdivi- 
sion of  large  unobstructed  areas;  protection  against  dangerous 
adjacent  risks  by  means  of  blank  walls  or  adequately  protected 
openings;  provisions  for  light  and  air  without  introducing  in- 
terior open  shafts;  the  accessible  and  commodious  arrangement 
of  stairways  and  their  protection  against  fire  and  smoke,  or  the 
introduction  of  vertical  fire  walls;  the  suitable  location  of  eleva- 
tor shafts  so  as  to  render  them  capable  of  fire-resisting  construc- 
tion, as  well  as  convenient  and  serviceable;  and  the  general  scheme 
of  construction  which  will  adapt  itself  to  the  employment  of 
wholly  suitable  materials  to  be  used  in  the  right  way. 

Character  of  Building.  —  The  first  general  questions  whicli 
will  serve  largely  to  determine  a  fire-resisting  plan  are  the  uses 
to  which  the  building  is  to  be  put  and  the  nature  of  its  location. 
These  considerations  should  also  have  the  greatest  weight  in 
deciding  what  is  to  be  the  general  scheme  of  construction,  that 
is,  in  how  far  the  proposed  use  of  the  structure  should  tend  to 
emphasize  safety  to  occupants,  safety  to  contents,  or  both,  or 
principally  safety  to  the  structure  itself. 

If  the  building  is  to  be  used  as  a  hotel,  apartment  house,  school 
or  place  of  public  amusement  or  assembly,  manifestly  the  safety 
of  large  numbers  of  people  is  of  the  first  importance  and  the 
plan  should  always  be  subordinated  to  this  requirement.  The 
building  should  be  fire-resisting  to  protect  itself  and  those  within 
it  as  far  as  possible  from  fire  of  either  interior  or  exterior  source; 
fire-resisting  as  a  safeguard  to  neighboring  buildings  and  in- 
terests; and  fire-resisting  to  prove  of  positive  value  to  the  owners 
under  fire  test.  But  in  addition  to  all  these  demands,  reasonably 
to  be  expected  by  the  public  of  a  building  of  this  nature,  the 
safety  of  human  life  must  remain  of  the  first  importance,  and  the 
only  adequate  provision  lies  in  the  original  planning.  Fire, 
smoke  and  panic  must  all  be  provided  against,  and  proper  means 
of  egress  or  vertical  fire  walls  are  the  safeguards  which  will  make 
this  possible  in  the  original  plan.  Makeshift  alterations  at  some 
later  day,  after  the  community  has  been  aroused  over  some 
appalling  calamity,  may  not  serve  properly  to  correct  errors  of 


298         FIRE    PREVENTION    AND    FIRE    PROTECTION 

original  design,  and  the  renting  or  holding  value  of  the  property 
at  once  becomes  impaired. 

If,  on  the  other  hand,  the  building  is  to  be  used  as  a  storage 
warehouse,  then  the  first  thought  should  be  the  greatest  possible 
isolation  of  the  contents  from  outside  risks  of  any  nature,  and 
the  subdivision  of  large  areas  so  as  to  reduce  to  a  minimum  the 
danger  of  spontaneous  combustion  or  combustion  from  any 
interior  source. 

If  to  be  a  department  store,  or  a  large  commercial  emporium 
liable  to  contain  both  large  numbers  of  people  and  valuable 
stocks  of  goods,  then  both  safety  of  occupants  and  safety  of 
contents  must  be  provided  for.  Manifestly,  unprotected  mill 
construction  would  be  totally  inadequate  for  safety  of  either 
occupants  or  contents,  nor  would  such  means  of  egress  as  are 
usually  provided  in  an  office  building  be  sufficient,  owing  to  the 
inflammable  nature  of  the  contents. 

» If  the  structure  is  to  be  a  manufacturing  building,  attention 
must  be  given  to  the  hazards  inherent  in  that  particular  busi- 
ness and  provision  made  accordingly.  Dangerous  departments 
of  manufacture  involving  the  use  of  fire,  oils,  paints,  glue,  ex- 
plosives and  the  like,  should  be  carefully  isolated  in  the  plan  or 
cut  off  from  the  balance  of  the  structure,  where  possible,  by 
fire-resisting  walls,  or  be  given  added  means  of  fire  extinguish- 
ment. The  special  hazards  incident  to  the  various  operations 
in  all  usual  lines  of  manufacture  are  now  well  known,  and,  thanks 
to  the  statistics  gathered  by  insurance  interests,  and  particularly 
by  the  National  Fire  Protection  Association,  the  especially  dan- 
gerous features  of  all  factory  processes  may  be  indicated  with 
considerable  certainty.  For  such  data,  reference  should  be 
made  to  the  "  Quarterly  "  Bulletins  issued  by  the  National  Fire 
Protection  Association,*  in  which  the  "Special  Hazards"  of  a 
great  number  of  materials  and  processes  used  in  manufacturing 
are  given  at  length.  This  isolation  of  dangerous  features,  not 
in  separate  buildings,  but  on  separate  safeguarded  floors,  or  in 
adequately  cut-off  rooms,  also  serves  to  preserve  the  continuity 
of  manufacturing  operations  in  the  balance  of  the  plant,  even 
though  some  special  room  or  department  is  burned  out.  This  is 
an  important  consideration  in  all  manufacturing  businesses. 

For  office  buildings,  which  do  not  generally  constitute  a  very 
dangerous  risk,  the  plan  should  aim  to  confine  fire  to  the  unit  or 
*  See  also  page  313. 


PLANNING   AND    GENERAL   DESIGN  299 

apartment  within  which  it  originates.  The  considerable  number 
of  watchful  tenants,  the  usual  absence  of  any  particularly  dan- 
gerous contents,  and  the  prevalent  subdivision  into  small  units 
of  area,  all  serve  greatly  to  reduce  the  apparent  risk  attendant 
upon  the  congregation  of  so  many  people  within  large  buildings; 
but  the  smoke  and  panic  problems  are  still  a  decided  menace, 
and  the  effectual  carrying  out  of  the  plan  becomes  largely  a 
matter  of  adequate  detail,  as  will  be  touched  upon  later. 

These  may  all  seem  trite  observations,  but  did  the  architect 
of  the  Iroquois  Theater  properly  consider  the  quick  emptying 
of  that  auditorium,  especially  of  the  balconies,  in  time  of  danger? 
Did  the  owners  of  the  Granite  Building  in  Rochester  fully  appre- 
ciate the  dangers  incident  to  a  large  dry-goods  business,  that 
they  were  content  with  unprotected  means  of  communication 
between  their  building  and  the  adjoining  stores?  The  answers 
are  self-evident. 

Limitation  of  Occupancy.*  —  In  the  preceding  paragraph 
the  character  of  building  has  been  discussed  from  the  standpoint 
of  use  or  occupancy,  on  the  supposition  that  the  building  is 
designed  for  some  particular  tenantry,  and  that  it  is  used  for 
that  purpose  alone.  We  now  have  to  consider  those  cases,  by 
no  means  rare,  in  which  the  building  is  designed  for  one  purpose, 
but  where,  owing  to  change  in  rental,  or  owing  to  vague  classifi- 
cation in  the  first  place,  the  occupancy  is  quite  different  from 
that  contemplated  in  the  design. 

The  so-called  "loft  buildings"  in  New  York  City  are  a  case  in 
point.  As  the  name  implies,  this  type  of  building  was  originated 
and  designed  for  the  display  or  storage  of  goods,  that  is,  as 
storage  rooms,  sample  rooms,  or  display  rooms  for  manufactured 
goods  or  articles.  The  crusade  against  "sweat-shop"  methods, 
however,  quite  accidentally  brought  about  the  occupation  of 
some  of  the  earlier  "loft"  buildings  by  garment  makers,  etc., 
and  the  experiment  was  so  satisfactory  that  "loft"  buildings  in 
New  York  City  multiplied  rapidly.  Owing  to  certain  restric- 
tions in  the  construction  of  buildings  over  150  feet  high,  these 
structures  have  generally  been  built  ten  to  twelve  stories  in 
height.  Hence  the  anomalous  condition  exists  of  factory  occu- 
pancy in  ten-  and  twelve-story  buildings  designed  as  lofts  only 
—  in  other  words,  the  means  of  egress  and  the  character  of 
auxiliary  equipment  have  generally  been  designed  for  a  very 
*  See  also  paragraph  "Safety  of  Employees,"  Chapter  XXV. 


300         FIRE    PREVENTION    AND    FIRE    PROTECTION 

limited  tenantry,  and  for  a  moderate  fire  hazard,  while,  as  a 
matter  of  fact,  the  actual  tenantry  is  often  very  large  and  the 
manufacturing  hazard  great. 

The  conditions  in  the  Asch  Building,  described  in  Chapter  VI, 
are  only  typical  of  hundreds  of  buildings.  From  a  labor  census 
made  in  190&  it  appears  that  in  one  block  in  New  York  City 
there  were  no  less  than  77  loft  factories,  employing  4007  opera- 
tives, while  from  figures  compiled  about  January  1,  1911,  by  the 
Women's  Trade  Union  League,  it  was  estimated  that  the  average 
factory  worker  in  New  York  is  now  employed  seven  stories  above 
the  ground. 

Of  such  loft  buildings,  Mr.  H.  F.  J.  Porter,  the  well-known 
authority  on  fire  drills,  has  said:* 

I  have  had  some  fifty  odd  requests,  since  the  Asch  Build- 
ing disaster  in  this  city,  to  put  fire  drills  in  loft  buildings  in  this 
city.  I  am  compelled  to  state  that  such  a  drill  cannot  be  put 
in  a  single  loft  building.  In  other  words,  the  only  thing  left 
for  the  occupants  of  any  loft  building  in  this  city  in  case  of  fire 
is  what  has  always  been  left  to  them  as  alternatives,  either  to 
jump  to  death  or  to  burn  to  death. 

Limitation  of  occupancy  should,  therefore,  be  strictly  enforced 
by  the  owners  of  buildings,  —  limitation  as  to  number  of  tenants 
and  limitation  as  to  hazard  of  occupancy  —  so  as  always  to 
keep  the  number  of  tenants  and  the  hazard  of  occupancy  well 
within  the  limitations  of  the  building.  Rigid  enforcement  of 
such  limitation  should  also  be  insisted  on  by  municipal  regula- 
tions. (Indeed,  Mr.  Porter  goes  even  further,  and  advises  that 
a  satisfactory  rapid  egress  test  be  required  of  all  such  buildings 
before  being  accepted  for  occupancy.)  Nor  would  such  regula- 
tions be  at  all  unreasonable.  No  one  would  think  of  occupying 
an  ordinary  store  as  a  place  of  public  amusement  until  the  laws 
regarding  audiences,  etc.,  had  been  complied  with.  Why,  then, 
should  large  numbers  of  people  be  allowed  not  only  to  occupy 
poorly  designed  and  poorly  equipped  loft  buildings,  but  to  carry 
on  therein  distinctly  hazardous  processes  of  manufacture?  Such 
occupancy  is  distinctly  contrary,  in  every  way,  to  the  simplest 
rules  of  fire  protection. 

Means  of  Egress  comprise  interior  stairways  and  elevators, 
and  exterior  fire  escapes.  Escalators  are  also  sometimes  used 
in  department  stores  and  theaters. 

*  1911  Proceedings  of  National  Fire  Protection  Association,  page  152. 


PLANNING    AND    GENERAL   DESIGN  301 

Such  features  in  the  building  plan  or  design  must  be  con- 
sidered from  three  more  or  less  distinct  standpoints;  1,  ordinary 
service,  in  providing  access  to  and  egress  from  various  floors 
under  normal  conditions;  2,  emergency  service,  in  providing 
safe  and  rapid  means  of  egress  for  occupants  in  time  of  fire  or 
panic;  3,  emergency  access  for  firemen. 

1.  Ordinary  Service.  —  A  candid  inquiry  into  the  means  of 
egress  provided  in  ordinary  buildings,  even  including  many  fire- 
resisting  structures,   will  show  that  such  features  are  usually 
considered  from  this  standpoint  alone.     Both  stairway-  and  ele- 
vator-service are  designed  for  usual  conditions,  both  as  regards 
capacity  and  safety,  while  in  flagrant  examples,  even  normal 
conditions  are  not  properly  provided  for,  inasmuch  as  no  limi- 
tation   of   occupancy   has   been   enforced.     The   so-called   loft 
buildings  of  New  York  City,  described  in  the  preceding  para- 
graph, are  a  case  in  point,  wherein  even  normal  stair-  and  ele- 
vator-service is  often  taxed  to  unreasonable  limits,  while  efficient 
emergency  service  is  practically  impossible. 

2.  Emergency  Egress  is  of  paramount  importance  in  the  de- 
sign of  theaters   or  other  places   of  public   assembly,   hotels, 
schools,   department   stores,   or   manufacturing   buildings    conr 
taining  many  operatives. 

In  arriving  at  a  determination  of  the  means  of  egress  to  be 
provided  in  any  such  building  for  emergency  use,  no  allowance 
should  be  made  for  elevators,  as  the  amount  of  service  to  be 
absolutely  depended  on  in  time  of  need  is  problematical;  nor 
on  escalators,  as  such  mechanical  devices  are  too  subject  to 
break  down.  The  problem  of  emptying  a  building  within  a 
reasonable  time,  therefore,  resolves  itself  into  one  of  three  requi- 
sites; (a)  to  provide  suitable  stairways  and  fire  escapes  of  a 
capacity  and  arrangement  sufficient  to  care  for  the  maximum 
number  of  occupants;  or  (b)  to  enforce  limitation  as  to  occu- 
pancy so  as  not  to  exceed  the  capacity  of  the  stairways  pro- 
vided; or  (c)  to  subdivide  the  building  by  means  of  one  or  more 
vertical  fire  walls  extending  from  cellar  to  roof. 

Even  fire  drills,  as  described  in  Chapter  XXXVII,  are  not 
practicable  unless  one  of  these  alternatives  is  adopted.  No  less 
an  authority  than  Mr.  H.  F.  J.  Porter,  who  has  been  so  promi- 
nently associated  with  the  organization  of  fire  drills  in  manu- 
facturing plants,  etc.,  employing  large  numbers  of  operatives, 
has  stated  that  "the  studies  which  I  have  made  in  buildings 


302         FIRE    PREVENTION    AND    FIRE    PROTECTION 

regarding  the  capacity  of  exit  facilities  show  that  the  archi- 
tectural profession  has  apparently  been  working  absolutely  in 
the  dark,  and  has  produced  a  lot  of  buildings  unemptiable  in 
emergency."* 

As  a  remedy,  especially  in  manufacturing  buildings  and  the 
like,  Mr.  Porter  suggests  the  "  bi-sectional "  plan  of  building 
as  follows: 

When  we  analyze  the  situation  there  seem  to  be  three  ways 
of  solving  the  problem  of  escape  from  a  crowded  building: 

1.  Increase   the   number  of  stairways  in  a  building  so   as 
to  have  two  independent  stairways  leading  down  from  each 
floor  with  independent  exits  at  their  base;   in  a  ten-  or  twenty- 
or  more-story  building  this  would  be  impossible,  as  great  sections 
of  the  building  would  have  to  be  engrossed  by  stairways,  and 
stairways  are  where  the  congestion  occurs  which  causes  acci- 
dents. 

2.  Reduce    the    number  of    occupants  per    story  to    the 
capacity  of  the  stairways.     By  actual  test,  the  capacity  of  a 
stairway  wide  enough  for  two  people  to  go  down  abreast,  where 
the  distance  between  floors  is  from  ten  to  twelve  feet,  is  thirty 
people  per  story.     It  will  be  manifestly  impossible  to  limit  the 
number  of  people  per  story  in  this  way;   manufacturing  or  busi- 
ness must  be  run  in  accordance  with  other  requirements. 

3.  Eliminate    the    stairways    by  some    means    altogether 
from  consideration,  so  as  to  make  each  story,  for  purposes  of 
escape  from  danger,  practically  a  first-story  or  ground  floor; 
that  is,  enable  people  to  flow  out  horizontally  from  it.     This 
would  be  the  ideal  way,  if  it  could  be  done;   and  as  it  has  been 
done  frequently,  it  can  be  done  again,  and  the  means  should 
become  generally  known  and  adopted  as  standard  practice. 

The  method  to  accomplish  this  result  is  a  fire  wall  so 
arranged  in  a  building  as  practically  to  bisect  it.  (See  Fig.  46.) 
This  wall  must  be  continuous  from  cellar  to  roof,  and  be  pro- 
vided with  doorways  on  each  floor  closed  by  automatic  fire 
doors.  The  building  must  be  designed  with  two  sets  of  egress 
facilities  of  ample  proportions,  one  set  located  on  each  side  of 
the  wall  accessible  from  each  floor.  No  fire  is  at  all  likely  to 
occur  on  both  sides  of  this  fire  wall  simultaneously,  unless  it  is 
of  incendiary  origin.  Should  a  fire  occur,  the  alarm  sounds 
and  the  occupants  of  the  building  on  the  side  of  the  wall  where 
the  fire  is  merely  have  to  pass  through  the  doorways  in  the  fire 
wall,  close  the  doors  after  them,  and  be  perfectly  safe.  .  A  fire 
drill  will  empty  either  side  of  a  building  so  equipped,  no  matter 
how  many  stories  high,  in  a  minute.  The  refugees  may  re- 
main in  the  safe  side  of  the  building  until  the  fire  fighters  have 
put  out  the  fire,  or  they  may  at  any  time  use  the  egress  facili- 
ties provided  there,  which  would  be  free  from  smoke  or  fire. 

*  Compare  with  page  509. 


PLANNING  AND   GENERAL   DESIGN 


303 


The  fire  wall  in  a  factory  building  thus  provides  a  safe  retreat 
from  danger  similar  to  the  cyclone  cellar  of  the  western  house 
or  the  collision  bulkhead  of  the  ocean  steamer. 


Fire  Door  - 


Fire  Door« 


-100' — 


FIG.  46.  —  "Bi-sectional"  Plan  of  Typical  Loft  Building. 

The  fire  wall  enhances  the  utility  of  all  forms  of  exit. 
For  example,  the  outside  iron  fire  escape  has  been  shown  to  be 
a  very  unsafe  means  of  effecting  egress  from  a  burning  building. 
In  the  Asch  Building  fire  the  fire  escape  was  totally  destroyed 
by  the  flames,  and  people  who  tried  to  use  it  were  burned  up 
on  it.  The  fire  wall  largely  eliminates  the  necessity  for  the 
use  of  the  fire  escape  on  this  type  of  building,  but  if  retained 
the  fire  escapes  on  the  safe  side  of  the  fire  wall  would  be  free 
from  fire  danger.* 

As  regards  stair  capacity  for  emergency  egress,  see  also  para- 
graph ''Capacity  of  Stairs/7  Chapter  XV,  and  for  egress  in 
theaters  and  like  places  of  public  assembly,  see  Chapter  XXII, 
particularly  paragraphs  " Exits"  and  " Quick  Emptying  Tests." 

Emergency  Access.  —  Security  in  stairways  may  not  only 
prove  of  inestimable  value  to  the  occupants  of  the  structure,  but 
possibly  to  the  owner  as  well,  for  there  is  then  provided  something 
far  better  than  ladders  or  water  towers  for  the  use  of  firemen. 
If  these  men,  who  have  a  hazardous  calling  at  the  best,  can  be 
assured  that  stair  wells  are  secure  and  isolated,  they  will  at  once 
take  advantage  of  this  most  efficient  means  of  attacking  and 

*  See  The  Survey,  July  15,  1911. 


304         FIRE    PREVENTION    AND    FIRE    PROTECTION 

fighting  fire  from  within,  rather  than  from  without.  As  firemen 
have  often  explained  to  the  writer,  the  trouble  now  is  that 
adequate  isolation  is  seldom  provided,  and,  in  severe  fires,  the 
construction  is  almost  invariably  such  that  danger  constantly 
exists  either  of  being  cut  off  below  or  of  seeing  the  supporting 
treads  and  landings  crack  or  give  way. 

In  the  comparatively  insignificant  fire  in  the  Vanderbilt  Build- 
ing in  New  York,  the  crooked  stairway,  surrounding  the  elevator 
shaft,  was  so  filled  with  smoke  that  the  firemen  were  overcome  in 
several  instances  while  attempting  to  carry  hose  to  the  upper 
floors,  although  flame  failed  to  touch  this  portion  of  the  build- 
ing. Also,  in  the  Parker  Building  fire  the  stairways  were 
wholly  inadequate  in  both  number  and  size,  and,  what  was  of 
vital  importance  in  the  early  stages  of  fighting  the  fire,  they 
were  more  of  a  menace  than  aid  to  the  firemen. 

Stairways  and  Fire  Escapes  are  considered  in  detail  as  to 
location,  design  and  construction  in  Chapter  XV. 

Location  and  Exposure  Hazard.  —  The  location  of  the  site 
is  important  as  affecting  a  fire-resisting  plan.  If  the  proposed 
structure  is  wholly  or  largely  isolated,  no  great  care  is  necessary 
to  provide  against  exterior  hazard,  and  the  plan,  precautions 
and  materials  even,  may  be  modified  accordingly.  But  if  lo- 
cated in  the  midst  of  dangerous  risks,  the  utmost  possible  pro- 
tection must  be  given  to  all  sides;  if  adjoining  an  especially 
dangerous  neighbor  on  the  side  or  rear,  then  the  plan  should 
properly  provide  for  protection  in  that  direction,,  either  by 
means  of  blank  brick  walls  or  by  minimum  window  areas  pro- 
vided with  fire  shutters  or  at  least  with  fire-resisting  frames  and 
sash.  If  located  on  a  narrow  street  or  alley,  where  the  burning 
of  an  opposite  or  nearby  non-fire-resisting  structure  would 
surely  mean  severe  exposure,  then  the  character  of  the  exposed 
wall,  the  protection  of  window  openings,  and  the  desirability 
of  providing  "open  sprinklers"  at  the  roof  line  or  at  the  window 
heads  must  all  be  considered. 

The  report  of  the  National  Fire  Prevention  Association  Com- 
mittee on  the  Baltimore  conflagration  contains  the  following: 

From  a  fire  protection  viewpoint  it  is  essential  that  solid 
brick  walls  without  openings  of  any  kind  should  be  provided 
wherever  possible.  Where  windows  or  other  openings  are  nec- 
essary they  should  be  few  in  number  and  of  small  area.  They 
should  also  be  protected  with  the  best-known  devices  for  the 
protection  of  such  openings  against  fire. 


PLANNING   AND    GENERAL   DESIGN  305 

The  protection  of  window  openings,  etc.,  is  a  detail  of  con- 
struction to  be  considered  later  in  the  design  (see  Chapter  XIV), 
but  the  number  and  locations  of  windows  or  other  openings  are 
matters  to  determine  in  the  original  plan. 

Regarding  the  location  and  site  of  public  assembly  buildings, 
such  as  theaters,  etc.,  see  Chapter  XXII. 

Subdivision  of  Large  Areas.  —  Aside  from  the  question  of 
egress,  large  horizontal  floor  areas  in  buildings  should  be  sub- 
divided by  means  of  fire-resisting  walls  or  partitions  into  units 
of  moderate  size,  for  three  principal  reasons. 

First:  To  localize  or  confine  internal  fire,  so  that  it  need  not 
spread  beyond  the  unit  of  area  in  which  it  originates,  thus 
effectively  limiting  the  fire  damage  and  consequent  financial  loss. 

Second:  To  minimize  the  damage  resulting  from  severe  expo- 
sure or  conflagration  conditions,  by  breaking  up  large  undivided 
floor  areas  into  efficiently  surrounded  units. 

Third:  To  aid  fire-department  work  in  the  extinguishment 
of  fire. 

1.  Numerous  fires  in  office  buildings,  hotels,  warehouses  and 
the  like  have  proved  that  fire  may  originate  within  a  room  or 
compartment  which  is  surrounded  by  an  efficient  partition,  com- 
pletely consume  the  combustible  trim  and  contents,  and  remain 
undiscovered  until  hours  afterward. 

If  thoroughly  fire-resisting,  such  division  walls  or  partitions 
not  only  confine  the  fire  damage  to  a  small  area,  but  they  serve, 
as  well,  to  augment  the  fire-resisting  qualities  of  the  whole 
structure.  If  only  partially  fire-resisting,  dividing  partitions 
are  still  of  great  value  in  breaking  up  strong  draughts,  and  in 
providing  barriers  behind  which  the  fire  department  may  make 
a  successful  stand. 

The  possibility  of  the  subdivision  of  large  horizontal  areas  in 
buildings  depends  largely  upon  the  uses  to  which  the  structure 
is  to  be  put,  but  here,  as  in  many  other  points  connected  with 
fire-resisting  design,  the  ideas  of  the  fire  protectionist  or  the 
interests  of  insurance  companies  are  found  to  be  very  different 
from  the  demands  of  owner  or  occupant. 

For  modern  office  buildings,  no  limitations  as  to  areas  need 
be  prescribed,  as  such  buildings  usually  are,  of  necessity,  sub- 
divided by  supposedly  fire-resisting  partitions  into  relatively 
small  offices.  This  is  also  largely  true  of  hotels  and  apartment 
houses,  except  that,  in  all  of  these  classes  of  buildings,  especial 


306       FIRE    PREVENTION    AND    FIRE    PROTECTION 

care  is  necessary  to  surround  stairways  and  elevator  shafts  by 
approved  fire-resisting  partitions,  not  only  on  account  of  the 
fire  hazard,  but  to  prevent  panic  and  the  smoke  hazard  as  well. 

In  retail  and  wholesale  stores,  warehouses  and  factory  build- 
ings, large  undivided  areas  are  very  apt  to  be  considered  indis- 
pensable —  in  store  buildings  because  the  impression  on  the 
customer  of  vastness  and  business  magnitude  is  supposed  to  be 
in  direct  proportion  to  the  unobstructed  area,  and  in  warehouses 
and  manufacturing  buildings  because  the  arrangement  of  ma- 
chinery or  the  handling  of  goods  are  considered  of  more  impor- 
tance than  dividing  fire  walls.  In  such  instances  the  interests 
of  the  lessees  are  almost  always  contrary  to  the  interests  of  the 
owners  or  underwriters. 

The  expediency  of  allowing  large  undivided  areas  in  department 
stores,  under  stringent  regulations  as  to  sprinklers,  fire  doors, 
stairways,  etc.,  instead  of  insisting  upon  areas  of  not  over  10,000 
square  feet  (as  has  been  done  in  special  instances  in  Boston)  is 
debatable,  to  say  the  least,  but  the  question  of  undivided  floor 
areas  is  of  much  less  importance  when  the  risk  is  provided  with 
automatic  sprinklers. 

In  warehouse  or  factory  construction,  where  large  undivided 
areas  are  often  thought  necessary  (and  commonly  filled  with 
large  quantities  of  highly  inflammable  merchandise  and  oily 
machinery  and  floors),  it  is  very  doubtful  if  any  great  interfer- 
ence to  business  interests  would  result  from  municipal  regula- 
tions which  would  prohibit,  under  any  conditions,  undivided 
floor  areas  in  excess  of  10,000  square  feet.  If  larger  areas  than 
this  were  required  to  be  divided  from  the  ground  up  by  solid 
masonry  partitions,  the  fire  departments  could  then  hold  fires 
in  better  check,  and  make  conflagrations  impossible. 

In  large  open  structures,  such  as  car  barns,  pier  sheds,  ferry 
terminals,  churches,  armories  and  even  theaters,  division  walls 
or  fire  stops  to  limit  moderately  the  horizontal  areas  are  usually 
considered  impracticable.  The  usual  result  of  fire  in  such 
structures  is,  therefore,  the  complete  destruction  of  the  building 
and  contents,  due,  principally,  to  the  absence  of  division  walls. 
In  buildings  of  this  type,  it  is  the  usual  experience  of  fire  depart- 
ments that,  if  fire  is  not  extinguished  in  an  incipient  stage,  great 
headway  is  soon  acquired,  and  the  total  resources  of  the  depart- 
ment cannot  prevent  the  ultimate  consumption  of  all  combus- 
tible contents,  if  not  the  collapse  of  the  structure.  The  primary 


PLANNING   AND    GENERAL    DESIGN  307 

reason  for  this  is  the  great  difficulty  experienced  in  getting  hose 
streams  to  bear  upon  the  seat  of  the  fire  before  it  has  spread 
beyond  control. 

The  introduction  of  fire  walls  in  some  classes  of  structures  is 
admittedly  a  vexing  problem,  but  much  can  be  done  if  the 
matter  is  well  studied  in  connection  with  the  original  planning. 
In  hollow  buildings,  such  as  churches,  theaters,  and  armories, 
etc.,  the  use  of  the  building  naturally  prohibits  division  walls, 
thereby  necessarily  increasing  the  fire  hazard.  But  even  in 
such  structures,  much  can  be  done  to  improve  the  qualities  of 
fire-resistance.  This  is  done  in  theaters  by  cutting  off  the  stage 
from  the  auditorium,  and  a  similar  isolation  of  the  foyer  from 
the  auditorium  could  usually  be  affected.  Churches  and  armor- 
ies could  usually  be  designed  in  a  similar  manner.  Structures 
such  as  piers,  ferry  terminals,  car  barns,  etc.,  where  the  sub- 
division of  horizontal  areas  only  has  to  be  considered,  present 
no  great  difficulty  as  to  fire-stops.  In  fact,  the  ordinary  plan 
of  such  buildings  should  lend  itself  readily  to  division  and 
subdivision. 

The  Universal  Mercantile  Schedule  for  a  " standard  building" 
allows  2500  square  feet  floor  area  as  a  basis  from  which  area 
charges  are  figured.  The  rating  of  area  for  a  fire-resisting 
building,  as  used  by  the  Boston  Board  of  Fire  Underwriters,  is 
given  in  Chapter  III,  page  45. 

2.  The  subdivision  of  floor  areas  will  largely  serve  to  prevent 
strong  draughts  of  air  from  one  side  or  portion  of  a  building  to 
another  side  or  portion,  thereby  greatly  avoiding  the  hazardous 
conditions  of  severe  exposure  fire  or  wide-spread  conflagration. 
It  was  found  in  both  the  Baltimore  and  San  Francisco  confla- 
grations that  fire  not  only  swept  through  undivided  floors  with 
greater  rapidity  than  in  divided  areas  (as  would  naturally  be 
expected),  but  with  greater  intensity  as  well.  In  other  words, 
each  horizontal  story  becomes  a  flue,  the  length  of  which  is  the 
distance  from  the  window  openings  lying  nearest  the  exposure 
to  those  in  the  opposite  wall. 

The  following  conclusion  bearing  upon  this  point  is  taken 
from  the  report  of  the  National  Fire  Protection  Association  upon 
the  Baltimore  conflagration: 

Large  unbroken  floor  areas  assist  the  spread  of  fire  and 
serve  to  augment  its  severity.  Buildings  of  considerable  area 
and  having  large  quantities  of  combustible  contents  should  be 


308         FIRE    PREVENTION   AND    FIRE    PROTECTION 

subdivided  by  substantial  brick  fire  walls  sufficient  to  form  a 
positive  barrier  to  the  spread  of  fire. 

The  large  areas  now  so  common,  and  particularly  in  those 
buildings  having  unenclosed  vertical  openings,  undoubtedly 
furnish  conditions  which  render  even  the  most  approved  meth- 
ods of  fire-resistive  construction  now  in  use  of  doubtful  value. 

It  was  noticeable,  even  in  office  buildings,  that  the  damage 
was  generally  greatest  where  there  were  large  offices  without 
any  sub-dividing  partitions. 

3.  It  has  been  pointed  out  that  the  volume  and  intensity  of 
fire,  and  the  rapidity  with  which  it  will  gain  headway,  are  all 
vastly  greater  in  large  areas  than  in  small  ones.  It  is  also  a 
much  more  difficult  matter  for  a  fire  department  effectively  to 
surround  and  fight  a  fire  of  large  area.  Much  valuable  time  is 
lost  in  running  long  lines  of  hose,  in  addition  to  which,  smoke 
conditions  are  often  so  bad  that  the  actual  location  of  the  fire 
cannot  either  be  found,  or  reached  if  found.  There  is  a  limit 
to  the  ability  of  firemen  to  inhale  smoke  or  withstand  heat,  and 
once  this  limit  is  reached,  the  offensive  operations  of  extinction 
cease,  the  firemen  are  put  on  the  defensive,  and  the  fire  is  master 
of  the  situation.  These  considerations  would  point  to  the  de- 
sirability of  fixing  what  might  be  termed  the  maximum  area 
which  can  be  efficiently  handled  by  a  city  fire  department.  "  As 
a  working  unit,  5000  square  feet  has  been  suggested,  with  a  limit 
of  100  feet  in  any  direction  (or  a  rectangle  50  by  100),  which  is 
as  large  an  undivided  area  as  the  experience  of  the  New  York 
Fire  Department  indicates  to  be  within  the  capacities  of  effec- 
tive fire  department  operations."* 

As  all  limitations  of  areas,  whether  required  by  municipal 
ordinances,  or  limited  by  insurance  interests,  or  adopted  as  a 
matter  of  expediency,  are  primarily  a  question  of  original  design 
and  planning,  it  is  important  to  plan  the  structure  wisely  from 
the  beginning.  The  subdivisions  should  be  made  either  by  solid 
brick  walls,  which  are  much  to  be  preferred,  or  by  other  approved 
and  substantial  fire-resisting  partitions.  All  openings  connecting 
such  areas  should  be  provided  with  approved  fire  doors  where 
possible,  but  even  partially  fire-resisting  doors,  if  closed,  are  not 
to  be  underestimated  in  preventing  the  rapid  spread  of  fire. 

Limit  of  Areas,  National  Board  Building  Code.  —  The  follow- 
ing tabulation  gives  the  limit  of  areas  to  be  enclosed  within 
brick  fire  walls,  as  recommended  in  the  Building  Code  of  the 
National  Board  of  Fire  Underwriters: 

*  See  Journal  of  Fire,  July,  1906,  page  8. 


PLANNING   AND    GENERAL   DESIGN 


309 


N on- fire-resisting  Construction. 

Any  occupancy,  height  limited  to  55 
feet. 

Area,  without  automatic-sprinkler  pro- 
tection. 
Fronting   on   one   street 

only 5,000  sq.  ft. 

Fronting  on  two  streets, 

that  is,    extending 

through  from  street  to 

street 6,000-sq.  ft. 

Corner    building,    front- 
ing on  two  streets  ....       6,000  sq.  ft. 
Fronting  on  three  streets      7,500  sq.  ft. 


N  on- fire-resisting  Construction. 

Any  occupancy,  height  limited  to  55 
feet. 

Area,  with   automatic-sprinkler  pro- 
tection (being  an  increase  of  50  per  cent, 
over  the  unsprinkled  area). 
One  street  front 7,500  sq.  ft 


Two  street  fronts 9,000  sq.  ft. 

Corner  building,  two 

street  fronts 9,000  sq.  ft. 

Three  street  fronts 11,250  sq.  ft. 


Fire-resisting  Construction. 

Occupancy,  stores,  warehouses  and 
factories.  Height  when  not  exceeding 
55  feet. 

Area,  without  automatic-sprinkler  pro- 
tection. 
Fronting   on   one   street 

only 10,000  sq.ft. 

Fronting  on  two  streets, 

that   is,   e  x  t  e  n  d  i  ng 

through  from  street  to 

street 12,000  sq.  ft. 

Corner  building,  fronting 

on  two  streets 12,000  sq.  ft. 

Fronting  on  three  streets    15,000  sq.  ft. 


Fire-resisting  Construction. 

Occupancy,  stores,  warehouses  and 
factories.  Height  when  not  exceeding 
55  feet. 

Area,   with  automatic-sprinkler  pro- 
tection  (being  an  increase   of  883   per 
cent,  over  the  unsprinkled  area). 
One  street  front 13,333  sq.  ft. 


Two  street  fronts 16,000  sq.  ft. 

C  o  r  n  er    building,    two 

street  fronts 16,000  sq.  ft. 

Three  street  fronts 20,000  sq.  ft. 


Fire-resisting  Construction. 

Occupancy,   stores,    warehouses  and 
factories.     Height  limited  to  100  feet. 

Area,  without  automatic-sprinkler  pro- 
tection, same  as  for  non-fireproof  con- 
struction. 
Fronting    on   one   street 

only 5,000  sq.ft. 

Fronting  on  two  streets, 

that   is,   extending 

through  from  street  to 

street 6,000  sq.  ft. 

Corner  building,  fronting 

on  two  streets 6,fOO  sq.  ft. 

Fronting  on  three  streets      7,500  sq.  ft. 


Fire-resisting  Construction . 

Occupancy,  stores,  warehouses  and 
factories.  Height  limited  to  100  feet. 

Area,  with  automatic-sprinkler  pro- 
tection (being  an  increase  of  33^  per 
cent,  over  the  unsprinkled  area). 


One  street  front 


3  sq.ft. 


Two  street  fronts 8,000  sq.  ft. 

Corner  building,  two 

street  fronts 8,000  sq.  ft. 

Three  street  fronts 10,000  sq.  ft. 


Fire-resisting  Construction. 

Occupancy,  other  than  stores,  ware- 
houses and  factories.  Height  limited 
to  125  feet. 

Area,  without  automatic-sprinkler  pro- 
tection, same  as  for  fireproof  construc- 
tion  limited   to  55   feet   and  with  au- 
tomatic-sprinkler protection. 
Fronting   on   one    street 

only 13,333  sq.  ft. 

Fronting  on  two  streets, 

that   is,   extending 

through  from  street  to 

street 16,000  sq.  ft. 

Corner  building,  fronting 

on  two  streets 16,000  sq.  ft. 

Fronting  on  three  streets.  20,000  sq.  ft. 


Fire-resisting  Construction. 

Occupancy,  other  than  stores,  ware- 
houses and  factories.  Height  limited 
to  125  feet. 

Area,  with  automatic-sprinkler  pro- 
tection (being  an  increase  of  50  per  cent, 
over  the  unsprinkled  area). 


One  street  front 20,000  sq.  ft. 


Two  street  fronts 24,000  sq.  ft. 

Corner    building,    two 

street  fronts 24,000  sq.  ft. 

Three  street  fronts 30,000  sq.  ft. 


310         FIRE    PREVENTION   AND    FIRE    PROTECTION 

Light- shafts  and  Interior  Courts.  —  But  if  large  undivided 
horizontal  areas  are  bad  from  the  view-point  of  fire-resistance, 
the  open  light-shaft  or  interior  court  is  far  worse.  For  this 
element  of  design  in  a  building  intended  to  be  fire-resisting  in 
any  sense  of  the  word,  or  in  fact  in  any  building  where  safety 
of  either  life  or  property  is  to  be  considered,  there  can  be  no 
justification  whatever.  The  risk  of  undivided  areas  then  be- 
comes tenfold,  for  in  place  of  undivided  horizontal  areas  only, 
we  have  undivided  vertical  areas,  than  which  no  feature  of 
building  design  presents  a  more  positive  possibility  of  ruin  and 
disaster. 

The  open  light-well  or  interior  roofed-over  court  is  simply  a 
more  architectural  treatment  of  the  old  method  employed  for 
obtaining  additional  light  over  large  interior  floor  areas.  Some 
of  the  old-time  mercantile  or  warehouse  buildings  may  still  be 
found  where  the  successive  floors  beneath  a  roof  skylight  are 
pierced  by  openings  to  admit  light  to  the  interior  areas  of  lower 
stories,  the  fancied  protection  against  draught  and  fire  commu- 
nication being  secured  through  the  use  of  wooden  trap  doors, 
hinged  at  the  sides,  which  are  supposed  to  be  closed  at  night. 

With  the  erection  of  more  extensive  and  more  architectural 
business  and  even  public  buildings,  it  was  soon  found  that  the 
interior  light-court  provided  not  only  a  means  of  lighting  interior 
areas,  but  that  this  feature  could  be  used  to  great  architectural 
advantage,  thus  providing  an  opportunity  for  the  display  of 
ornamentation,  and,  what  was  of  even  more  importance  to  the 
owner  or  tenant,  giving  the  impression  of  a  large,  attractive  and 
apparently  extensive  interior.  Hence  this  feature  of  design  has 
been  prominent  in  past  examples  of  hotels,  —  witness  the  Palace 
Hotel  in  San  Francisco  —  in  office  buildings,  —  witness  the 
Masonic  Temple  and  Chamber  of  Commerce  Buildings,  Chicago 
—  and  in  retail  and  department  stores  innumerable,  where, 
especially  at  the  holiday  season,  it  is  no  unusual  thing  to  see 
such  courts  decorated  with  festoons  of  evergreens,  light  paper 
ornaments,  rugs  and  draperies,  the  whole  possibly  illuminated 
with  strings  of  incandescent  lamps.  What  the  result  would  be 
in  case  of  fire,  in  a  store  thus  crowded  with  holiday  shoppers,  is 
easy  to  imagine  as  far  as  the  structure  and  its  stock  in  hand  is 
concerned,  and  frightful  to  contemplate  as  to  the  patrons. 

But,  owing  to  many  bitter  experiences  of  the  past,  it  is  now 
recognized  that  such  courts,  beautiful  and  imposing  as  they 


PLANNING   AND    GENERAL   DESIGN  311 

often  may  be,  are  nevertheless  even  more  dangerous  than  large 
undivided  horizontal  areas.  Great  fire  losses,  and  suffocation  by 
smoke  and  panic  are  the  almost  inevitable  consequences,  and  if 
fire-resistance  is  to  be  considered  at  all,  the  open  light-well  will 
soon  be  relegated  to  the  oblivion  which  it  deserves.  The  Home 
Store  Building  fire  in  Pittsburgh,  described  in  Chapter  VI,  was 
a  typical  example  of  the  wide-spread  ruin  resulting  from  the 
interior  open  court  running  from  basement  to  roof. 

Again  it  is  a  question  of  original  design. 

If  the  floor  area  is  so  large  that  adequate  lighting  cannot  be 
secured  by  means  of  the  windows  in  the  bounding  walls,  then 
the  only  alternative  is  either  to  indent  open  light-courts  from  the 
lot  lines,  or  else  to  provide  an  interior  light-well  wholly  within 
the  plan,  to  be  open  to  the  weather  in  either  case,  and  enclosed 
at  all  floors  by  means  of  adequate  fire-resisting  walls.  If  not  too 
limited  in  area,  or  if  not  situated  within  a  particularly  hazardous 
risk  (in  which  case  " auto-exposure,"  or  the  possible  communi- 
cation of  fire  from  floor  to  floor  through  the  window  openings 
must  not  be  overlooked),  such  courts  or  light-wells  could  still 
be  made  of  very  attractive  appearance,  and  susceptible  of  con- 
siderable architectural  treatment.  Light  and  pleasing  designs, 
combining  ornamental  metal  work  and  glass,  would  still  give 
adequate  views  across  and  up  and  down  the  well,  thus  preserving 
the  idea  or  impression  of  extent,  completeness,  or  architectural 
effect.  Prisms,  wire  glass  or  electroglazed  lights  —  all  recog- 
nized as  efficient  fire-retardants  —  would  be  readily  adaptable 
to  such  construction.  Something  similar  to  this  idea  may  be 
seen  in  the  treatment  of  the  interior  court  of  a  certain  large  retail 
dry-goods  store  in  Berlin,  Germany.  The  architectural  style 
was  "L'Art  Nouveau,"  and  the  court  in  question  was  open  to  the 
weather  above  (possibly  partly  covered  by  a  temporary  glass 
roof  during  severe  winter  weather)  and  filled,  on  the  ground- 
floor  level,  with  a  bright  and  attractive  flower  garden  containing 
a  fountain,  paths,  flower  beds,  seats,  etc.  Rising  from  the 
garden,  the  main  court  walls  were  built  of  light  stone  or  terra- 
cotta piers,  arched  openings,  etc.,  with  balustrades  at  each  floor 
level  between  the  piers,  behind  which  were  open  loggias  or  covered 
balconies,  cut  off  from  the  main-floor  areas  by  means  of  highly 
fantastic  partitions  or  screens,  designed  in  metal  work  and  glass, 
after  the  fashion  of  L'Art  Nouveau.  The  result  was  certainly 
most  pleasing  and  effective,  even  though  not  so  efficient  against 


312         FIRE   PREVENTION   AND   FIRE   PROTECTION 

fire  hazard  as  if  the  court  walls  had  been  of  brick  with  the  usual 
glass  areas. 

Vertical  Openings.  —  Much  that  has  previously  been  said 
regarding  open  light-shafts  is  also  distinctly  applicable  to  stair- 
and  elevator-shafts.  From  the  standpoint  of  fire-resistance, 
unprotected  stairways  and  elevators  are  wholly  wrong  and 
entirely  inconsistent  with  other  features  of  design  which  are  pro- 
vided with  great  care.  Thus,  for  instance,  we  insist  upon  fire- 
resisting  floor  construction,  not  only  to  carry  the  superimposed 
loads  safely  (for  ordinary  construction  would  do  that)  but  to 
provide  a  floor  system  which  will  prevent  the  communication 
of  fire  from  story  to  story,  and  which  will,  under  fire  test,  require 
a  minimum  of  repair.  And  then,  having  done  so,  we  promptly 
render  all  this  expense  of  no  avail  by  introducing  passages  of 
vertical  communication,  thus  inviting  wreck  and  ruin  from  fire 
and  water,  and  the  danger  of  panic  from  flame  or  smoke.  In- 
deed, the  entire  Baltimore  conflagration  was  undoubtedly 
attributable  to  this  most  common  but  deplorable  practice,  as  is 
shown  in  the  following: 

Near  the  center  of  the  building  (the  Hurst  dry-goods  store 
where  the  fire  originated)  was  an  unenclosed  well-hole  about 
14  feet  square  from  basement  to  sixth  story,  containing  a  stair- 
way and  passenger  elevator.  .  .  .  The  most  plausible  theory  is 
that  the  smoke  and  gases  from  a  smoldering  fire  ascended  the 
central  opening,  accumulated  in  the  upper  portion  of  the  build- 
ing, and  were  finally  exploded  when  reached  by  the  flames.  .  .  . 
The  Baltimore  conflagration  is  directly  chargeable  to  unpro- 
tected floor  openings.  Had  the  stair-  and  elevator-openings  in 
the  building  where  the  fire  originated  been  properly  protected, 
there  is  every  reason  to  believe  that  the  fire  department  would 
have  been  able  to  control  the  fire  at  the  start.* 

This,  and  other  experiences  in  the  Baltimore  conflagration 
and  in  other  fires,  led  the  committee  of  the  National  Fire  Pro- 
tection Association  which  investigated  the  Baltimore  fire  to 
recommend  as  follows  in  their  conclusions: 

Vertical  openings  throughout  buildings,  as  for  stairs  and 
elevators,  rapidly  communicate  fire  to  all  stories.  With  build- 
ings of  considerable  height  or  combustible  contents  this  is 
likely  to  result  in  fire  conditions  beyond  fire  department  control. 
All  such  floor  openings  should  be  enclosed  in  brick-walled  shafts, 
crowned  by  a  thin  glass  skylight,  and  extended  through  roof, 
with  fire  doors  at  openings  to  stories.  Unenclosed  vertical 

*  Report  of  National  Fire  Protection  Association. 


PLANNING   AND   GENERAL   DESIGN  313 

openings  are  considered  to  be  a  most  prominent  feature  con- 
tributing to  the  fire-cost  and  loss  of  life.  Neglect  to  guard  these 
openings  is  common  throughout  the  country.  Steps  should 
be  taken  to  rectify  this  condition  in  all  existing  buildings,  as 
well  as  in  those  hereafter  erected,  particularly  buildings  of 
mercantile,  manufacturing  and  storage  occupancy.  Municipal 
building  laws  and  insurance  discrimination  should  be  evoked 
to  this  end. 

That  the  importance  of  this  question  is  beginning  to  be  appre- 
ciated, is  evidenced  by  decided  improvements  in  recent  years 
in  both  building  codes  and  advanced  practice.  Thus  stairs 
and  elevators  are  increasingly  being  surrounded  by  fire-resisting 
enclosures,  whether  of  wire  glass  in  combination  with  ornamental 
frameworks  of  iron  or  bronze,  as  in  hotels,  apartments,  stores 
and  office  buildings,  or  of  brick,  concrete  or  tile  walls  with 
fire  doors,  as  in  more  dangerous  risks,  involving  the  hazard  of 
manufacture  or  the  storage  of  large  quantities  of  combustible 
goods.  But  of  whatever  materials  such  enclosures  may  be 
built,  the  question  comes  back  to  original  planning.  For  the 
problem  of  vertical  openings  involves  suitable  location  to 
provide  for  safety  and  convenience,  the  lighting  of  the  well- 
rooms  themselves  —  and  often  the  necessity  of  transmitting 
light  through  the  enclosures,  —  arid  all  of  these  points,  as  well 
as  fire-resistance,  must  be  duly  considered  in  the  original  design. 

The  design  and  construction  of  stairways  and  their  enclosures 
are  more  fully  considered  in  Chapter  XV,  while  elevator  shafts 
and  other  similar  vertical  openings  and  their  enclosures  are 
considered  in  Chapter  XVI. 

Isolation  of  Mechanical  Plants  and  Special  Hazards.  — 
The  isolation  of  mechanical  plants  and  any  or  all  other  fire 
hazards  within  a  building  are  also  features  of  planning  to  be 
considered.  This  is  generally  a  well-observed  rule  as  regards 
boiler  and  engine  rooms,  due  to  municipal  building  regulations 
which  usually  require  such  plants  to  be  enclosed  within  brick 
fire  walls  and  covered  by  only  thoroughly  fire-resisting  floors. 

The  design  of  storage  buildings  of  certain  types,  and  manu- 
facturing buildings  of  certain  processes,  also  requires  especial 
care  in  planning,  incident  to  the  special  hazards  involved.  Thus 
cotton  storehouses,  grain  elevators,  etc.,  and  bleach-,  dye-  and 
print-works,  breweries,  cordage  works,  cotton  mills,  flour  mills, 
glass  works,  packing  houses,  paper  mills,  pulp  mills,  rubber 
factories,  shoe  manufactories,  sugar  refineries,  tanneries,  woolen 


314         FIRE    PREVENTION    AND    FIRE    PROTECTION 

mills  and  many  other  lines  of  manufacturing  plants,  all  require 
intimate  knowledge  of  the  special  hazards  involved.  A  wide 
range  of  such  " Special  Hazards"  has  been  published  by  the 
National  Fire  Protection  Association  in  their  "  Quarterly  "  Bulle- 
tins, copies  of  which,  covering  almost  any  ordinary  process  of 
manufacture  or  condition  of  storage,  may  be  obtained  by  ad- 
dressing Mr.  Franklin  H.  Wentworth,  Secretary,  87  Milk  St., 
Boston,  Mass. 

Installation  of  Mechanical  Features.  —  Proper  provision 
must  be  made  in  the  original  design  for  caring  for  all  such  me- 
chanical features  as  steam  pipes,  plumbing  pipes,  and  electric 
wires,  cables,  etc. 

In  a  building  of  any  considerable  size,  steam  risers  must 
usually  be  placed  at  several  locations  to  supply  radiators.  The 
best  method  of  caring  for  such  risers  is  to  place  them  within 
chases  or  slots  in  exterior  walls,  covering  them  with  removable 
metal  panels. 

Plumbing-  and  vent-pipes,  and  electric  cables,  etc.,  should  in- 
variably be  placed  within  a  special  shaft  which  should  preferably 
be  surrounded  by  brick  walls.  For  walls  of  pipe  shafts,  etc., 
see  Chapter  XVI.  A  tin-  or  metal-covered  door  and  frame  should 
be  provided  at  each  floor,  inside  of  which  should  be  placed  an 
iron  grating  to  fill  completely  the  shaft  area  except  for  a  suffi- 
cient opening  along  one  wall,  where  the  piping  and  cables  are 
run.  Easy  access  may  thus  be  had  at  each  floor  for  repairs, 
replacement,  etc. 

All  branches  from  this  main  shaft  should  be  so  run  as  not  to 
impair  the  efficiency  of  floor,  column  or  partition  construction. 
If  left  to  a  haphazard  installation,  as  is  only  too  often  done, 
piping  of  all  kinds  becomes  a  serious  menace  to  the  fireproofing 
scheme. 

Materials  and  Details.  —  The  materials  to  be  employed  for 
the  main  structural  members,  or  for  the  fire-resistive  coverings 
thereof,  should  be  those  which,  in  Chapter  VII,  were  found  to 
be  entirely  suitable  for  their  functions. 

The  details  of  construction,  such  as  floor  arches,  column 
coverings,  partitions,  the  protection  of  window  and  door  open- 
ings, stairways,  elevator-  and  other  shaft-enclosures,  walls,  roofs, 
etc.,  as  described  in  detail  in  succeeding  chapters,  must  all  be 
carefully  considered  in  so  far  as  such  details  affect  the  general 
plan  or  design. 


PLANNING   AND    GENERAL   DESIGN  315 

But  in  addition  to  the  consideration  of  the  main  structural 
materials  and  the  more  important  details  as  enumerated  above, 
it  should  be  the  consistent  aim  of  the  architect,  owner  and 
tenant  alike  to  reduce  the  combustible  or  damageable  materials 
in  the  building  to  a  minimum. 

Elimination  of  Combustible  or  Damageable  Materials. 
—  Reference  to  the  tabulated  percentages  of  cost  of  the  various 
items  of  work  entering  into  the  construction  of  fire-resisting 
buildings,  given  in  Chapter  VI,  will  show  the  high  percentage 
costs  of  those  portions  which  are  subject  to  complete  or  con- 
siderable damage  by  fire. 

In  the  paragraph  "  Ratio  of  Fire  Damage  to  Sound  Value, " 
page  202,  it  was  shown  that  the  losses  on  such  portions  of  even 
so-called  fire-resisting  buildings  in  the  Baltimore  and  San  Fran- 
cisco conflagrations  aggregated  from  60  to  70  per  cent,  of  the 
sound  value  of  such  buildings. 

The  paragraph,  " Minimizing  of  Fire  Losses:  Reconstruction," 
|  page  205,  quotes  the  recommendations  of  Captain  Sewell  as  to 
|  the  elimination,  as  far  as  may  be  practicable,  of  all  combustible 
or  easily  destructible  materials,  and  the  influence  of  such  design 
i  upon  the  feasibility  and  cost  of  reconstruction  after  fire  damage. 

It  has  previously  been  pointed  out  that  this  60  to  70  per  cent. 
|  of  loss  in  fire-resisting  buildings  under  conflagration  conditions 
'can  be  reduced  only  by:  1,  the  uniform  employment  of  fire- 
!  resisting  construction  in  congested  areas;  2,  more  efficient 
i  auxiliary  equipment,  and  3,  the  elimination  of  combustible  or 
;  damageable  materials. 

No  general  rules  can  be  laid  down  whereby  the  latter  require- 
ment can  best  be  accomplished,  for  each  building  will  largely  be 
a  problem  unto  itself.  Captain  Sewell  makes  many  valuable 
suggestions.  Fire-resisting  finished  floors  are  described  in 
Chapters  VII  and  XI;  partition  trim,  etc.,  is  discussed  in 
Chapter  XIII;  windows,  doors,  etc.,  in  Chapter  XIV;  roofs 
in  Chapter  XXI,  and  wall  finishes,  etc.,  in  Chapter  XX  and 
XXIV.  Still  further  practicable  reductions  in  combustible 
materials  through  the  use  of  metal  furniture,  shelving,  etc.,  is 
discussed  in  Chapter  XXVII. 

Fire  Departments  and  Equipment.  —  Over  and  above  all 
of  the  previously  mentioned  requisites  in  planning,  a  successful 
fire-resisting  design  must  include  provisions  for  two  very  im- 
portant elements  of  protection,  namely,  fire  department  opera- 


316  FIRE    PREVENTION    AND    FIRE    PROTECTION 

tions,  and  auxiliary  equipment  to  supplement  departmental 
efforts. 

The  efficiency  of  fire  department  work  will  depend  largely 
upon  the  subdivision  of  large  areas,  the  accessibility  of  all  areas, 
direct  and  non-confusing  corridors  or  means  of  communication, 
isolated  stair- wells,  and  well-planned  and  fire-resisting  stairs. 

Auxiliary  equipment  is  considered  in  detail  in  Part  VI  of  this 
volume. 

Then,  given  a  plan  in  which  suitability  of  use,  location, 
isolation  of  dangerous  risks,  the  subdivision  of  large  areas,  light- 
courts  and  well-rooms  have  each  and  all  been  properly  consid- 
ered and  provided  for,  the  whole  combined  with  a  suitable  but 
not  niggardly  fire-resisting  scheme  of  construction  and  suitable 
equipment,  and  we  may  rest  content  that  we  have  a  structure 
capable  of  resisting  the  most  severe  attacks  by  fire  and  water, 
requiring  only  a  minimum  of  repair  as  a  consequence. 


CHAPTER  X. 
EFFICIENCY   VS.   FAULTY   CONSTRUCTION* 

Haste  Detrimental  to  Efficiency.  —  A  candid  inquiry  into 
present-day  building  methods  —  regardless  of  national  pride, 
business  or  financial  interests,  —  forces  the  admission  that,  as 
a  nation,  we  are  decidedly  lacking  in  that  thoroughness,  super- 
vision, adequacy  and  permanency  which  should  properly  be 
looked  for  in  those  buildings  of  considerable  cost  which  now 
form  so  large  a  proportion  of  our  building  operations  in  large 
cities. 

Our  ofttimes  unwarranted  haste  and  consequent  carelessness, 
our  lack  of  consistent  thoroughness  in  fire-resistive  construc- 
tion, our  neglect  of  careful  and  searching  supervision  or  in- 
spection by  the  architect  or  engineer,  and  our  building  operations 
11  against  time,"  whereby  the  date  of  completion  to  insure  some 
advantageous  leases  or  rents  becomes  of  more  importance  than 
thoroughness  or  the  possibility  of  improving  the  work  through 
corrections  or  changes  as  the  work  progresses,  must  all  be 
admitted  as  highly  detrimental  to  efficient  and  permanent 
building  methods. 

Fire-resistive  Building  Methods.  —  Unfortunately,  the 
above  criticisms  are  particularly  true  of  buildings  intended  to 
be  of  fire-resistive  construction;  partly  because  this  class  of 
buildings  now  embraces  all  the  more  prominent  structures, 
partly  because  due  to  their  very  appellation  of  " fireproof"  or 
fire-resisting,  so  much  more  is  expected  of  them,  and  also  partly 
because  in  the  supposedly  fire-resisting  features  of  these  build- 
ings are  found  many  of  the  most  glaring  examples  of  that  haste, 
carelessness  and  inadequacy  which  are  so  to  be  deplored. 

There  is  no  question  that  many  buildings  are  constructed 
with  efficient  care  as  regards  permanency  against  sudden  fire, 
or  slow  deterioration  from  natural  causes.  The  wisdom  and 
permanency  of  steel-skeleton  methods  are  considered  in  another 

*  Portions  of  this  chapter  are  taken,  by  permission,  from  an  article  by  the 
author,  published  in  Engineering  News,  Vol.  LV,  No.  17. 

317 


318         FIRE)    PREVENTION    AND    FIRE    PROTECTION 

chapter,  and  there  is  ample  testimony  to  show  that  steel  build- 
ings and  concrete  buildings  can  and  are  being  made  safe  and 
permanent  for  any  length  of  life  which  may  reasonably  be  ex- 
pected of  them,  especially  where  care  and  a  sufficient  amount  of 
time  are  combined  with  proper  materials  and  adequate  super- 
vision. 

But,  unfortunately,  there  are  other  examples,  only  too  nu- 
merous, wherein  early  depreciation  or  deterioration  and  danger 
from  severe  or  total  fire- loss  are  only  too  imminent;  also  other 
examples  in  which  the  sins  are  rather  those  of  commission  than 
omission  —  of  "snide"  or  slighted  work. 

Faulty  Construction  Revealed  by  Baltimore  Conflagra- 
tion. —  If,  perchance,  the  above  views  are  thought  to  be  those 
of  an  alarmist,  consider  the  striking  testimony  as  to  honesty, 
efficiency  and  permanency  brought  out  in  the  Baltimore  confla- 
gration. Regarding  honesty,  what  of  the  large  areas  of  exterior 
masonry  walls  in  one  of  the  more  prominent  burned  "  fireproof " 
buildings  where  the  work  consisted  of  outer  and  inner  one-brick 
walls,  filled  in  with  loose  and  largely  uncemented  brickbats, 
broken  tile  and  almost  any  refuse? 

As  to  efficiency  or  permanency,  to  take  only  those  features 
of  fire-resistive  construction  which  should  have  been  fully  as 
well  understood  before  the  Baltimore  experience  as  after,  con- 
sider the  partition  construction  and  column  protections,  and 
the  almost  utter  failure  of  a  most  excellent  material  used  with- 
out intelligence;  the  totally  inadequate  floor  arches  used  in  the 
Equitable  Building;  and  the  complete  failure  of  various  cheap 
plaster-block  and  substitute  constructions,  introduced  under  false 
ideas  of  economy  and  efficiency. 

In  the  report  of  the  National  Fire  Protection  Association  on 
the  Baltimore  conflagration,  the  crying  need  of  less  haste  and 
more  care  in  building  operations  is  emphasized  as  follows: 

Municipal  building  laws  and  inspection  should  enforce  good 
construction  in  all  details.  Inspection  of  fire-resistive  buildings 
in  course  of  erection  should  be  more  frequent  than  is  necessary 
for  buildings  of  ordinary  construction.  One  of  the  most  dis- 
couraging features  brought  out  by  this  fire  is  the  wholesale 
evidence  of  lack  of  care  and  gross  neglect  in  the  execution  of 
the  work.  This  was  evidenced  in  many  ways,  such  as  chopping 
away  a  portion  of  the  floor  arches  for  the  purpose  of  applying 
ceiling  finish,  the  breaking  of  tile  column  coverings  for  pipes  and 
wires,  the  loose  setting  of  tile  partitions,  the  laying  of  curtain 


EFFICIENCY   VS.    FAULTY    CONSTRUCTION  319 

walls  without  sufficient  mortar,  and  the  poor  fastenings  of  the 
fire-protective  coverings  for  the  lower  flanges  of  beams  and 
girders  by  the  use  of  plaster,  metal  clips  and  even  wooden  strips. 

In  an  address  delivered  at  the  annual  banquet  of  the  National 
Board  of  Fire  Underwriters,  May  12,  1904,  Capt.  John  Stephen 
Sewell,  U.  S.  A.,  gave,  as  the  principal  lessons  to  be  drawn  from 
the  Baltimore  conflagration,  the  following: 

First.  In  our  designs  so  far,  we  have  resorted  to  inade- 
quate measures  for  fire-resistance,  and  almost  none  at  all  for 
fire  prevention.  .  .  . 

Second.  More  mass  is  required  to  resist  fire  than  to  carry 
superimposed  loads.  In  the  craze  for  lightness  and  cheapness, 
the  modern  fire-resisting  building  has  been  reduced  to  a  degree 
of  flimsiness  wholly  inconsistent  with  satisfactory  behavior  in 
a  severe  fire;  and  it  may  be  added  that  this  same  flimsiness  will 
insure  equally  unsatisfactory  results  against  the  slower  but 
always  active  elements. 

Third.  The  standard  of  workmanship  in  these  buildings 
is  very  low,  often  criminally  so.  The  factor  of  safety  pro- 
vided in  the  design  against  other  contingencies  is  drawn  upon 
for  100  per  cent,  as  tribute  to  dishonesty  and  carelessness. 
Owners  need  to  learn  the  value  and  the  necessity  of  adequate 
inspection,  and  it  does  seem  that  some  architects  should  enlarge 
their  ideas  of  what  is  meant  by  the  word  *  supervision.' 

Criticisms  of  San  Francisco  Buildings.  —  Mr.  Richard  L. 
Humphrey  states  that  the  causes  of  failures  of  buildings  by 
earthquake  and  fire  in  San  Francisco  may  be  summarized  as: 

1.  The  effort  on  the  part  of  those  qualified  to  design  and 
advise  on  building  construction  to  meet  the  owners7  demands 
by  planning  structures  so  that  they  can  be  erected  for  the  least 
possible  cost,  —  a  practice  which  tends  to  a  departure  from  the 
principles  of  correct  design,  the  result  being  a  structure  that 
will   carry   ordinary   loads,    but   that   fails   when   subjected   to 
unusual  conditions.  .  .  . 

2.  Actually  dishonest  design  and  construction.* 

The  report  of  Prof.  Frank  Soule*  in  the  same  bulletin  contains 
the  following: 

The  lessons  taught  by  the  great  Chicago  and  Baltimore  fires 
had  been  applied  by  but  few  of  the  architects  of  San  Francisco, 
on  account  of  cost  restrictions  insisted  on  by  owners,  and  very 
much  of  the  damage  inflicted  on  these  high-class  structures 
during  the  conflagration  is  directly  traceable  to  the  imperfect 
fireproofing  put  in,  or  to  the  entire  absence  of  fireproofing. 

*  Bulletin  No.  324,  United  States  Geological  Survey,  "The  San  Francisco 
Earthquake  and  Fire,"  pages  58,  147  and  149 


320         FIRE    PREVENTION   AND    FIRE    PROTECTION 

Some  of  the  failures  were  evidently  and  directly  attributable  to 
poor  workmanship. 

The  failure  of  the  plaster  and  metal  method  and  some 
other  methods  of  fireproofing  in  San  Francisco  is  directly  trace- 
able to  the  commands  of  owners  to  their  architects  to  cheapen 
as  far  as  practicable  the  fireproofing  and  the  construction  gen- 
erally, in  order  to  receive  greater  interest  on  their  investments. 
Much  of  this  cheapening  has  been  done  in  spite  of  the  protests 
of  the  designer,  and  it  is  in  an  entirely  wrong  direction;  for 
rates  of  insurance  are  largely  reduced  with  improvements  in 
fireproofing,  and  as  the  cost  of  the  steel  frame  and  its  proper 
fireproofing  seldom  exceeds  27  per  cent,  of  the  cost  of  the  build- 
ing, it  seems  wise  to  protect  the  other  73  per  cent,  with  ade- 
quate materials.* 

Causes  of  Faulty  Construction.  —  The  causes  of  these 
conditions  of  carelessness,  haste  and  inefficiency  are  therefore 
to  be  found  partly  with  the  owners  or  investors,  partly  with  the 
architect  or  engineer,  sometimes  with  the  contractor,  and  also 
frequently  in  the  laxness  of  our  building  regulations. 

Responsibility  of  Owner.  —  Considering  first  the  influence 
of  the  owner  or  investor  upon  such  questions,  it  is  apparent  that 
frenzied  building  finance  is  responsible  for  many  ills. 

Buildings  represent  the  investment  of  capital.  An  investor 
will  consider  long  and  carefully  the  purchase  of  a  valuable  piece 
of  real  estate,  yet  when  he  comes  to  improve  that  real  estate  by 
a  building  scheme  costing  possibly  as  much  as  the  land  value, 
the  safe,  lasting  and  genuine  qualities  of  the  structure  are  con- 
sidered of  far  less  importance  than  economy  in  planning,  ex- 
terior attractiveness,  and  haste  to  realize  on  the  investment. 
This  is  particularly  true  of  speculative  building  or  property 
to  be  turned  over  to  others,  often  to  small  investors  in  the 
shares  of  building  trusts,  who  have  no  means  of  knowing  that 
the  work  has  been  rushed  or  skimped,  but  who  see  only  the 
veneer  and  apparent  excellence.  The  writer  has  watched  care- 
fully such  an  example  of  building.  Owing  to  haste  and  care- 
lessness, the  first  winter  after  the  owners  had  "sold  out"  found 
tenants  freezing  from  inadequate  heating  plant  combined  with 
poor  construction,  while  within  a  year  not  a  door  in  the  building 
closed  tightly.  What  unjust  loads  of  repair,  renewal  and  often 
total  loss  thus  come  upon  holders  of  such  false-pretence  property! 

A  good  building  requires  time  to  construct.     Modern  "rush" 

*  Bulletin  No.  324,  United  States  Geological  Survey,  "  The  San  Francisco 
Earthquake  and  Fire,"  pages  58,  147  and  149. 


EFFICIENCY   VS.    FAULTY   CONSTRUCTION  321 

tendencies  to  get  the  building  done  by  a  certain  date,  regardless 
of  workmanship,   are  pernicious  in  the  extreme.     The  owner 
requiring  such  a  contract  deliberately  invites  slighted  work  on 
the  part  of  the  contractor  and  slighted  supervision  on  the  part 
of  the  architect.     Mechanics  can  perform,  honest  work  for  not 
over  nine  or  ten  hours  a  day.     Night  gangs  can  never  equal 
i  day  gangs  in  excellence  of  work.     The  architect,  under  press 
'•'.  of  a  time  contract,  will  be  forced  to  pass  mediocre  work  rather 
;  than  take  the  responsibility  of  delaying  the  completion,   and 
I  this  knowledge  is  apt  to  be  taken  advantage  of  by  the  un- 
scrupulous contractor. 

Then  the  indifference  of  the  average  owner  to  adequate  fire- 
resistance  shifts  the  burden  of  fire  loss  upon  the  community  in 
the  shape  of  fire  insurance.  The  moral  duty  of  erecting  a  unit 
of  fire-resistance,  contributing  to  the  safety  and  rights  of  one's 
neighbors,  is  becoming  more  and  more  recognized,  and  the  com- 
paratively slight  difference  in  expense  between  adequate  effective 
fireproofing  and  the  methods  of  proven  inefficiency  should  not 
be  set  down  to  extravagance  or  foolish  precaution,  but  to  a 
common-sense  view  of  one's  obligations  to  neighbor  and  self. 

There  is,  finally,  a  phase  of  this  subject  which  has  not 
yet  been  touched  upon  —  the  commercial  side.  The  writer's 
long  experience  in  the  business  of  contracting  for  fireproof  con- 
struction has  afforded  exceptional  opportunity  to  study  the 
attitude  of  capitalists,  owners  and  architects  on  this  subject. 
It  will  no  doubt  be  a  surprise  to  many  to  learn  that  in  more 
than  95  per  cent,  of  the  fireproof  buildings  erected  during  the 
last  five  years  the  mistaken  economy  of  owners  and  their  repre- 
sentatives has  prevented  the  adoption  of  good  fireproof  con- 
struction in  that  proportion  of  buildings.  In  every  case  the 
difference  between  a  poor  and  mediocre  method  of  fireproofing 
and  a  first-class  and  efficient  method  has  not  been  in  excess  of 
from  2  to  4  per  cent,  of  the  cost  of  the  building.  As  long  as  a  cheap 
method  or  system  of  fireproofing  complies  with  the  building  laws 
of  the  city  in  which  the  building  is  to  be  located,  and  fulfils  the 
requirements  for  strength,  the  average  owner  is  satisfied,  and 
is  unwilling  to  appropriate  any  additional  money  whatever  for 
superior  methods  or  materials.  It  is  the  same  old  story  of 
'just  as  good'  substitution. 

When  the  owner,  as  is  generally  the  case,  has  no  practical 
knowledge  of  building  construction,  and  is  incapable  of  judging 
of  the  merits  of  different  methods  and  materials,  he  invariably 
adopts  the  lowest-priced  method  or  system  offered,  or  instructs 
his  architects  or  representatives  to  do  so.  One  of  the  incom- 
prehensible things  is  the  fact  that  the  average  owner,  or  his 


322          FIRE    PREVENTION    AND   FIRE    PROTECTION 

business  representative,  thinks  that  he  is  fulfilling  every  moral 
and  business  obligation  by  offering  to  award  the  work  to  the 
concerns  furnishing  first-class  and  efficient  methods  at  the  same 
price  that  the  poorest  and  cheapest  methods  are  offered  to  him. 
This  policy  and  method  of  placing  contracts  for  fireproof  con- 
struction is  used  almost  without  exception,  even  by  large  rail- 
roads and  wealthy  corporations. 

In  the  case  of  all  other  building  materials,  such  as  stone, 
brick,  steel,  cement,  etc.,  quality  is  carefully  considered,  and  the 
prices  are  graded  accordingly;  but  in  the  consideration  and 
selection  of  fireproof  construction,  which  is  probably  the  most 
important  detail  of  a  modern  building,  quality  and  efficiency 
have  been  entirely  neglected  up  to  the  present  time. 

As  long  as  owners  and  architects  are  unwilling  to  pay  the 
small  additional  amount  necessary  to  secure  first-class  fire- 
proofing  they  must  expect  results  such  as  were  shown  in  Balti- 
more and  San  Francisco  whenever  a  conflagration  of  any 
magnitude  occurs.  It  would  seem,  however,  that  the  exercise 
of  the  most  ordinary  intelligence  would  prompt  the  owner  of  a 
valuable  building  to  expend  from  2  to  4  per  cent,  of  its  cost,  in 
order  to  secure  exemption  from  damage  to  the  structural  parts 
of  the  building,  and  an  additional  5  per  cent,  for  the  protection 
of  exterior  window  and  door  openings,  in  order  to  save  the 
contents  of  the  building  from  exterior  attack  by  fire.* 

Responsibility  of  Architect.  —  The  architect  —  that  is, 
the  average  architect,  for  there  are  notable  exceptions  —  con- 
tributes to  inefficient  building  methods  through  lack  of  knowl- 
edge regarding  constructive  principles,  lack  of  care  and  often 
interest  in  vital  details  of  fire-resistive  planning  or  details  of 
construction,  and  lack  of  rigid,  intelligent  inspection  of  ma- 
terials and  workmanship,  especially  the  latter.  For  examples, 
take  the  instance  of  hollow  masonry  walls  filled  with  rubbish, 
revealed  by  the  Baltimore  fire,  before  stated,  the  apparent 
lack  of  inspection  given  the  terra-cotta  arch  construction  in 
the  Park  Row  Building,  f  and  the  poor  concrete  work  exhibited 
in  the  beam  protection  of  the  Butterick  Building,  both  of 
these  buildings  being  in  New  York  City.  Examples  need  not 
be  multiplied.  There  is  ample  room  for  improvement  in  the 
matter  of  more  fully  detailing  important  elements  of  the  work, 
insisting  upon  more  mass  or  adequacy  of  material  to  prevent 
fire  destruction  or  the  ravages  of  deterioration,  more  complete 
and  intelligent  specifications,  and  the  rigid  enforcement  of  all 
by  painstaking  inspection. 

*  A.  L.  A.  Himmelwright,  M.  Am.  800.  C.  EM  in  Trans.  Am.  Soc.  C.  E  . 
Vol.  LIX,  page  309. 

f  See  Engineering  News,  April  14,  1898. 


EFFICIENCY   VS.    FAULTY    CONSTRUCTION  323 

Responsibility  of  Contractor.  —  The  contractor,  between 
the  devil  of  competition  and  the  deep  sea  of  no  work,  is  obliged 
to  take  work  on  a  time  basis  which  he  knows  is  incompatible 
with  best  results,  thereby  assenting  to  a  wilful  slighting  of  the 
character  of  the  work.  While  some  builders  who  are  making 
records  for  mushroom-growth  building  operations  may  be  con- 
tributing to  our  national  reputation  for  "  hustle, "  they  are 
certainly  contributing  little  to  the  true  and  lasting  qualities  of 
the  building  methods  of  the  "old-school"  contractors  of  one  or 
two  generations  ago. 

Conclusions.  —  First,  it  will  be  well  to  recognize  clearly  that 
in  the  matter  of  the  use  or  application  of  fire-resisting  materials, 
solidity,  mass  or  adequacy  are  practically  synonymous  with 
efficiency;  for  inadequate,  skimped  or  slighted  work  will,  sooner 
or  later,  prove  a  menace  to  the  life  of  the  structure  —  if  not 
under  some  sudden  fire  test,  then  under  the  slow  but  sure  ravages 
of  time.  For  fire-protective  coverings  are  employed  not  alone 
as  such,  but  as  a  protection  to  the  vital  steel  skeleton  as  well. 
Any  paring  down  of  these  protective  coverings,  therefore,  en- 
dangers the  ultimate  life  of  the  steel  frame,  in  addition  to  in- 
viting disaster  from  some  sudden  and  unexpected  trial  by  fire. 

If  fireproofing  is  worth  attempting  at  all,  it  is  worth  doing 
well.  No  one  would  think  of  skimping  the  essential  structural 
portions  of  a  building  to  a  dangerous  degree.  In  few  of  our 
building  materials  is  a  factor  of  safety  of  less  than  2  employed  — 
in  fact,  it  usually  runs  from  2|  to  5.  Why  then  should  a  doubt- 
ful sufficiency —  indeed,  often  no  factor  of  safety,  but  a  real 
deficiency  —  be  tolerated  in  fire-protective  materials?  Surely 
not  from  lack  of  experience  or  illustrations,  for  past  fires  have 
clearly  demonstrated  failure  after  failure  in  the  efficiency  of 
many  recognized  "standard"  details  of  construction,  not  so 
often  in  the  materials  themselves  as  in  the  method  of  application 
and  the  inadequacy  of  material. 

Second,  good  fire-resistive  construction  always  shows  good 
results  and  poor  fire-resistive  construction  shows  poor  results. 
Too  rapid,  careless  or  flimsy  construction  is  not  only  detrimental 
to  trustworthy  fireproofing,  but  is  equally  detrimental  to  the 
permanency  of  the  structure.  Poor  fireproofing,  also,  is  apt  to 
be  a  total  loss  under  severe  fire  test,  while  good  fireproofing,  even 
if  somewhat  damaged,  will  permit  of  speedy  reconstruction. 


CHAPTER  XL 

FIRE-RESISTING  FLOOR  DESIGN,  BEAM-AND-GIRDER 
PROTECTIONS,    CEILINGS. 

Requirements.  —  A  satisfactory  fire-resisting  floor  design 
should,  in  so  far  as  may  be  possible,  combine  the  following 
features : 

Strength  and  rigidity,  —  including  ability  to  carry  the  esti- 
mated static  and  moving  loads  with  a  proper  factor  of  safety, 
and  ability  to  resist  shock  due  to  falling  debris. 

Fire-  and  water-resistance,  —  to  secure  a  minimum  damage  by 
fire  and  water,  especially  as  regards  beam-  and  girder-protections, 
and  to  make  floors  waterproof. 

Protection  against  corrosion,  —  in  providing  protection  to  all 
metal  beams,  girders,  etc.,  and  to  metal  reinforcement,  if 
employed. 

Low  cost  and  ease  of  reconstruction,  —  to  secure  simplicity  of 
construction,  not  involving  skilled  labor;  a  minimum  dead  weight 
in  the  construction;  and  a  minimum  cost  of  reconstruction  after 
damage  by  fire. 

As  to  a  selection  of  floor  type  to  combine,  in  so  far  as  may  be 
possible,  the  above  desiderata,  see  paragraph  "  Selection  of 
Floor  Type,"  page  345. 

Types  of  Fire-resisting  Floors  employed  in  present  practice 
for  various  classes  of  fire-resisting  buildings  comprise:  Mill  con- 
struction, brick,  terra-cotta,  concrete,  and  combination  terra- 
cotta and  concrete.  In  addition  to  these,  a  great  number  of 
patented  "systems"  have  been  used  during  the  past  ten  or 
fifteen  years,  practically  none  of  which  has  survived  the  test 
of  time  save  the  Guastavino  construction.  Probably  ninety- 
five  per  cent,  of  present-day  fire-resisting  floor  construction  con-, 
sists  of  tile  arches  of  some  form,  reinforced  concrete,  or  combined 
tile  and  concrete. 

The  Building  Code  recommended  by  the  National  Board  of 
Fire  Underwriters  allows  fire-resisting  floors  to  be  made  of  brick 
arches,  hollow  tile  arches,  or  arches  of  plain  or  reinforced  Port- 

324 


FIRE-RESISTING    FLOOR   DESIGN,    ETC.  325 

land  cement  concrete,  all  within  stated  requirements.  Other 
than  standard  forms  of  brick,  tile,  concrete  or  composition  floors 
must  be  subjected  to  a  standard  load-,  fire-  and  water-test,  prac- 
tically the  same  as  that  described  in  Chapter  V,  page  123. 

Mill  Construction  Floors  have  been  described  in  detail 
in  Chapter  IV.  Combination  mill  construction  and  concrete 
floors  of  the  Wilson  system  are  also  described  in  Chapter  XXV. 

Brick  Floor  Arches  are  now  comparatively  seldom  used  on 
account  of  their  heavy  weight  and  high  cost,  but  for  very  heavy 
loads  they  are  about  the  strongest  type  which  can  be  employed. 
"A  4-inch  brick  arch  of  6-foot  span,  well  grouted  and  leveled 
off  with  Portland  cement  concrete,  should  safely  carry  300  or 
400  pounds  to  the  square  foot.  Experiments  have  shown  that 
brick  arches  will  stand  very  severe  pounding  and  a  great  amount 
of  deflection  without  failure."* 

The  National  Code  requirements  for  brick  arches  are  partly 
as  follows: 

Said  brick  arches  shall  be  designed  with  a  rise  to  safely 
carry  the  imposed  load  but  never  less  than  1J  ins.  for  each  foot 
of  span  between  the  beams,  and  they  shall  have  a  thickness  of  not 
less  than  4  ins.  for  spans  of  6  ft.  or  less,  and  8  ins.  for  spans  over 
6  ft.,  or  additional  thickness  as  may  be  required  by  the  commis- 
sioner of  buildings.  Said  arches  shall  be  composed  of  good,  hard 
brick  or  hollow  brick,  .  .  .  each  longitudinal  line  of  brick  break- 
ing joints  with  the  adjoining  lines  in  the  same  ring  and  with  the 
ring  under  it  when  more  than  a  4-in.  arch  is  used.  The  said 
arches  shall  spring  from  protecting  skewbacks  of  burnt  clay 
resting  on  and  covering  the  lower  flanges  of  the  beams,  so  as  to 
afford  a  minimum  protection  of  2  ins.  of  solid  burnt-clay  material 
underneath  the  flanges,  or  otherwise  entirely  encasing  the  said 
flanges  as  provided  for  in  this  section. 

The  Government  Printing  Office  at  Washington,  D.  C.,  is  a 
notable  example  of  a  modern  fire-resisting  building  in  which 
brick  floor  arches  were  used.  All  floors  were  proportioned  for  a 
maximum  dead  load  of  125  pounds  per  square  foot,  and  a  quies- 
cent live  load  of  300  pounds  per  square  foot.  The  floor  construc- 
tion is  as  shown  in  Fig.  47. 

The  machines  in  the  building  are  driven  by  a  large  num- 
ber of  individual  electric  motors,  and,  as  it  is  necessary  from  time 
to  time  to  change  the  arrangement  of  the  machines  and  the 
electric  lights,  the  floor  system  was  designed  with  especial  refer- 
ence to  the  convenience  of  relocating  the  motors  and  wiring 

*  Kidder's  "Architects'  and  Builders'  Pocket-book,"  page  749. 


326 


FIRE   PREVENTION   AND    FIRE    PROTECTION 


system  so  that  holes  could  be  easily  cut  through  or  be  filled 
up  in  any  place  without  injury  to  the  strength  of  the  con- 
struction. Lights  suspended  from  the  ceilings  must  also  be 
moved  without  disfiguring  the  ceiling,  and  it  was  decided  to 
take  advantage  of  the  space  afforded  by  the  depth  of  the  long 
span  girders  to  make  the  floors  and  ceilings  separate  with  suffi- 
cient space  between  them  for  a  man  to  pass  through  all  places 
between  girders,  and  to  run  all  wires  and  cables  in  this  space 


Finished  Floor 


. 

3  Bars  5  on  Centers 
-^Finished  Plastering 
-Wire  Cloth  V^ 
Terra-Cotta'    Cement  and  Sand 

FIG.  47.  —  Brick  Arch  Construction  in  United  States  Printing  Office, 
Washington,  D.  C. 

where  they  are  protected  from  fire  and  are  always  accessible 
through  manholes.  To  this  end  the  floors  have  been  built  and 
the  girders  fireproofed  as  shown,  and  then  the  wiring  has  been 
done  before  the  ceilings  were  built.  .  .  . 

The  segmental  floor  arches  4  inches  thick  are  made  as 
shown  in  the  detail  sections,  with  solid  porous  terra-cotta  bricks 
set  on  very  heavy  skewbacks  of  the  same  material  which  have 
projecting  lips  1J  inches  thick  to  protect  the  lower  flanges  of 
the  floor  beams.  These  lips,  which  are  usilally  the  weakest 
point  of  a  beam  protection,  meet  with  a  very  thin  mortar  joint 
and  are  believed  to  be  strong  enough  to  resist  any  ordinary  fire 
stream  unless  accompanied  by  prolonged  and  very  intense  heat. 
Where  it  would  have  been  difficult  to  build  the  brick  arches  on 
account  of  irregular  beam  framing  or  where  if"was  desired  to 
have  a  sloping  floor  on  level  beams,  the  arches  were  replaced  by 
steel-concrete  slabs  with  the  beams  entirely  enclosed  in  the 
concrete.  .  .  . 

The  lower  flanges  of  the  main  ^girders  are  protected  by 
shoes  of  solid  porous  terra-cotta,  2f  inches  thick,  filled  with 
mortar  and  squeezed  on.  They  a/e  then  wrapped  with  wire 
lath,  plastered  with  cement  mortar,  and  the  4-inch  walls  of 
solid  porous  terra-cotta  are  built  up  each  side  of  the  girder  web, 
and  the  spaces  between  the  terra-cotta  and  the  girder  are  filled 
solid  with  cement  mortar.  .  .  . 


FIRE-RESISTING    FLOOR    DESIGN,    ETC. 


327 


The  ceiling  beam3  are  3  inches  deep,  about  3  feet  apart, 
and  support  on  their  lower  flanges  transverse  T-bars  2  feet 
apart.  These  T-bars  carry  2-inch  slabs  of  cement  and  sand, 
reinforced  with  steel  rods.* 

Brick  arches  as  used  in  the  driveway  of  the  United  States 
Court  House  and  Post  Office  at  Los  Angeles,  Cal.,  are  shown  in 
Fig.  48.  The  construction  consists  of  a  4-inch  brick  arch,  with 
J-in.  tie  rods  6  ft.  centers,  concrete  leveling  up  to  1J  ins.  above 


^'Granolithic  v 


1:2:5  Stone  Concrete 


/Viator-proofing 


FIG.  48.  —  Brick  Arch  Construction  in  Post  Office  Building,  Los  Angeles,  Cal. 

beams,  a  waterproofing  course  of  three  layers  of  asphalt  felt  laid 
in  hot  asphalt,  4  ins.  of  stone  concrete,  and  a  1-in.  granolithic 
finish. 

Terra-cotta  Floor  Arches  are  considered,  as  to  various 
phases,  in  other  chapters,  as  follows: 

Behavior  of  tile  arches  in  actual  fires  and  conflagrations, 
Chapters  VI,  VII  and  XVII. 

The  fire-resisting  qualities  of  the  different  varieties  of  terra- 
cotta, Chapter  VII. 

Present  forms  of  terra-cotta  floor  arches,  etc.,  Chapters  XVII 
and  XXIV. 

Tests  of  terra-cotta  floors,  Chapter  XVII. 

Combination  terra-cotta  and  concrete  floors,  Chapters  XIX 
and  XXIV. 

Concrete  Floors  are  considered,  as  to  various  phases,  in 
other  chapters  as  follows: 

The  fire-resisting  qualities,  thermal  conductivity,  etc.,  of  con- 
crete, also  the  behavior  of  concrete  in  the  San  Francisco  fire, 
Chapter  VII. 

The  protective  and  corrosive  qualities  of  concretes,  Chapter 
VIII. 

*  The  Engineering  Record,  December  6,   1902. 


328         FIRE    PREVENTION    AND    FIRE    PROTECTION 

Present  forms  of  concrete  floor  construction,  Chapters  XVIII 
and  XXV. 

Tests  of  concrete  floors,  Chapter  XVIII. 

Combination  terra-cotta  and  concrete  floors,  Chapters  XIX 
and  XXIV. 

Combination  concrete  and  mill-construction  floors,  Chapter 
XXV. 

Guastavino  Floor  and  Dome  Construction.  —  The  Guas- 
tavino  Timbrel  Vault  construction,  though  not  so  generally 
comprehended  as  most  of  the  modern  commercial  types  of 
fire-resisting  arches,  is,  in  fact,  the  oldest  special  system  in  con- 
tinuous application  in  this  country.  It  was  first  installed  in  a 
large  way  in  the  Arion  Club  in  New  York  City  in  1886,  and  in 
1889-91  were  built  the  floors  of  the  Boston  Public  Library,  all 
of  which  are  of  the  Guastavino  type.  These  arches  presented 
practically  the  same  problems  and  methods  as  are  used  today. 
There  has  been  no  change  in  the  principle,  simply  a  wider 
application  and  a  gradual  turning  towards  finished  and  decora- 
tive effects  through  the  use  of  pressed  and  glazed  tile  in  the  soffit 
course,  a  construction  with  incidental  decoration. 

This  system  was  introduced  into  this  country  by  Mr.  Rafael 
Guastavino,  an  architect  and  native  of  Spain.  It  is  simply  an 
adaptation  of  ancient  methods  to  modern  materials  through  the 
use  of  thin  tiles  about  1  inch  in  thickness  and  6  inches  in  width 
and  in  various  lengths,  and  of  the  necessary  number  of  courses 
to  give  the  required  strength,  securing  through  this  method,  by 
laying  in  broken  joints,  a  large  bonding  area  making  a  light  and 
thoroughly  cohesive  arch. 

It  is  best  adapted,  and  has  been  many  times  applied,  to  all 
the  various  forms  of  architectural  vaulting,  such  as  the  large 
barrel  or  segmental  arch,  running  up  to  a  span  of  70  feet,  as 
illustrated  in  the  ceiling  of  the  Fine  Arts  Building  at  St.  Louis, 
Cass  Gilbert,  architect;  the  groined  and  four-sided  arch,  as 
used  in  the  construction  of  the  roof  of  the  Rodef  Shdlem  Syna- 
gogue at  Pittsburgh,  Palmer  and  Hornbostel,  architects  (a  clear 
span  of  90  feet,  sprung  from  a  rectangular  base,  with  no  steel); 
the  spherical  dome,  as  built  in  the  Cathedral  of  St.  John  the 
Divine,  Heins  and  La  Farge,  architects  (with  a  span  of  135  feet 
at  the  base,  the  dome  being  built  overhand  without  centering 
or  scaffolding);  and  the  floor  dome  of  varying  sizes,  reaching 
a  present  maximum  in  the  dome  of  the  National  Museum  at 


FIRE-RESISTING    FLOOR    DESIGN,    ETC. 


329 


Washington,  Hornblower  and  Marshall,  architects,  (a  clear  span 
of  80  feet,  without  steel,  forming  the  largest  masonry  floor  dome 
in  the  world).  Under  ordinary  conditions  for  work  of  this  char- 
acter involving  large  free  spans,  particularly  for  roofs,  there  is 
no  system  of  such  economical  application. 

The  most  common,  economical  and  efficient  type  of  floor  con- 
struction in  this  vaulting  is  what  is  called  the  "rib  and  dome," 
an  illustration  of  which  is  given  in  Fig.  49,  which  shows  the  first 


FIG.   49.  - 


-  Guastavino   Construction,   Chicago  and   Northwestern  Terminal 
Chicago.     Frost  and  Granger,  architects. 


floor  ceiling  of  the  new  Chicago  and  Northwestern  Terminal  at 
Chicago,  Frost  and  Granger,  architects.  This  photograph  shows 
the  glazed-tile  domes  in  bays  of  about  20  feet  by  30  feet.  Rest- 
ing on  these  domes  is  built  the  Guastavino  bridges  and  flatwork 
construction,  which  forms  the  floor  of  the  main  rotunda  of  this 


construe! 


330         FIRE    PREVENTION   AND    FIRE    PROTECTION 

building,  and  which  is  designed  for  a  safe  load  of  400  pounds  per 
square  foot. 

Design  of  Floor  System.*  —  The  type  of  floor  arch  selected 
for  any  particular  building  will  largely  determine  the  conditions 
of  the  steel  framing.  Thus,  if  any  of  the  "long-span"  construc- 
tions is  to  be  used,  such  as  the  Johnson  system,  or  long-span 
reinforced  concrete,  the  columns  should  be  spaced  so  as  to  divide 
the  floor  area  into  bays  of  a  proper  length  and  width  to  suit  the 
economical  use  of  the  type  of  arch  selected.  For  such  cases, 
floor  beams  are  not  required,  but  girders  only  are  run  from 
column  to  column.  If  the  arch  is  segmental  in  form,  tie-rods 
are  necessary. 

If  a  short  span  or  ordinary  construction  is  to  be  used,  the  bays 
must  be  divided  by  floor  beams,  spaced  ordinarily  5  ft.  to  7  ft. 
centers. 

Before  these  steel  girders  and  beams  can  be  calculated  as  to 
strength,  the  question  of  floor  loads  must  be  determined. 

Floor  Loads.  —  The  loads  usually  affecting  the  floor  system 
are: 

Dead  Loads,  comprising  the  weight  of  girders  and  beams,  the 
arch,  concrete  or  other  filling,  suspended  ceiling,  if  used,  plaster- 
ing, screeds,  and  finished  flooring. 

Note.  —  In  office  buildings,  partitions  between  offices  are 
usually  rated  as  dead  load  at  so  much  per  square  foot  of  floor 
surface,  owing  to  the  liability  of  change  in  position,  to  suit  the 
requirements  of  tenants. 

Dead  loads,  sufficiently  accurate  for  use  in  calculating  the 
steel  members,  are  given  for  many  types  of  floors  described  in 
Chapters  XVII,  XVIII  and  XIX. 

Other  data  useful  in  estimating  the  dead  load  of  floors  are 
as  follows: 

Lb.  per  sq.  ft. 

f-in.  Georgia  pine  or  maple  flooring 4 

|-in.  spruce  under  flooring 2 

Cement  tile  or  marble  floors,  1  in.  thick 10 

Cinder  concrete,  per  inch  of  thickness 9j 

Two  coats  plaster  on  soffit  of  floor  arches 6 

Suspended  ceiling  with  three  coats  plaster 9 

*  For  a  more  extended  discussion  of  Floor  Design,  including  Beams,  Girders, 
Methods  of  Calculation,  etc.,  see  the  author's  "Architectural  Engineering," 
John  Wiley  &  Sons. 


FIRE-RESISTING    FLOOR    DESIGN,    ETC.  331 

Live  loads,  comprising  the  people  in  the  building,  furniture, 
movable  contents  and  small  safes,  etc.,  are  usually  specified  in 
local  building  ordinances,  according  to  the  purposes  for  which 
the  building  is  intended.  If  the  designer  is  not  limited  by  such 
requirements,  the  following  live  loads,  recommended  in  the 
National  Code,  may  be  used: 

Dwellings,  apartment  houses,  hotels  and  lodging  houses, 
60  Ibs.  per  sq.  ft. 

Office  buildings,  150  Ibs.  on  first  floor,  75  Ibs.  on  upper 
floors. 

Schools  and  stables,  75  Ibs.  per  sq.  ft. 

Place  of  public  assembly,  90  Ibs.  per  sq.  ft. 

Ordinary  stores,  light  manufacturing  arid  light  storage,  125 
Ibs.  per  sq.  ft. 

Heavy  storage,  warehouses  and  factories,  150  Ibs.  per  sq.  ft. 

Roofs,  pitch  less  than  20  degrees,  50  Ibs.  per  sq.  ft. 

Roofs,  pitch  over  20  degrees,  30  Ibs.  per  horizontal  ft. 

Calculations  of  Beams  and  Girders.  —  Even  ordinary 
practice  includes  such  great  variations  in  dead  loads,  (due  to 
the  construction  used),  —  in  live  loads,  (due  to  conditions  of 
loading),  —  and  in  widths  of  arch  spans  and  lengths  of  panels, 
that  tables  of  floor-beam  sizes  and  weights,  of  any  general 
applicability,  are  well-nigh  impossible.  For  usual  conditions 
the  floor  beams  may  be  determined  by  means  of  the  tables  for 
"safe  distributed  loads"  as  given  in  the  handbooks  issued  by 
some  of  the  steel  companies.  These  tables  give  the  loads,  in 
tons  of  2000  pounds,  which  the  various  sizes  and  weights  of 
beams  and  channels  will  safely  carry  (distributed  uniformly 
over  the  length)  for  distances  between  supports  as  tabulated. 

Or,  if  a  section  is  to  be  selected  to  carry  a  certain  load  for  a 
length  of  span  already  fixed,  as  is  usually  the  case  in  building 
design,  the  required  beam  or  channel  may  be  determined  by 
means  of  the  coefficients  given  in  tabular  form  for  all  rolled 
sections.  For  a  uniformly  distributed  load  these  coefficients 
are  obtained  by  multiplying  the  load,  in  pounds  uniformly  dis- 
tributed, by  the  span  length  in  feet.  Such  maximum  coefficients 
of  strength  for  I-beams  and  channels  of  different  sizes  and 
weights  per  foot  are  given  in  the  handbooks  issued  by  the 
Carnegie  Steel  Company,  and  the  Pencoyd  Iron  Works,  etc. 

Beam  tables  for  three  conditions  of  loading  are  given  in  the 
following  paragraph. 


332         FIRE    PREVENTION   AND    FIRE    PROTECTION 

For  the  simplest  cases,  girders  may  also  be  determined  by 
means  of  coefficients,  as  explained  above.  If  the  beam  load  to 
be  carried  by  the  girder  occurs  at  its  center  point,  multiply  the 
concentrated  beam  load  by  2,  and  then  consider  it  as  uniformly 
distributed.  If  the  girder  supports  beams  of  equal  loads  at 
points  distant  one-third  the  span  from  each  end,  the  equivalent 
uniformly  distributed  load  on  the  girder  may  be  found  by 
multiplying  one  of  the  concentrated  beam  loads  by  2|. 

Beam  Tables.  —  "The  following  tables  may  be  used  in 
making  approximate  estimates  and  in  checking  the  computa- 
tions for  any  particular  floor.  The  sizes  of  I-beam  given  may 
be  safely  used  where  the  total  live  and  dead  load  does  not  exceed 
the  value  given  in  the  headings.  The  total  load  should  include 
sufficient  allowance  for  the  weight  of  any  partitions  that  the 
floor  beams  may  be  called  upon  to  support."* 


SIZES  AND  WEIGHTS  OF  I-BEAMS  FOR  FLOORS  IN  OFFICES, 
HOTELS  AND  APARTMENT  HOUSES. 

Total  load,  120  pounds  per  square  foot. 


Span 
of 
beams 
in  feet. 

Distance  between  centers  of  beams. 

4£  feet. 

5  feet. 

5^  feet. 

6  feet. 

7  feet. 

10 

Ins. 

6 

Lbs. 

121 

Ins. 
6 

Lbs. 

Ins. 
6 

Lbs. 

Ins. 
6 

Lbs. 

Ins. 

7 

Lbs. 
15 

11 

6 

6 

12} 

7 

15* 

7 

15* 

7 

15 

12 

6 

12} 

7 

15 

7 

15 

7 

15 

8 

18 

13 

7 

15 

7 

15 

7 

15 

8 

18 

8 

18 

14 

7 

15 

8 

18 

8 

18 

8 

18 

9 

21 

15 

8 

18 

8 

18 

8 

18 

9 

21 

9 

21 

16 

8 

18 

9 

21 

9 

21 

9 

21 

10 

25 

17 

9 

21 

9 

21 

9 

21 

10 

25 

10 

25 

18 

9 

21 

9 

21 

10 

25 

10 

25 

12 

31} 

19 

9 

21 

10 

25 

10 

25 

10 

25 

12 

31} 

20 

10 

25 

10 

25 

12 

311 

12 

31} 

12 

31} 

21 

10 

25 

12 

31} 

12 

31} 

12 

31} 

12 

31} 

22 

10 

25 

12 

31| 

12 

31} 

12 

31} 

15 

42 

23 

12 

31J 

12 

31} 

12 

31} 

12 

31} 

15 

42 

24 

12 

31} 

12 

31} 

12 

31} 

15 

42 

15 

42 

25 

12 

31  J' 

12 

31} 

15 

42 

15 

42 

15 

42 

*  Rudolph  P.  Miller,  in  Kidder's  "Architects'  and  Builders'  Pocket-book." 


FIRE-RESISTING   FLOOR   DESIGN,    ETC. 


333 


SIZES  AND  WEIGHTS  OF  I-BEAMS  FOR  FLOORS  IN   RETAIL 

STORES  AND  ASSEMBLY   ROOMS. 

Total  load,  200  pounds  per  square  foot. 


Span 

Distance  between  centers  of  beams. 

of 

beams 

in  feet. 

4£  feet. 

5  feet. 

5£  feet. 

6  feet. 

7  feet. 

Ins. 

Lbs. 

Ins. 

Lbs. 

Ins. 

Lbs. 

Ins. 

Lbs. 

Ins. 

Lbs. 

10 

7 

15 

7 

15 

7 

15 

8 

18 

8 

18 

11 

7 

15 

8 

18 

8 

18 

8 

18 

9 

21 

12 

8 

18 

8 

18 

9 

21 

9 

21 

9 

21 

13 

8 

18 

9 

21 

9 

21 

10 

25 

10 

25 

14 

9 

21 

9 

21 

10 

25 

10 

25 

12 

311 

15 

9 

21 

10 

25 

10 

25 

12 

311 

12 

31} 

16 

10 

25 

10 

25 

12 

311 

12 

311 

12 

311 

17 

10 

25 

12 

31i 

12 

311 

12 

311 

12 

40 

18 

12 

31* 

12 

31J 

12 

811 

12 

40 

12 

40 

19 

12 

3ii 

12 

311 

12 

40 

12 

40 

15 

42 

20 

12 

31} 

12 

40 

12 

40 

15 

42 

15 

42 

SIZES  AND  WEIGHTS  OF  I-BEAMS  FOR  FLOORS   IN  WARE- 
HOUSES. 

Total  load,  270  pounds  per  square  foot. 


Span 

Distance  between  centers  of  beams. 

of 

beams 

in  feet. 

4J  feet. 

5  feet. 

5£  feet. 

6  feet. 

6£  feet. 

Ins. 

Lbs. 

Ins. 

Lbs. 

Ins. 

Lbs. 

Ins. 

Lbs. 

Ins. 

Lbs. 

10 

8 

18 

8 

18 

8 

18 

9 

21 

9 

21 

11 

8 

18 

9 

21 

9 

21 

9 

21 

10 

25 

12 

9 

21 

9 

21 

10 

25 

10 

25 

10 

25 

13 

10 

25 

10 

25 

10 

25 

12 

31} 

12 

31} 

14 

10 

25 

12 

31} 

12 

31} 

12 

31} 

12 

31} 

15 

12 

31} 

12 

31* 

12 

31} 

12 

31} 

12 

40 

16 

12 

311 

12 

31} 

12 

31} 

12 

40 

12 

40 

17 

12 

31} 

12 

40 

12 

40 

12 

40 

15 

42 

18 

12 

40 

12 

40 

15 

42 

15 

42 

15 

42 

19 

12 

40 

15 

42 

15 

42 

15 

42 

15 

42 

20 

15 

42 

15 

42 

15 

42 

15 

45 

15 

55 

Tie-rods,  between  the  beams,  are  required  for  any  arched 
form  of  floor,  whether  flat  or  segmental,  in  order  to  take  up  the 
arch  thrusts.  This  is  especially  true  in  the  outside  panels, 


334         FIRE    PREVENTION   AND    FIRE    PROTECTION 

where  the  thrusts  against  the  outside  framing  members  or  walls 
would  cause  spreading  unless  tie-rods  or  other  tension  members 
were  provided.  If  all  bays  of  the  floor  system  were  always 
loaded  equally,  tie-rods  would  be  theoretically  unnecessary 
(except  in  outside  bays),  as  the  thrust  of  one  arch  would  be 
counteracted  by  the  equal  thrust  of  the  adjacent  arch.  But 
varying  live  loads  make  tie-rods  necessary,  and  practical  con- 
siderations in  erection  make  them  advisable  for  almost  all  types 
of  floors. 

Tie-rods  should  line,  if  practicable,  from  beam  to  beam  for 
the  entire  floor  area.  Where  I-beams,  channels  or  girders  do 
not  occur  in  or  against  the  outside  walls,  the  tie-rods  should 
be  anchored  into  the  masonry  by  means  of  washer  plates.  Tie- 
rods  should  be  placed,  vertically,  as  near  the  line  of  thrust  of  the 
arch  as  possible.  This  is  generally  below  the  center  of  the 
beam.  One-third  the  depth  of  the  beam  up  from  the  bottom  is 
good  practice. 

In  average  practice,  tie-rods  are  not  figured,  but  are  spaced 
by  "  rule-of-thumb  "  methods,  usually  at  intervals  of  about 
eight  times  the  depth  of  the  floor  beams,  but  never  exceeding 
8  feet.  For  terra-cotta  arches  in  interior  bays  the  following 
rule  is  adequate: 

Spans  6  feet  and  under,  f-in.  diam.  rods,  5-ft.  centers. 

Spans  6  feet  to  7  feet,  J-in.  diam.  rods,  5-ft.  centers. 

Spans  7  feet  to  9  feet,  f-in.  diam.  rods,  4-ft.  centers. 

Safes.*  —  An  ordinary  office  safe  is  about  3  feet  wide,  2|  feet 
deep  and  5  feet  high,  weighing  about  3500  pounds.  Somewhat 
larger  sizes,  also  frequently  used,  weigh  about  5000  pounds. 
Reducing  these  weights  to  a  uniformly  distributed  floor  load  for 
the  area  occupied  will  give  about  450  pounds  per  square  foot. 
While  this  load  is  not  excessive,  under  proper  conditions,  for  a 
floor  arch  of  an  ultimate  capacity  of,  say,  1000  pounds  per  square 
foot  (thus  giving  a  factor  of  safety  of  two),  the  method  of  support 
is  very  important.  It  is  obvious  that  a  factor  of  safety  of  two 
under  normal  static  conditions  does  not  constitute  reasonable 
leeway  for  the  weakening  of  a  floor  arch  under  fire  test,  especially 
if  we  add  the  impact  of  falling  debris  and  the  falling  or  settling 
of  a  heavy  safe.  Yet  the  prevalent  custom  of  supporting  safes 
of  the  above  weights  on  wood  floors  and  wood  stands  or  bases 
produces  just  these  conditions  in  case  of  severe  fire.  Numerous 
*  For  further  data  regarding  portable  safes  see  Chapter  XXVII. 


FIRE-RESISTING    FLOOR   DESIGN,    ETC.  335 

fires  have  demonstrated  both  the  folly  and  the  danger  of  this 
practice.  The  damage  wrought  by  falling  safes  in  the  Equi- 
table Building  in  the  Baltimore  fire,  and  in  the  Home  Life 
Insurance  Building  fire,  has  been  described  in  Chapter  VI. 
The  report  of  Mr.  W.  C.  Robinson  on  the  Parker  Building  fire 
contained  the  following: 

The  support  of  heavy  safes  and  machinery  on  wood  floors 
and  wood  skids  in  fireproof  buildings  is  a  menace  to  both  life 
and  property,  and  should  be  absolutely  prohibited.  Heavy 
shafting  should  be  attached  to  ceilings  in  such  a  manner  that  it 
will  not  fall  as  a  result  of  fire. 

Floors  are  seldom  designed  to  withstand  the  impact  result- 
ing from  the  dropping  or  overturning  of  heavy  safes,  which  are 
often  supported  six  to  twelve  inches  above  the  floor  and  com- 
monly weigh  from  three  to  six  tons.  These  loads  should  be 
safely  distributed  by  means  of  steel  framing  resting  on  non- 
combustible  material. 

Safes  weighing  more  per  square  foot  than  one-half  the  ultimate 
capacity  of  the  floor  arch  should  be  cared  for  by  means  of  special 
supports  in  the  floor  framing. 

Insulated  Floors,  for  use  in  refrigerating  rooms,  etc.,  may 
be  made  as  follows: 

Tile  Arch.  —  Three  inches  of  matched  top  flooring,  2  layers 
building  paper,  1  inch  of  matched  sheathing,  screeds  or  sleepers 
laid  in  6  inches  of  cinder  concrete,  tile  arch  with  two  air  spaces, 
cement-plaster  ceiling. 

Concrete  Arch.  —  Two  inches  of  matched  flooring,  2  layers 
building  paper,  1  inch  matched  sheathing,  4-in.  by  4-iri.  sleep- 
ers filled  in  between  with  mineral  wool,  double  1-in.  matched 
sheathing  with  2  layers  of  paper  between,  12-in.  cinder  concrete 
slab. 

An  insulated  floor  as  used  in  a  brewery  at  Norristown,  Pa., 
is  shown  in  Fig.  50.  The  room  over  the  floor  was  under  a 
pitched  roof  and  fairly  warm,  while  the  cold  storage  room  below 
the  floor  was  kept  at  a  temperature  of  28  degrees.  No  con- 
densation has  occurred  at  the  attic-floor  level,  even  under  the 
warmest  summer  conditions. 

Waterproofing.  —  In  the  description  of  the  Roosevelt  Build- 
ing fire  in  Chapter  VI,  attention  was  called  to  the  great  damage 
done  to  stock,  etc.,  in  the  lower  stories  by  water  leaking  through 
the  various  floors  under  the  fire.  This  has  been  a  common  ex- 
perience in  fires,  showing  that,  ordinarily,  fire-resisting  buildings 


336 


FIRE    PREVENTION    AND    FIRE    PROTECTION 


TVaann  Room  under 
Pitched  Roof 


_!„„!.          ?fPlaW 

COLDSTORAGE-280 

FIG.   50.  —  Insulated  Floor  Construction. 

are  by  no  means  water-resisting.  Some  types  of  fire-resisting 
floors,  especially  those  made  of  shallow  tile  or  thin  slabs  of 
cinder  concrete,  permit  the  passage  of  water  to  such  an  extent 
as  to  make  waterproofing  absolutely  necessary  if  water  damage, 
as  well  as  fire  damage,  is  to  be  minimized;  but  even  in  those 
cases  where  the  arch  construction  is  reasonably  waterproof  in 
itself,  it  will  often  be  found  that  openings  exist  in  the  floors 
through  which  water  may  pass,  if  not  around  steam  or  other 
piping,  at  least  around  columns.  For  these  reasons,  the  water- 
proofing, by  some  means,  of  all  floors  in  fire-resisting  buildings 
is  a  necessity  which  should  be  cared  for  in  the  plans  and  specifi- 
cations. The  more  valuable  the  stock  to  be  carried  the  more 
necessity  for  adequate  waterproofing. 

The  waterproofing  of  floors  may  be  accomplished  by  using 


FIRE-RESISTING   FLOOR   DESIGN,    ETC. 


337 


an  impervious  finished  flooring,  such  as  terrazo,  or  by  using 
an  under  coating  of  tar  paper,  felt,  etc.  Specifications  of  United 
States  Government  buildings  often  require  three  layers  of  asphalt 
felt,  laid  in  hot  asphalt,  as  shown  in  Fig.  48.  The  committee 
on  fire-resisting  buildings  of  the  National  Fire  Protection  Asso- 
ciation recommended  as  follows: 

Every  floor  to  be  made  water-tight  by  a  special  surfacing 
or  stratum  impervious  to  water,  with  special  precautions  taken 
at  columns,  walls,  and  at  stair-,  pipe-,  wire-,  lighting  fixture-  or 
other  openings. 

Note.  —  This  waterproofing  to  be  completed  after  plumb- 
ers, electricians,  etc.,  have  done  their  work.  Water-tight  curbs 
at  least  12  ins.  high  are  recommended  as  additional  precautions 
at  each  floor  about  pipes,  etc.,  which  pass  through  the  floor. 

Storage  warehouses,  manufacturing  and  similar  commercial 
buildings,  especially  where  containing  valuable  stock  or  con- 
tents, should  be  provided  with 
scuppers  at  each  floor  level. 
These  should  be  placed  at  suit- 
able intervals  in  the  exterior 
walls  with  the  idea  of  carrying 
off  the  water  from  hose  streams 
or  sprinklers,  in  case  of  fire. 
Such  scuppers  should  be  made 
of  cast-iron,  the  opening  at 
floor  level  to  be  4  ins.  by  12 
ins.  in  size,  pitching  down  to 
a  4-in.  square  opening,  with  a 
flap  cover  at  the  outside  wall 
line,  as  shown  in  Fig.  51. 

Floor   Holes   for   Hose  in      Openingf 
first  or  ground  floors,  to  give    4  in.  x  12  in, 
access    for  'hose    streams   into 
basements,    are   sometimes   re- 
quired by  local  ordinances.   The 
following  ordinance  is  in  force 
in  San  Francisco: 


PLAN 
FIG.  51.  —  Scupper. 


SECTION  1.  In  order  to  enable  the  fire  department  of  the 
City  and  County  of  San  Francisco  to  promptly  reach  and  ex- 
tinguish fires  occurring  in  the  basements  of  buildings  in  said 
City  and  County,  and  which  basements  are  being  used,  or  are 
to  be  used,  for  the  storage  of  goods  or  merchandise,  without 


338 


FIRE   PREVENTION   AND    FIRE    PROTECTION 


the  loss  of  valuable  time  in  having  to  cut  holes  through  wood 
and  concrete  floors  over  such  basements  for  the  purpose  of 
gaining  access  thereto,  every  building  already  erected  and  every 
building  hereafter  erected  in  said  City  and  County,  where  the 
basement  thereof  is  being  used,  or  is  to  be  used,  for  the  storage 
of  goods  or  merchandise  of  any  description,  shall  be  provided 
with  ground  floor  pipe  casing  holes  constructed  in  and  through 
the  floor  of  the  first  story  of  such  building,  extending  down  to 


FIG.   52.  —  Ground  Floor  Pipe  Casing  for  Hose. 


and  even  with  the  basement  ceiling,  or  bottom  of  floor  joists  of 
such  first-story  floor,  so  as  to  enable  the  said  fire  department 
to  put  a  water-circulating  nozzle  through  for  the  prompt  extin- 
guishment of  any  fire  occurring  in  any  such  basement.  Such 
ground  floor  pipe  casing  holes  shall  be  constructed  according  to 
the  plan  therefor  on  file  in  the  office  of  the  Board  of  Public 
Works  of  said  City  and  County  and  shall  be  located  and  of  such 
number  as  may  be  determined  upon  by  said  Board  of  Public 
Works  after  a  consultation  held  for  the  purpose  with  the  Chief 
Engineer  of  said  fire  department  or  an  assistant  engineer  thereof, 
such  number  not  to  exceed  one  to  every  sixteen  hundred  feet  of 
floor  surface  or  part  thereof. 


FIRE-RESISTING   FLOOR   DESIGN,    ETC.  339 

SECTION  2.  No  goods  or  merchandise  of  any  description  shall 
be  stored  in  any  such  basement  in  such  manner  as  to  interfere 
with  the  proper  working  of  the  water  circulating  nozzle  used  by 
said  fire  department  which  will  pass  through  any  of  such  ground 
floor  pipe  casing  holes;  and  no  goods,  merchandise  or  any  other 
obstruction  shall  be  placed  over  the  cover  of  any  of  such  ground 
floor  pipe  casing  holes,  on  the  floor  of  the  first  story;  and  all 
such  covers  must  at  all  times  be  kept  clear  of  all  obstruction, 
so  as  not  to  interfere  with  their  prompt  use  by  said  fire  depart- 
ment in  case  of  fire. 

The  standard  pipe  casing  referred  to  in  the  above  is  illustrated 
in  Fig.  52. 

Portland,  Oregon,  and  Los  Angeles,  Cal.,  have  similar  ordi- 
nances. The  latter  requires  8-inch  pipe  inlets  in  the  ground 
floor,  spaced  every  80  feet  in  depth  of  building,  with  two  inlets 
every  80  feet  where  width  of  premises  is  more  than  50  feet. 

Cinder  Concrete  "Fill."  —  The  concrete  used  for  leveling 
up  between  beams  and  for  filling  in  between  nailing  strips  is 
often  very  defective  in  quality.  It  is  generally  termed  " filling", 
and  is  common  to  terra-cotta  floors  and  to  most  forms  of  concrete 
floors.  A  light  incombustible  mixture  of  almost  any  variety  is 
supposed  to  answer  the  purpose  of  filling  in  the  spaces  between 
the  sustaining  arch  or  slab  and  the  finished  floor,  thus  preventing 
a  free  circulation  of  hot  air  or  flame.  Its  ability  to  contribute 
materially  either  to  the  strength  of  the  arch  or  to  the  fire-re- 
sisting qualities  of  the  arch  is  not  usually  considered  a  requisite. 
The  concrete  is  rather  considered  of  secondary  importance. 
This  practice  is  decidedly  wrong,  and  poor,  weak  or  mud  mix- 
tures should  not  be  tolerated.  Much  depends  upon  the  concrete 
filling  to  protect  the  arches,  particularly  if  of  terra-cotta,  against 
sudden  blows,  and  to  distribute  properly  the  floor  loads,  as  well 
as  the  loads  resulting  from  column  casings,  partitions  or  other 
concentrated  loads.  The  concrete  is  also  valuable  as  a  means 
of  added  stiffness  in  the  floor  system.  The  lack  of  lateral  strength 
often  developed  by  poorly  constructed  hollow-tile  floor  arches 
was  commented  upon  in  the  report  of  the  engineers  appointed 
to  examine  the  Home  buildings  in  Pittsburgh,  after  the  fire  which 
destroyed  them. 

Floorings.  —  The  question  of  finished  flooring  is  largely 
dependent  upon  the  use  to  which  the  building  is  to  be  put.* 

*  Or,  sometimes,  upon  the  height.  The  New  York  Building  Law  requires 
floors  of  acceptable  incombustible  material  in  all  buildings  over  150  feet  in 
height. 


340         FIRE   PREVENTION   AND   FIRE   PROTECTION 

Heretofore,  wood  floors  have  been  used  in  almost  all  types  of 
structures  for  several  reasons,  —  because  they  have  been  the 
usual  practice,  because  they  have  been  cheap,  and  because  they 
have  generally  been  considered  pleasing  in  appearance  and  easy 
under  foot.  But,  theoretically  and  practically,  wood  floors  are 
inconsistent  with  fire-resisting  design,  and  undesirable  in  many 
ways.  They  not  only  contribute  just  so  much  combustible 
material,  but  they  serve  to  carry  fire  as  well,  especially  when 
oil-soaked,  as  is  so  common  in  factories.  On  the  other  hand,  in 
those  buildings  where  the  floors  are  much  used  by  people,  and 
where  carpeting  is  impossible,  wood  floors  are  greatly  preferred 
as  being  less  cold  and  trying  to  the  feet  than  any  substitute. 
Thus  factory  owners  find  that  their  operatives  often  complain 
of  rheumatism  and  fatigue  (especially  when  on  their  feet  a  con- 
siderable portion  of  the  time)  occasioned  by  cement  or  grano- 
lithic floors. 

While  the  general  use  of  fire-resisting  floorings  is  admittedly 
most  difficult  to  attain  in  actual  practice,  still  great  progress  has 
been  made  along  this  line  in  very  recent  years.  The  great  in- 
crease in  cement  floors  may  be  cited  as  an  example.  Formerly 
limited  to  use  in  cellars,  laundries  and  such  locations,  they  are 
now  largely  used  in  hotels,  apartment  houses,  etc.,  in  rooms  to 
be  carpeted.  Wood  nailing  strips  are  embedded  in  the  cement 
ground  around  the  perimeters  of  the  rooms,  to  which  the  carpets 
are  fastened.  This  method  is  now  very  generally  employed  in 
the  auditoriums  of  theaters,  while  in  residences  a  cement  or 
granolithic  finish  is  being  largely  used  in  closets,  etc.,  often  with 
a  cement  base,  as  an  added  protection  against  vermin. 

Types.  —  Fire-resisting  floors  include  fireproof ed  wood,  cement, 
granolithic,  terrazo,  asphalt,  monolithic,  cork  flooring,  and  marble 
or  tiling. 

Fireproofed  wood  and  monolithic  floors  are  described  in  Chap- 
ter VII. 

Cement  floors  are  usually  made  of  a  1  :  2  cement  mortar,  laid 
|  in.  or  1  in.  thick  upon  the  surface  of  the  slab  or  arch  below, 
and  troweled  to  a  hard  finish.  Such  floorings  should  always  be 
placed  upon  the  concrete  arch  or  filling  before  the  latter  has 
begun  to  set,  otherwise  no  bond  results,  and  the  flooring  will 
prove  unstable,  and  hollow  in  sound.  Cement  floors,  especially 
under  much  wear,  will  generally  prove  unsatisfactory  unless 
covered  with  carpet.  The  surface  soon  dusts  up. 


FIRE-RESISTING    FLOOR   DESIGN,    ETC.  341 

Granolithic  floors  cost  considerably  more,  when  properly  made, 
than  an  ordinary  cement  floor,  but  the  difference  is  more  than 
made  up  in  the  wearing  qualities.  A  1-inch  surfacing  of  a  mix- 
ture of  one  part  Portland  cement,  one  part  sand  and  one  part 
granite  chips  or  dust  is  laid  over  the  concrete  arch  or  filling  below, 
before  the  latter  has  begun  to  set.  This  surfacing  should  not 
be  allowed  to  set  rapidly,  but  should  be  wet  every  day  for  at  least 
a  week.  This  slow  setting  produces  an  extremely  hard  finish, 
which  reduces  dusting  to  a  minimum. 

Asphaltic  floors  are  neither  pleasing  nor  satisfactory  for  interior 
use. 

Terrazo,  made  of  marble  chips  and  cement,  and  marble-, 
encaustic-,  vitreous-,  and  ceramic- tiling  are  much  used  in  public 
buildings,  banks,  lobbies,  corridors  and  toilet  rooms,  but  are 
usually  Undesirable  in  other  locations  on  account  of  being  cold 
and  unpleasant  under  continued  use. 

Steel-woven  Oak  Flooring*  while  by  no  means  thoroughly  fire- 
resisting,  is  still  about  as  proof  against  any  ordinary  fire  and 
wrater  test  as  a  wood  flooring  can  be  made.  Hence  it  is  suitable 
for  use  in  those  buildings,  public  or  private  —  such  as  libraries, 
art  galleries,  hotels,  residences  or  office  buildings,  etc.,  —  where 
the  fire  hazard  is  comparatively  light,  but  where  wood  flooring 
is  desirable  from  the  standpoint  of  either  appearance  or  comfort. 

The  well-known  and  much  admired  English  wood-block  floor- 
ing is  usually  made  of  2-in.  by  12-in.  hard  wood  blocks,  laid 
herring-bone  pattern,  in  hot  pitch  or  asphaltum;  but  climatic 
conditions,  the  overheating  of  our  buildings  in  winter,  and  the 
usual  haste  of  our  building  operations,  have  all  contributed  to 
make  this  type  of  flooring  generally  unsuccessful  in  this  country. 
To  remedy  these  adverse  conditions,  steel-woven  oak  flooring 
is  made  of  4-inch  squares  of  hard  wood,  woven  onto  steel  bands 
which  engage  grooves  in  all  sides  of  the  blocks.  A  compression 
or  expansion  space  is  provided  at  the  borders,  so  that  changes  in 
temperature,  moisture  and  even  temporary  flooding  with  water 
will  not  affect  the  permanence  of  the  construction. 

A  very  pleasing  finish  may  be  obtained  by  using  quartered 
oak,  "sap  no  defect,"  wherein  blocks  containing  an  edging  of 
sap  are  scattered  through  the  flooring.  This  gives  an  appearance 
very  similar  to  an  old  English  oak  flooring,  though  with  markings 
on  a  larger  scale. 

*  Made  by  the  Wood-Mosaic  Company,  Inc.,  Rochester,  N.  Y. 


342         FIRE    PREVENTION    AND    FIRE    PROTECTION 

Choice  of  Flooring.  —  Suitable  floors,  from  the  standpoint  of 
fire-resistance,  may  be  selected  for  Carious  classes  of  buildings 
as  follows: 

Warehouses:   cement  or  granolithic. 

Factories  of  hazardous  tenantry:  cement  or  granolithic. 

Factories  of  light  hazard:  wood. 

Hotels:  marble  or  tile  in  lobbies,  etc.,  mosaic  or  steel-woven 
oak  flooring  in  public  rooms,  cement  in  carpeted  corridors  and 
rooms. 

Apartment  houses:  same  as  hotels. 

Theaters:  cement  covered  by  carpet. 

Schools:  cork  tile  or  linoleum. 

Office  buildings:  terrazo  in  corridors,  etc.,  monolithic  or  wood 
in  offices. 

Beam-  and  Girder-Protection.  —  The  many  failures  which 
have  resulted  in  time  of  fire  from  the  great  exposure  of  beams 
and  girders  with  insufficient  or  inefficiently  applied  protection, 
show  the  vital  necessity  of  protecting  these  members  as  carefully 
as  ingenuity  can  devise.  Girders,  especially  where  they  project 
below  the  ceiling  line,  as  is  commonly  the  case,  are  much  more 
exposed  to  the  injurious  effects  of  fire  and  water  than  the  floor 
beams.  Intense  heat  is  brought  to  bear  on  the  corners  or  ex- 
terior angles  of  girder-protections,  and  streams  from  fire  hose 
tend  to  tear  off  the  fireproofing.  The  interior  angles  also  create 
dead  air  spaces  at  these  points,  which  cause  the  flame  to  split  or 
separate,  thus  allowing  the  gathering  of  superheated  air  in  the 
interior  angles.  In  tile  construction,  this  often  vitiates  the 
cement  joints,  and  if  the  blocks  are  not  joined  mechanically  they 
are  apt  to  fall  from  position.  Also,  in  concrete  construction,  if 
the  concrete  surrounding  the  lower  portions  of  girders  is  not  of 
sufficient  thickness,  or  is  not  held  in  position  by  means  of  metal 
reinforcement,  great  damage  is  liable  to  ensue. 

Girders  usually  carry  several  or  many  floor  beams,  or  great 
concentrated  loads,  and  the  importance  of  properly  protecting 
them  must  be  in  direct  proportion  to  their  load-carrying  func- 
tions. Questions  of  cost  or  appearance  should  not  be  considered 
to  the  detriment  of  efficient  protection. 

Terra-cotta  beam-  and  girder-protections  are  described  at 
length  in  Chapter  XVII,  where  their  behavior  in  the  Baltimore 
fire  is  also  noted. 

Concrete  beam-  and  girder-protections  are  described  in  Chap- 
ter XVIII. 


FIRE-RESISTING    FLOOR   DESIGN,    ETC.  343 

Suspended  Ceilings.  —  For  all  classes  of  buildings  except 
those  of  very  heavy  construction  used  for  warehouse  purposes, 
etc.,  level  ceilings  are  preferable  for  several  reasons. 

First:  The  appearance  of  a  flush,  unbroken  ceiling  is  usually 
considered  desirable. 

Second:  A  level  ceiling  will  better  reflect  and  distribute  the 
light  from  windows. 

Third:  A  flush,  unbroken  surface  will  resist  fire  and  water  tests 
better  than  a  paneled  ceiling,  as  has  previously  been  pointed  out 
in  discussing  beam-  and  girder-protections. 

Suspended  ceilings  are  not  usually  required  in  connection  with 
terra-cotta  floor  systems,  —  unless  of  the  segmental  type  —  as 
the  arch  blocks  generally  project  bellow  the  beam  soffits,  thus 
giving  a  flush  ceiling  except  where  deep  girders  are  employed. 
Any  economical  form  of  concrete  slab  or  arch  will,  however, 
require  a  suspended  ceiling  to  give  a  flush  ceiling  surface.  This 
point  should  not  be  overlooked  in  comparing  either  the  relative 
efficiency  or  cost  of  hollow  tile  vs.  concrete  floors. 

It  has  been  shown  in  Chapter  VII  that  metal  lath  and  plaster 
constructions  may  not  be  regarded  as  fire-resistive  under  con- 
ditions approaching  any  degree  of  severity.  As  particularly 
regards  metal  lath  and  plaster  suspended  ceilings,  this  has  been 
demonstrated  in  many  fires,  notably  in  the  second  fire  in  the 
Home  Store  Building,  where  such  a  ceiling,  made  of  light  angles, 
metal  lath  and  plaster,  quickly  wilted  under  the  intense  heat 
generated  in  the  upper  story. 

It  has  also  been  shosvn,  however,  that  such  constructions  may 
be  of  decided  worth  in  protecting  the  more  valuable  and  vital 
floor  construction  above,  and  that,  while  the  ceiling  may  be  de- 
stroyed, it  may  still  fulfil  the  office  of  protecting  the  floor  slab 
or  arch  and  beam-  and  girder-protections  from  serious  injury. 
From  this  standpoint,  suspended  ceilings  are  commendable,  but 
their  positive  value  depends  entirely  upon  the  severity  of  the 
fire  test  to  which  they  are  subjected,  and,,  particularly,  to  the 
possibility  of  water  test  under  hose  streams. 

In  the  Baltimore  conflagration,  very  few  of  the  floor  arches 
in  the  several  fire-resisting  buildings  were  protected  by  sus- 
pended ceilings,  and  even  where  used,  such  ceilings  were  usually 
of  a  purely  decorative  nature,  as  in  lobbies,  etc. 

In  the  San  Francisco  buildings,  a  great  many  of  the  floor 
arches,  both  terra-cotta  and  concrete,  but  particularly  the  latter, 


344 


FIRE    PREVENTION    AND    FIRE    PROTECTION 


were  protected  by  suspended  ceilings;  and  where  the  conditions 
were  moderate,  as  in  office  buildings,  this  construction  was  gen- 
erally sufficient  to  preserve  the  integrity  of  the  floor  arches  and 
beam-protections  above. 

The  furred  ceilings  were  very  largely  a  loss.  In  buildings 
that  had  been  occupied  for  ordinary  office  purposes,  probably 
not  more  than  20  per  cent,  of  the  furred  ceilings  absolutely  came 
down;  the  remaining  80  per  cent,  stayed  in  place,  with  complete 
loss  of  the  plaster,  the  metal  furring  and  lathing,  however, 
being  in  shape  to  use  again  with  only  minor  repairs.* 

But  under  severe  conditions,  where  the  amount  of  combus- 
tible matter  was  greater  than  that  ordinarily  found  in  office 
buildings  (and  in  other  cases  where  hose  streams  have  been  used), 
the  entire  ceiling  has  generally  suffered  complete  loss.  In  such 
cases,  and  also  where  suspended  ceilings  had  not  been  used,  the 
damage  to  concrete  floors  especially  was  very  apparent  in  many 
instances.  In  fact,  Captain  Sewell  goes  so  far  as  to  state  that 
"It  would  seem  that  wherever  reinforced-concrete  floor  con- 
struction is  used,  a  furred  ceiling  below  it  should  be  absolutely 
required."  f 

The  protective  value  of  suspended  ceilings  would  be  greatly 
increased  by  making  such  construc- 
tions somewhat  heavier  than  ordi- 
nary practice,  and  by  attaching 
them  more  securely  to  the  floor  con- 
struction above.  In  many  of  the  San 
Francisco  buildings  the  light  channels 
of  the  ceiling  construction  had  been 
fastened  to  the  beams  by  means  of 
light  wire  clips,  made  of  about  No.  8 
wire,  bent  around  the  beam  flanges 
as  shown  in  Fig.  53.  These  clips 
were  quickly  heated  by  fire,  and  their 

straightening    out    soon    allowed    the 

.  ...  .  e  ,, 

entire  ceiling  construction  to  fall. 

The  use  of  copper  wire  to  secure  metal  furring  of  any  kind 
should  never  be  permitted,  as  it  will  fuse  at  a  low  temperature 
and  cause  failure.  It  was  previously  the  practice  in  United 
States  Government  buildings  to  specify  copper  wire  for  lacing 

*  Captain  John  Stephen  Sewell,  United  States  Geological  Survey  Bulletin 
No.  324,  page  72.  f  Ibid.,  page  121. 


FIG.  53.  —  Suspended  Ceiling 
Wire  Clips. 


FIRE-RESISTING   FLOOR    DESIGN,    ETC. 


345 


metal  lath  to  the  channels  of  furred  ceilings,  etc.,  but  since  the 
experience  in  the  Flood  Building  and  in  the  Post  Office  Building 
at  San  Francisco,  galvanized-iron  wire  has  been  substituted. 

The  employment  of  furred  ceilings,  no  matter  how  moderate 
the  exposure  or  how  careful  the  construction,  should  never  be 
considered  sufficient  grounds  for  omitting  efficient  beam  and 
girder  protections.  Any  such  application  of  furred  ceilings  as  is 
shown  in  Fig.  54  cannot  be  considered  even  moderately  efficient 
for  general  practice. 

Examples  of  suspended  ceilings  of  approved  construction  are 
given  in  connection  with  terra-cotta  and  concrete  floors  in  Chap- 
ters XVII  and  XVIII.  General  specifications  for  suspended 


Ceiling  Furring 
FIG.  54.  —  Objectionable  Type  of  Ceiling  Furring. 


ceilings  and  methods  employed  for  large  ceilings  under  roofs  and 
over  entire  top  stories,  etc.,  are  given  in  Chapter  XXI. 

Selection  of  Floor  Type.  —  The  choice  of  a  satisfactory 
fire-resisting  floor  type  for  any  particular  case  is  dependent  upon 
many  considerations,  but  it  will  be  found  that,  in  the  last  analysis, 
all  of  the  requirements  previously  given  as  essential  to  a  satis- 
factory type  are  dependent  upon  the  three  fundamental  factors  — 
materials,  form  and  workmanship. 

Materials  have  been  discussed  in  Chapter  VII,  and  from  data 
given  there  and  in  Chapters  XVII  and  XVIII  it  may  be  said 
that  no  decided  preference  is  to  be  accorded  either  terra-cotta 
or  concrete  floor  construction.  Good  terra-cotta  work  is  better 
than  poor  concrete  work,  and  vice  versa.  The  advantages  and 
disadvantages  of  hollow  tile  and  concrete  floors  are  pointed  out 
in  Chapters  XVII  and  XVIII  respectively. 


346         FIRE    PREVENTION    AND    FIRE    PROTECTION 

If  terra- cot ta  is  used,  the  material  should  invariably  be  porous 
or  semiporous. 

If  concrete  is  used,  almost  any  aggregate  ordinarily  employed 
will  probably  prove  satisfactory  under  moderate  fire  test,  but  for 
severe  conditions  the  question  of  aggregate  should  be  very  care- 
fully investigated.  The  corrosive  tendencies  of  cinder  concrete 
are  at  least  uncertain. 

In  either  construction,  a  good  quality  of  concrete  "fill"  is 
necessary,  for  reasons  previously  given. 

Form.  —  In  either  construction,  ample  beam-  and  girder-pro- 
tections are  always  requisite.  Level  ceilings  are  preferable  for 
reasons  previously  given,  but  suspended  ceilings  are  not  de- 
pendable except  under  moderate  conditions. 

Terra-cotta  arches  are  not  suited  to  irregular  conditions  of 
framing,  but  the  blocks  usually  project  below  the  beams,  thus 
giving  a  flush  ceiling  without  the  use  of  suspended  ceilings.  The 
blocks  should  be  of  thick  material,  with  well-rounded  fillets. 

Concrete  floors  are  well  suited  to  irregular  framing,  but  the 
strongest  form,  i.e.  segmental,  and  the  most  usual  form,  i.e.  slab 
construction,  both  require  suspended  ceilings  for  flush  finish. 
The  material  must  amply  protect  the  metal  reinforcement. 

Workmanship.  —  See  especially  Chapter  X. 

Much  terra-cotta  work  has  been  installed  very  carelessly,  even 
under  inspection. 

Concrete  also  requires  careful  supervision  as  regards  the  mix- 
ture of  ingredients,  the  position  and  quantity  of  metal  reinforce- 
ment, and  the  time  required  for  setting  before  forms  may  be 
removed. 


CHAPTER   XII. 
COLUMNS   AND   COLUMN   PROTECTIONS 

Importance  of  Column  Protection.  —  The  most  important 
load-bearing  members  in  modern  buildings  are,  without  question, 
the  columns.  Interior  columns,  which  are  here  especially  re- 
ferred to  (for  wall  columns  see  Chapter  XX),  stand  isolated  and 
exposed  on  all  sides,  but  form  the  supporting  members  for  areas 
which,  when  fully  or  even  partially  loaded,  induce  strains  of 
often  remarkable  degree;  and  in  buildings  of  great  height,  or  of 
very  heavy  loading,  the  summation  of  the  loads  in  a  column 
shaft  often  produces  strains  which  but  relatively  few  years  ago 
would  have  been  considered  extraordinary.  In  general,  it  may 
be  said  that  the  higher  the  building  the  greater  become  the 
column  loads;  but  in  special  constructions,  through  the  introduc- 
tion of  heavy  plate-  or  box-girders,  or  through  the  use  of  trusses 
to  carry  floor-  and  column-loads  over  a  clear  space  beneath, 
the  heavy  concentrated  loads  resulting  from  such  construction 
may  exceed  the  loads  found  in  even  the  highest  buildings.  In 
the  Park  Row  Building  in  New  York  city,  thirty  stories  in  height, 
the  heaviest  column  load  is  2,900,000  pounds,  while  in  the 
Waldorf-Astoria  Hotel,  of  moderate  height,  a  column  supporting 
the  large  trusses  over  the  ball-room  carries  a  load  of  5,400,000 
pounds. 

The  absolute  necessity  for  protecting  either  cast-  or  wrought- 
iron  or  steel  columns  against  fire  has  already  been  pointed  out  in 
Chapter  VII. 

The  impojtance  of  properly  fireproofing  a  column  or  structural 
member  increases  in  proportion  to  the  service  rendered  —  that 
is,  the  load  carried  —  and  also  in  proportion  to  the  exposure  to 
fire  reasonably  to  be  expected.  Thus  basement  and  lower-story 
columns  should  be  given  more  efficient  protections  than  light 
upper-story  columns,  and  buildings  or  portions  of  buildings,  where 
combustible  contents  are  liable  to  exist  in  quantity,  demand, 
particularly,  better  column  protection  than  would  naturally  be 
provided  in  buildings  containing  less  hazard. 

Experience  shows  that  these  points  are  very  often  overlooked. 
347 


348         FIRE   PREVENTION   AND   FIRE   PROTECTION 

The  steel  frame  is  carefully  designed  for  the  required  dead  and 
live  loads,  and  the  individual  members  are  accurately  pro- 
portioned for  recognized  fiber  strains  computed  by  accepted 
formulas;  but  from  this  point  on,  the  proper  fireproofing  of 
isolated  columns,  which  frequently  demand  architectural  treat- 
ment, or  a  minimizing  of  floor  space,  often  resolves  itself  into  a 
question  of  "how  little"  rather  than  "how  good."  It  is  not 
uncommon  to  find  that,  after  deducting  three-quarters  of  an 
inch  on  all  sides  for  plaster,  even  less  than  two  inches  remain 
around  important  columns  in  which  space  the  contractor  for 
fireproofing  is  expected  to  place  efficient  protection. 

Past  experience  also  emphasizes  the  folly  of  leaving  the  steel 
columns  and  roof  beams,  etc.,  unprotected  in  attics.  A  number 
of  such  instances  were  given  in  Chapter  VI,  including  both  the 
first  and  second  fires  in  the  Home  Store  Building,  and  the  Roose- 
velt Building,  to  which  should  be  added  the  National  Mechanics 
Bank  and  Calvert  Building  in  Baltimore.  This  practice  of 
neglecting  attic  spaces,  presumably  because  unseen,  has  pre- 
viously been  discussed  in  connection  with  the  first  fire  in  the 
Home  Store  Building  (see  page  140). 

Column  Failures  in  Baltimore  and  San  Francisco  Fires, 
etc.  —  In  the  Baltimore  conflagration  practically  all  the  modern 
structures  tested  by  fire  were  office  buildings,  in  which  only  two 
protected  steel  columns  failed.  The  carelessness  exhibited  in 
the  design  and  execution  of  column  protections  was,  however, 
conspicuous,  as  will  be  pointed  out  in  more  detail  later. 

In  the  San  Francisco  fire  one  of  the  greatest  faults  in  modern 
building  methods  was  shown  to  be  the  inadequate  protection  of 
steel  columns,  owing  to  the  fact  that  many  buildings  which  were 
designed  for  offices,  lofts,  or  for  light  manufacturing  occupancy, 
were  frequently  used  for  the  storage  of  large  quantities  of  com- 
bustible merchandise,  thus  causing  temperatures  of  greater 
severity  and  duration  than  existed  in  Baltimore.  Not  less  than 
50,  and  possibly  nearly  100,  failures  of  protected  columns  occurred 
in  the  San  Francisco  fire,  a  large  proportion  of  which  were  of 
basement  columns,  "indicating  that  protracted  effects  are  likely 
to  be  at  their  maximum  in  places  where  burning  material  has  its 
combustion  retarded  by  debris,"  *  — a  reason,  additional  to  that 
of  heavy  loads,  for  providing  especially  efficient  protections  for 
basement  columns. 
*  From  Report  of  S.  Albert  Reed  to  National  Board  of  Fire  Underwriters. 


COLUMNS   AND    COLUMN    PROTECTIONS  349 

A  prominent  example  of  column  failure  was  also  afforded  by 
the  Parker  Building  fire,  described  in  Chapter  VI.  The  inade- 
quate protection  provided  for  the  cast-iron  columns  in  this 
mercantile  and  light  manufacturing  building  (see  page  351)  re- 
sulted in  the  collapse  of  several  columns  arid  consequent  great 


Buildings  of  large  area  and  buildings  in  which  large  quan- 
tities of  combustible  materials  are  stored,  require  heavier  and 
more  efficient  fireproofing  than  buildings  of  moderate  area  and 
those  containing  limited  quantities  of  fuel.  The  tendency  has 
been  toward  lightness  and  cheapness,  and  fireproofing  is  often 
reduced  to  a  point  where  unsatisfactory  results  can  be  ex- 
pected.* 

Action  of  Column  Casings  in  Various  Fires.  —  Metal 
Lath  and  Plaster  Protections.  —  Single  metal  lath  and  plaster 
protections  may  suffice  in  moderate  fires  of  comparatively  short 
duration,  but  their  employment  under  severe  conditions  can  be 
considered  only  as  cheaper  substitutes  for  better  methods. 
Many  fires  have  demonstrated  the  truth  of  this.  Baltimore 
furnished  many  examples  of  the  failure  of  metal  lath  and  plaster 
partitions,  girder  coverings,  etc. 

The  summary  of  Professor  Soule  regarding  the  efficiency  of 
metal  lath  and  plaster  protections  as  exhibited  in  the  San  Fran- 
cisco fire  has  previously  been  given  in  Chapter  VII,  page  256. 
According  to  this  authority  all  lath  and  plaster  protections  were 
shown  to  be  totally  inadequate,  but  this  view,  also  held  by  Cap- 
tain Sewell,f  is  not  shared  by  other  competent  observers.  Thus 
because  lath  and  plaster  methods  failed  under  severe  conditions 
is  not  equivalent  to  saying  that  such  protections  may  not  be 
sufficient  under  less  exacting  conditions.  Mr.  Himmelwright 
states  that: 

Around  columns,  a  double  layer  of  metal  lath  and  plaster, 
next  to  concrete  and  brick,  developed  the  best  fire-resistance. 
In  all  cases  where  the  double  thickness  was  provided,  the  inner 
layer  was  unaffected  and  the  structural  members  were  satis- 
factorily protected.  Where  only  one  layer  of  wire  lath  and 
plaster  was  employed,  and  it  was  supported  by  well-executed 
steel  furring  and  anchored  to  the  columns,  it  fulfilled  the  re- 
quirements under  normal  conditions  that  prevailed  in  offices, 
hotels  and  similar  buildings.  This  method  was  not,  however, 

*  From  Report  on  Parker  Building  fire,  by  Mr.  W.  C.  Robinson  to  New 
York  Board  of  Fire  Underwriters. 

t  See  United  States  Geological  Bulletin  No.  324,  page  72. 


350         FIRE    PREVENTION    AND    FIRE    PROTECTION 

sufficient  for  the  more  severe  requirements,  and  failed  in  loca- 
tions where  fires  of  long  duration  occurred.* 

Like  suspended  ceilings,  therefore,  metal  lath  and  plaster 
column  protections  can  only  be  counted  on  for  moderate  fire- 
resistance,  and  while  their  first  cost  is  lower  than  more  efficient 
methods,  their  complete  destruction  is  to  be  expected. 

Composition  and  Plaster  of  Paris  Protections.  —  Blocks  made 
of  pure  gypsum,  or  of  various  compositions  comprising  princi- 
pally plaster  of  Paris,  are  very  low  in  conductivity,  or  heat  trans- 
mission, as  is  shown  in  the  table  of  conductivity  tests  on  page  355. 
But  such  materials  are  not  equally  satisfactory  in  their  strength 
under  high  temperatures  and  hose  streams,  as  has  previously 
been  pointed  out  in  Chapter  VII.  See  " Fire-resistance  oj 
Plaster  Blocks,"  page  258,  where  New  York  Building  Depart- 
ment tests,  and  Baltimore  fire  experiences,  etc.,  are  given. 

The  failure  of  the  plaster  blocks  used  to  protect  the  cast- 
iron  columns  in  the  Equitable  Building  was  practically  com- 
plete. The  material  crumbled  away  from  the  columns  and  fell 
to  the  floor. f 

\ 
Terra-cotta  Column  Protections .  —  Unfortunately,  much  of  the 

terra-cotta  column  protection  in  past  and  even  present  practice 
is  unworthy  of  place  in  any  building  intended  to  be  fire-resisting. 
This  detail  of  building  construction  is  a  most  pertinent  example 
of  an  excellent  material  used,  generally,  in  a  most  lamentable 
way.  It  is,  perhaps,  no  exaggeration  to  saj^  that  the  average 
example  has  been  unstable,  vulnerable  at  the  joints,  and  ineffi- 
cient to  a  degree.  A  review  of  the  fires  described  in  Chapter  VI 
will  show  that  the  terra-cotta  column  protections  were  more  or 
less  unsatisfactory  in  every  case,  —  sufficient,  generally,  to  pro- 
tect the  steel  work  from  serious  injury  —  but  almost  invariably 
damaged  themselves  to  such  an  extent  as  to  make  entire  recon- 
struction necessary.  Several  of  the  following  examples  will 
plainly  show  the  average  low  workmanship  and  inefficiency, 
which  have  contributed  to  bring  about  this  result. 

A  practical  test  of  cast-iron  columns  surrounded  by  casings 
substantially  like  that  shown  in  Fig.  63  was  afforded  by  the  fire 
in  the  Ryerson  Building,  Chicago,  August  27,  1903.  The  tile 
covering  was  of  solid  hand-made  porous  terra-cotta  blocks,  2J 

*  "The  San  Francisco  Earthquake  and  Fire,"  published  by  the  Roebling 
Construction  Company,  page  255. 

t  National  Fire  Protection  Association  Report. 


COLUMNS   AND    COLUMN    PROTECTIONS 


351 


1  Pipe 


inches  thick,  and  each  block  was  secured  to  the  iron  column  by 
means  of  a  tap  screw  having  a  washer  2  by  3  inches  in  size, 
countersunk  one  inch  into  the  terra-cotta  block,  and  covered  by 
cement.  This  detail  of  anchoring  is  very  exceptional,  but  its 
wisdom  was  amply  demon- 
strated by  the  perfect  condition 
of  the  casings,  except  for  loss  of 
plastering,  after  a  severe  test. 

In  decided  contrast  to  the 
foregoing,  Fig.  55  illustrates  the 
1-inch  shells  of  porous  terra- 
cotta, with  1-inch  air  spaces, 
used  to  protect  the  cast-iron 
columns  in  the  Parker  Building. 
The  outer  edges  of  the  cast 

brackets  or  girder  seats  on  the  columns  were  unprotected,  and 
electric  conduits  were  cut  into  the  tile  blocks,  as  shown.  The 
result  was  the  failure  of  columns,  the  collapse  of  floor  areas, 
and  the  loss  of  life  previously  described  in  Chapter  VI. 

Figs.  56*  and  57*  show  column  casings  in  the  Union  Trust  and 
Herald  Buildings,  respectively  (Baltimore  fire).     These  examples 


FIG.  55. — Column  Protection  in 
Parker  Building  Fire. 


Plaster 


1^  Tile 


FIG.  56.  — Column  Protection,  Union 
Trust  Building,  Baltimore  Fire. 


FIG.  57. — Column  Protection,  Her- 
ald Building,  Baltimore  Fire. 


are  decidedly  better  than  the  average  which  existed.  Figs.  58* 
and  59*  show,  respectively,  column  casings  in  the  Calvert  and 
Continental  Trust  Buildings,  both  of  which  are  undoubtedly 
extreme  cases  of  inefficient  work,  but  no  worse  than  many  others. 
It  is,  therefore,  no  wonder  that  the  committee  of  the  National 

*  See  National  Fire  Protection  Association's  Report  on  Baltimore  fire. 


352         FIRE    PREVENTION    AND    FIRE    PROTECTION 


Fire  Protection  Association  which  examined  these  buildings  re- 
ported that  "  hollow  terra-cot ta  tile  as  ordinarily  used  as  a  fire- 
protective  covering  for  columns  lacks  stability,  and  breaks  when 
exposed  to  heat/'*  although,  in  the  opinion  of  the  writer,  they 


Hose 
Valve 


FIG.  58.  — Column  Protection, 
Calvert  Building,  Baltimore 
Fire. 


FIG.  59.— Column  Protection,  Continental 
Trust  Company  Building,  Baltimore 
Fire. 


should  properly  have  laid  greater  stress  than  they  did  upon  poor 
details  and  workmanship,  and  less  upon  the  material  per  se. 

As  regards  terra-cotta  column  coverings  in  the  San  Francisco 
fire,  nearly  all  disinterested  investigators  agree  that  they  made 
a  very  poor  showing,  but  here,  again,  inadequate  details,  skimped 
efficiency,  and  poor  workmanship  were  prominently  in  evidence 
on  every  hand.  The  criticisms  of  Mr.  Humphrey  and  of  Pro- 
fessor Soule  regarding  inadequate  construction  as  exhibited  in 
the  San  Francisco  buildings  —  previously  quoted  in  Chapter  X 
—  applies  particularly  to  column  protection.  Captain  Sewell 
finds  that  "In  a  general  way,  practically  none  of  the  column 
protection  in  San  Francisco,  except  the  4-inch  brick  covering, 
was  adequate."  Regarding  terra-cotta  protections  especially, 
Mr.  Himmelwright f  found  that: 

The  hollow  tile  blocks  which  were  most  generally  used 
varied  considerably  in  efficiency.  Where  the  blocks  were  erected 
in  a  careful  first-class  manner,  with  good  cement  mortar  and 
anchored  to  each  other  with  metal  ties  at  the  corners,  they 
sometimes  fulfilled  the  requirements  under  normal  conditions, 
but  were  frequently  damaged  and  fell  away  from  the  columns. 

*  See  National  Fire  Protection  Association's  Report  on  Baltimore  fire, 
t  "The  San  Francisco  Earthquake  and  Fire,"  published  by  The  Roebling 
Construction  Company. 


COLUMNS  AND  COLUMN  PROTECTIONS      353 

Where  the  blocks  were  erected  in  an  indifferent  manner  the 
failures  were  very  extensive  and  resulted  in  large  damage.  In 
numerous  instances  the  bulging  of  pipes  within  the  column 
coverings  facilitated  the  failures;  the  hollow  tile  blocks  sus- 
taining more  damage  from  this  cause  than  the  other  methods. 

Concrete  Column  Protections.  —  The  application  of  concrete 
protections  to  the  exteriors  of  steel  columns  is  of  comparatively 
recent  practice,  and  while  minor  instances  have  been  recorded 
of  tests  by  fire  of  such  constructions  previous  to  the  San  Fran- 
cisco conflagration,  still  no  adequate  data  were  available.  The 
burned  San  Francisco  buildings  included  several  conspicuous 
examples  in  which  concrete  column  protections  had  been  em- 
ployed, and  it  is  generally  conceded  by  the  best  critics  that  such 
casings  were  only  exceeded  in  efficiency  by  those  made  of  brick. 
The  most  frequently  quoted  examples, are  the  following: 

The  St.  Francis  Hotel,  which  had  been  occupied  but  a  short 
time,  had  column  protections  of  cinder  concrete.  They  were 
entirely  undamaged,  but  the  building  showed  every  evidence  of 
having  suffered  only  a  moderate  fire  test. 

The  Shreve  Building  had  the  columns  in  the  lower  three  stories 
protected  by  3  inches  of  Roebling  system  of  cinder  concrete. 
They  were  unharmed,  but  the  plastering  was  generally  intact 
and  indications  pointed  to  heat  conditions  not  at  all  severe. 
In  the  upper  stories  the  columns  were  protected  by  terra-cotta 
casings,  and  the  failure  of  these  caused  the  buckling  of  several 
columns.  There  was  every  evidence  of  much  greater  heat  in 
the  upper  stories. 

The  new  eight-story  building  of  the  Pacific  States  Telephone 
and  Telegraph  Company  suffered  a  severe  fire  test,  but  the  con- 
crete column  protections  and  girder  coverings  stood  the  ordeal 
exceedingly  well.  Further  reference  to  this  column  protection 
is  made  on  page  358. 

Captain  Sewell,  however,  is  of  the  opinion  that  practically 
all  of  the  above-mentioned  cases  were  not  severe  tests  of  concrete 
coverings,  but  that  the  only  extreme  test  he  saw  was  in  the 
basement  of  the  Aronson  Building,  which  he  describes  as  follows : 

In  the  same  part  of  the  basement  as  that  in  which  the 
above-mentioned  column  was  situated  —  that  is,  under  the 
Third  street  wall  of  the  building  —  there  were  two  columns 
covered  with  cinder  concrete.  The  concrete  covering  on  one 
column  made  a  very  large  and  heavy  pier;  on  the  other  it  was 
about  4  inches  thick.  It  was  apparent  that  the  heat  in  this 


354         FIRE    PREVENTION   AND    FIRE   PROTECTION 

front  portion  of  the  room  was  not  quite  as  severe  as  it  was 
farther  back,  where  the  buckled  column  was.  Not  only  was 
there  very  much  less  evidence  of  fire  in  the  way  of  ashes,  etc., 
but  the  general  indications  pointed  to  a  considerably  lower 
temperature  —  although  the  heat  at  this  point  was  very  severe, 
nevertheless.  The  larger  cinder  concrete  pier  was  evidently 
damaged  to  some  extent  by  the  heat.  The  cement  had  appar- 
ently been  dehydrated  to  a  depth  of  one-fourth  to  three-eighths 
of  an  inch  on  the  flat  surface,  and  to  a  greater  depth  at  the 
corners.  The  other  pier  showed  more  evidence  of  intense  heat. 
It  stood  opposite  the  middle  of  the  room,  where  there  seems  to 
have  been  the  greatest  accumulation  of  combustible  matter. 
When  I  first  saw  this  column  the  cinder  concrete  was  dead  and 
friable  to  a  depth  of  nearly  an  inch.  How  much  of  this  was  due 
to  original  poor  quality  and  how  much  to  the  action  of  the  fire 
was  difficult  to  determine,  but  fire  damage  was  very  evident. 
This  pier  showed  on  the  surface  a  number  of  longitudinal  cracks 
running  from  top  to  bottom,  indicating  that  there  had  been  a 
tendency  for  the  concrete  to  fail  and  come  off  under  the  ex- 
pansion stresses.  At  a  later  inspection  a  part  of  the  concrete 
covering  of  this  column  had  been  knocked  off,  and  it  then  be- 
came apparent  that  the  cracks  above  referred  to  had  extended 
entirely  in  to  the  surface  of  the  column  itself,  and  enough  heat 
had  got  in  to  partly  burn  off  the  paint  along  the  inner  edges  of 
the  cracks.* 

From  this  test  in  the  basement  of  a  mercantile  building,  it  is 
evident  that  concrete,  at  least  around  important  members  and 
in  locations  liable  to  develop  high  temperatures,  should  be  of 
ample  thickness  and  well  tied  on,  and  that  reinforced  concrete 
requires  either  an  added  thickness  or  casing  of  concrete  for  fire 
protection  only,  or  a  protective  covering  of  some  other  material, 
as  previously  described  in  Chapter  VII. 

Brick  Column  Protections.  —  Well-burned  ordinary  brick 
of  good  quality,  properly  laid  in  cement  mortar,  is  the  best 
material  now  in  use  as  a  fire-protective  covering  for  steel  or  iron 
columns.  This  material  combines  rigid  construction  and  the 
necessary  fire-resistive  qualities.! 

The  Baltimore  experience,  referred  to  in  this  opinion,  offered 
no  comparison  between  concrete  and  brick  column  protections, 
but  of  the  San  Francisco  fire,  where  both  methods  were  tested 
practically  side  by  side,  the  same  opinion  as  the  above  is  held 
by  many  careful  observers.  Thus  the  committee  of  the  American 

*  See  United  States  Geological  Bulletin  No.  324,  page  79. 
f  Report  of  National  Fire  Protection  Association  on  Baltimore  fire,  page 
119, 


COLUMNS  AND  COLUMN  PROTECTIONS 


355 


Society  of  Civil  Engineers  stated  that  "For  columns,  the  fire- 
proofing  that  will  stand  up  best  is  red  brick  set  in  Portland  cement 
mortar."* 

Most  of  the  brick  column  protections,  however,  were  of  wall 
columns,  which  are  more  particularly  discussed  in  Chapter  XX. 

Conductivity  of  Materials.  —  In  addition  to  the  data  given 
in  Chapter  VII,  the  following  tablet  is  of  value  as  showing  the 
Iheat  conductivity  of  various  materials  used  for  column  protec- 
tions. The  tests  summarized  in  this  table  were  made  by  the 
.Bureau  of  Buildings  of  New  York  City,  by  placing  the  different 
materials  on  a  cast-iron  plate  which  was  subjected  to  a  tempera- 
Iture  of  1700°  F.  for  two  hours.  The  temperatures  at  the  back 
jof  the  plate  were  then  noted  at  regular  intervals. 


Temperature   of   plate   at 

back  of   protective  ma- 

terial.    (Degrees  Fahr.) 

Tempera- 

ture on 

Material. 

face  of 
protec- 
tive ma- 
terial. 

Before 
heating. 

After 
heating 
2  hours. 

Heat 
trans- 
mission. 
Deg.  F. 

De-y.  F. 

Terra-cotta,  dense,  hollow,  2  in.  thick  

1700 

75 

223 

148 

Terra-cotta,  semi-porous,  solid,  2  in.  thick.  .  . 

1700 

73 

244 

171 

Plaster  of  Paris  and  shavings,  2  in.  thick  — 

1700 

69 

159 

90 

Blaster  of  Paris  and  asbestos,  2  in.  thick.  .  .  . 

1700 

70 

163 

93 

Plaster  of  Paris,  wood  fibres,  and  infusorial 

earth,  2  in.  thick  

1700             72 

167 

95 

Concrete  of  ground  cinders,  Ij5g  in.  thick  

1700             73 

363 

290 

Cinder  concrete,  on  metal  lath,  2  in.  thick.  . 

1700 

66 

248 

182 

Metal  lath  and  patent  plaster,   5   in.  thick 

over  1  inch  air-space  

1700 

76 

296 

220 

Essentials  for  Column  Protections.  —  From  the  foregoing 
practical  tests  of  column  protections  in  actual  fires,  it  would 
appear  that  the  requisites  for  acceptable  column  coverings  are: 

1.  Resistance  to  fire  or  water,  or  the  combined  action  of  both. 

2.  Non-conductivity  of  heat. 

3.  Permanency  of  position,  so  that  the  covering  cannot  be 
dislodged  by  fire,  water  or  debris. 

4.  Invulnerability  at  the  joints. 

*  Trans.  Am.  Soc.  C.  E.,  Vol.  LIX,  page  242. 

t  Mr.  Rudolph  P.  Miller,  Superintendent  of  Buildings  in  New  York  City, 
in  Kidder's  "Architects'  and  Builders'  Pocket-book",  page  740. 


356         FIRE    PREVENTION    AND    FIRE    PROTECTION 

5.  Adequacy,  or  thickness,  to  withstand  the  worst  conditions 
to  be  expected. 

6.  Good  workmanship. 

The  material  must  be  adapted  to  resist  both  fire  and  water, 
or  alternate  attacks  from  both,  and  this  with  as  little  reconstruc- 
tion afterwards  as  possible.  If  the  capacity  for  long  resistance 
to  fire  is  to  be  developed,  or  if  the  member  is  an  important  one 
in  the  structural  design,  two  thicknesses  of  any  material  placed 
in  block  form  (save  possibly  brick),  should  be  used,  the  different 
layers  breaking  joints.  The  material  employed  must  also  be 
non-heat-conducting,  so  as  to  protect  the  metal  work  against 
undesirable  expansion. 

The  casing  must  also  be  so  built  as  to  withstand  fire  and  hcse 
streams  without  dislodgment.  The  construction  must,  there- 
fore, be  entirely  independent  of  any  combustible  material.  It 
should  be  continuous  from  the  floor  arch  to  the  ceiling,  rest- 
ing firmly  and  directly  on  the  fire-resisting  floor,  and  not  on 
wooden  flooring  or  on  wooden  screeds,  as  has  been  so  often  done. 
Stability  also  requires  that  all  column  protections,  of  whatever 
material,  be  securely  anchored  to  the  columns,  preferably  every 
12  to  18  inches  in  height.  This  is  to  protect  the  construction 
against  the  expansion  of  the  steel  column,  against  unequal  ex- 
pansion in  the  covering,  and  against  falling  debris.  It  may  be 
accomplished  in  concrete  or  brick  casings  by  means  of  embedded 
anchors  or  clips  attached  to  the  columns,  and  in  torra-cotta  or 
plaster  of  Paris  protections  by  means  of  galvanized-iron  wire 
bound  around  each  course  of  blocks.  Copper  wire  should  not 
be  used  on  account  of  its  low  fusing  temperature. 

Column  protections  should  also  be  built  entirely  independent 
of  partitions,  so  that  the  failure  of  the  latter  may  in  no  wise 
destroy  the  integrity  of  the  former.  Many  fires  have  shown  that 
where  partitions  are  a  part  of  or  bonded  into  the  column  casings, 
the  result  has  almost  always  exposed  the  column.  Finally,  good 
workmanship  is  essential,  not  only  to  insure  the  fire-resisting 
qualities  intended,  but  also  to  prevent  the  possibilities  of  corro- 
sion which  attend  imperfect  work. 

The  ingenuity  and  thought  expended  upon  new  types  of 
floor  construction,  all  of  which  at  least  aim  to  protect  the  floor 
beams,  have  not  been  paralleled  by  equal  improvements  in  the 
question  of  column  fireproofing.  Many  of  the  companies  which 
furnish  and  erect  patent  floor  constructions  also  have  their  own 


COLUMNS   AND    COLUMN   PROTECTIONS  357 

system  of  column  protection,  but  the  attention  of  the  architect 
is  principally  engaged  by  the  merits  of  the  floor,  and  the  accom- 
panying column  protection  is  often  accepted  with  the  type  of 
floor  selected.  A  construction  company  may  control  a  most 
commendable  type  of  fire-resisting  floor,  .while  the  system  of 
column  casing  employed  by  the  same  company  may  be  poor  in 
the  extreme.  There  can  be  no  excuse  for  linking  one  with  the 
other. 

No  part  of  a  steel  building  requires  more  attention  as  to  fire- 
proofing  than  the  columns,  and  absolutely  no  considerations  of 
appearance  or  question  of  floor  space  occupied  should  be  allowed 
to  influence  unduly  the  shape  or  size  of  the  fireproofing  material. 

Solid  vs.  Hollow  Column  Casings.  —  During  the  earlier 
stages  of  fireproofing  it  was  generally  considered  advisable,  in 
:he  protection  of  steel  members,  to  provide  air-spaces  to  act  as 
leat  insulation.  This  was  accomplished  by  making  the  pro- 
tection a  mere  free-standing  circular  or  rectangular  shell  around 
the  column,  or  by  using  blocks  kept  away  from  the  column  shaft 
by  return  flanges  (as  in  Fig.  55),  or  by  furring  out  metal  lath  and 
plaster  construction.  Such  practices  are  open  to  many  objec- 
tions. First,  stability  under  fire,  hose  streams  and  falling  debris, 
requires  that  the  casing  be  rigid,  and  impossible  of  deformation 
by  pushing  inwards.  Second,  the  stiffening  effect  of  solid  casings 
upon  the  enclosed  steel  members  is  only  beginning  to  be  properly 
realized.  Third,  hollow  casings  always  mean  the  possibility  of 
there  being  vertical  flues  of  two  or  more  stories  in  height  within 
such  casings,  owing  to  possible  holes  in  the  floor  construction 
within  the  casing  perimeter.  Fourth,  and  by  no  means  least, 
hollow  casings  do  not  provide  the  protection  to  the  metal  columns 
against  dampness  or  other  corrosive  influences  which  is  secured 
by  thoroughly  surrounding  the  column  with,  for  instance,  cement 
mortar.  This  last  consideration  is  touched  upon  at  greater 
length  on  page  365,  and  also  in  Chapter  VIII. 

The  following  observations  on  the  San  Francisco  fire  are  of 
particular  interest  in  this  connection: 

Air-space  coverings  of  plaster  or  cement  on  metal  webbing 
did  fairly  well,  though  several  authenticated  cases  of  column 
failure  occurred  with  such  covering.  The  best  results,  how- 
ever, were  shown  by  solid  concrete  column  covering  without  air- 
space, the  concrete  being  reinforced  by  metal  webbing.  It  is 
probable  that  the  air-space  idea  will  be  in  less  repute  in  all 
future  efforts  to  armor  structural  steel.  It  has  been  shown  to 


358         FIRE    PREVENTION   AND    FIRE    PROTECTION 

be  largely  fallacious  in  practice.  The  results  in  the  Bush  Street 
Telephone  Exchange  may  be  considered  fairly  decisive  as  to 
solid  concrete  column  protection.  The  temperatures  in  this 
building  were  not  only  extreme,  but  were  also  .  protracted. 
Even  a  quantity  of  wire  nails  was  found  welded  into  a  mass; 
yet  the  column  protection  appeared  to  be  perfect.  The  bracing 
effect  of  the  solid  concrete  encasing  the  steel  column  is  doubt- 
less an  important  factor,  and  it  is  probable  that  with  such  rein- 
forcement the  steel  might  even  attain  a  softening  temperature 
without  deflection.* 

The  columns  in  the  James  Flood  Building  were  Z-bar  col- 
umns and  were  filled  in  solidly  with  brickwork,  in  addition  to 
the  hollow  tile  covering.  In  my  judgment,  this  construction 
was  the  only  thing  that  saved  the  Market  street  wing  of  this 
building  from  collapse,  because  there  was  every  evidence  that 
the  columns  which  were  found  slightly  buckled  had  reached  a 
dangerous  temperature,  and  would  probably  have  come  down 
and  wrecked  all  of  the  building  above  them  had  it  not  been 
for  the  stiffening  effect  of  the  brick  filling,  f 

Therefore,  to  insure  the  most  perfect  protection  to  the  column, 
the  casing  form  should  be  built  out  solid  to  some  regular  outline, 
with  either  terra-cotta,  concrete  or  brick,  outside  of  which 
should  be  placed  the  .final  protective  casing  and  the  plastering  or 
other  finish. 

Inasmuch  as  the  base  of  the  casing,  near  the  floor,  is  liable 
to  be  surrounded  by  water  from  hose  streams,  etc.,  it  has  been 
suggested  J  to  place  a  solid  concrete  base  around  the  column, 
extending  say  6  inches  above  the  finished  floor,  on  which  the 
casing  should  rest. 

Required  Thickness  of  Column  Protections.  —  Assuming 
that  solid  column  casings  are  used,  as  described  in  the  preceding 
paragraph,  the  following  thicknesses  of  materials  outside  of  the 
boldest  point  of  metal  work  are  to  be  recommended  for  efficient 
protection,  open  spaces  of  columns  always  filled: 

Metal  lath  and  plaster,  —  single  thickness,  questionable  for 
even  lightest  hazard;  double  thickness  and  air-space  for  condi- 
tions of  ordinary  hazard. 

Plaster  of  Paris  or  composition  blocks,  wired,  —  3-inch  hollow 
or  solid  for  ordinary  conditions;  use  questionable  for  severe 
conditions. 

*  From  report  of  Mr.  Albert  S.  Reed  to  National  Board  of  Fire  Under- 
writers. 

t  Bulletin  324  of  United  States  Geological  Survey,  Captain  John  Stephen 
Sewell,  page  92. 

t  See  Mr.  Coryclon  T.  Purdy,  in  Fireproof  Mayazine,  March,  1904,  page  33. 


COLUMNS  AND  COLUMN  PROTECTIONS      359 

Porous  terra-cotta,  wired, — 3-inch  blocks  for  light  hazards; 
4-inch  blocks  for  ordinary  conditions,  preferably  in  two  layers. 

Concrete,  anchored,  or  with  metal  lath  embedded  therein,  — 
3  inches  for  light  hazard  buildings,  such  as  hotels,  office  build- 
ings, etc.;  4  inches  for  stores;  6  inches  to  8  inches  in  dangerous 
risks.  2  inches  to  3  inches  of  concrete  if  covered  with  3  inches  of 
terra-cotta. 

Brick,  anchored, — 4-inch  casing  for  ordinary  conditions; 
6-inch  to  8-inch  casings  for  severe  conditions. 

Protections  must,  of  course,  at  least  equal  the  requirements 
of  local  building  laws. 

Types  of  Column  Protections  in  Current  Practice.— 
Types  of  column  protections  in  common  use  are  those  previously 
enumerated  in  the  discussion  concerning  fire-resistance,  namely, 
metal  lath  and  plaster,  plaster  of  Paris  or  composition  blocks, 
terra-cotta,  concrete,  and  brick.  Ordinary  forms  of  these  pro- 
tections will  now  be  described. 

Metal  Lath  and  Plaster  Protection.  —  Stiffened  wire  net- 
ting, Bostwick  lath,  and  expanded  metal  lath  are  extensively 
used  with  plaster  coatings  as  a  means  of  column  protection. 

In  many  instances  the  column,  especially  if  circular  in  form, 
is  simply  wrapped  close  with  metal  lath,  and  plaster  is  then  ap- 
plied without  any  intervening  air-space.  This  practice  should 
particularly  be  avoided,  as  the  close  wrapping  of  the  metal  lath 
does  not  leave  sufficient  room  for  a  key  to  the  plaster  on  the 
under  side.  The  plaster  will  soon 
fall  off  under  the  action  of  fire  or 
water. 

A  better  method  is  to  use  some 
form  of  furring  strips  to  separate 
the  lath  and  plaster  from  the 
column,  as  shown  in  Fig.  60. 
Furring  strips  to  which  the  wire 
netting  or  lath  is  wired  are  often 
made  of  small  V-shaped  pieces  of 
sheet-iron,  placed  in  a  vertical 
position  around  the  column.  A  FlG-  60. -Single  Metal  Lath  and 

..,,,.          ,.        .  .    .      .     ^  .  Plaster  Column  Protection. 

still  better  furring  strip  is  Berger  s 

economy  stud,  shown  in  Fig.  60,  as  the  metal  lath  or  expanded 

metal  can  then  be  easily  applied  and  fastened  without  wiring. 

For  rectangular  columns,  the  furring  studs  may  be  attached 


360         FIRE    PREVENTION    AND    FIRE    PROTECTION 

to  light  bars  or  channels,  clamped  around  the  column,  as  shown 
in  Fig.  61. 

The  best  method  of  column  protection  by  means  of  plaster 
is  through  the  use  of  a  double  wrapping,  with  intervening  air- 
spaces, as  in  Fig.  62.  Metal  lath  is  first  wrapped  around  furring 
strips  placed  next  the  column,  and  securely  wired  at  the  lap. 


FIG.  6 1.  —  Single  Metal  Lath  and  Plaster        FIG.  62.  —Double  Metal  Lath  and 
Column  Protection.  Plaster  Column  Protection. 

After  a  heavy  coat  of  hard  mortar  has  been  applied  to  this 
wrapping,  a  second  set  of  furring  strips  and  lathing  is  applied, 
finished  with  one  or  two  rough  coats,  preferably  cement  plaster, 
and  a  finished  coat.  This  is  much  to  be  preferred  to  any  cheaper 
form  of  metal  lath  and  plaster  protection,  but  will  cost  little, 
if  any,  less  than  a  still  more  efficient  covering  of  solid  concrete. 

All  of  these  hollow  metal  lath  and  plaster  types  are  objection- 
able from  the  standpoint  of  protection  against  corrosion,  as  the 
metal  work  is  not  directly  covered. 

Plaster  Block  Column  Casings  are  usually  made  of  the 
same  blocks  of  gypsum  or  plaster  of  Paris  as  are  employed  in 
partition  construction,  and  such  protections  are  no  more  reliable 
than  partitions  made  of  the  same  material  (see  Chapter  VII, 
page  258).  The  low  conductivity  of  the  material  is  more  than 
offset  by  its  disintegration  under  heat  and  water. 

TERRA-COTTA  COLUMN  CASINGS. 

Cast-iron  Columns,  Circular  Finish.  —  The  desire  to 
economize  floor  space,  or  to  secure  some  particular  architectural 
effect,  often  tempts  architects  to  call  for  very  thin  solid  slabs,  so 
that,  for  instance,  an  8-inch  circular  cast-iron  column  may  finish, 
when  plastered,  not  over  12  inches  diameter.  This  requires 


COLUMNS  AND  COLUMN  PROTECTIONS 


361 


blocks  of  about  1-inch  thickness,  but  the  use  of  such  tiles 
should  never  be  permitted.  They  are  too  thin  to  form  even 
passably  good  protection,  and  it  is  impracticable  to  manufacture 
them  successfully.  They  must  be  dried  over  a  drum,  and  in 
doing  this  the  shrinkage  causes  them  to  crack  through  the  center, 
unless  the  pieces  are  made  very  small,  in  which  case  the  setting 
becomes  impracticable. 


FIG.  63.  —  Circular  Terra-Cotta  Column 
Protection. 


FIG.  64.  —  Circular  Terra-Cotta 
Column  Protection. 


The  more  common  types  of  circular  protections  for  cast-iron 
columns  are  illustrated  in  Figs.  63,  64  and  65.     All  of  these  forms 


FIG.  65.  —Circular  Terra-Cotta  Column  Protection. 

are  made  up  of  segments,  shaped  to  required  radii,  either  with 
or  without  air-spaces  as  shown.  The  outer  surfaces  of  all  tile 
are  scored  or  grooved  to  provide  a  bond  for  the  plastering.  The 
blocks  are  laid  in  layers  or  courses,  and  although  many  protec- 
tions of  this  type  are  used  without  any  tying  together  other  than 
the  mortar  joints  and  backing,  each  course  should  preferably  be 
wound  with  wire  as  before  described.  All  vertical  joints  should 
be  staggered. 


362 


FIRE    PREVENTION   AND    FIRE    PROTECTION 


Steel  Columns,  Circular  Finish.  —  A  common  form  is  as 
shown  in  Fig.  66,  but  unless  the  column  is  shaped  out  solid  by 


FIG.  66.— Circular  Terra-Cotta 
Column  Protection. 


FIG.  67. —  Circular  Terra-Cotta    and 
Concrete  Column  Protection. 


means  of  concrete,  or  additional  terra-cotta  blocks,  so  as  to  give 
a  circular  form  before  the  casing  is  placed,  the  construction  is 
unstable  and  unsatisfactory  from  every  view-point.  The  hollow 
casing  gives  no  protection  to  the  column  against  corrosion. 
Much  more  satisfactory  combination  casings  of  concrete  and 
terra-cotta  are  shown  in  Figs.  67  and  89. 

Fig.  68  illustrates  a  circular  casing  for  plate  and  channel  column 
as  used  in  the  Adams  Building,  Chicago,  1904,  Holabird  and 


FIG.  68.  —  Column  Protection,  Adams  Building,  Chicago.  —  Holabird  &  Roche, 
Architects. 

Roche,  architects,  and  Fig.  69  shows  a  similar  casing  as  used  in 
the  New  York  Life  BuilJing,  Chicago,  Jenney  and  Mundie, 
architects.  In  the  ktter  case  each  tile  was  clamped  to  those 


COLUMNS  AND  COLUMN  PROTECTIONS 


363 


above  and  below,  'as  well  as  around  the  column.  The  blocks 
were  set  in  mortar  made  of  1  part  Portland  cement  to  3  parts 
best  lime  mortar. 


FIG.  69.— Column  Protection,  New  York        FIG.  70.  —  Rectangular  Terra-Gotta 
Life    Building,    Chicago.  — Jenney  Column  Protection. 

&  Mundie,  Architects. 

Cast-iron  Columns,  Rectangular  Finish.  —  The  most 
common  method  is  to  use  3-inch  partition  blocks,  laid  up  to  give 
the  required  outside  dimensions,  as  in  Fig.  70.  Various  thick- 
nesses of  blocks  are  used,  3  inches  being  about  average  practice, 
but  4  inches  is  preferable  as  before  stated.  The  blocks  should 
be  set  so  that  the  vertical  joints  alternate  in  the  successive 
courses.  This  is  usually  considered  to  give  sufficient  bond  to 
hold  the  blocks  in  position,  but  for  efficient  work,  binding  with 
wire  is  essential.  A  more  efficient  casing  would  be  obtained  by 
first  covering  the  column  with  metal  lathing  and  a  cement  plas- 
ter, and  then  applying  the  tile. 


FIG.  71.  —  Rectangular  Terra-Cotta 
Column  Protection. 


H, 


FIG.  72.  —  Rectangular  Terra-Cotta 
Column  Protection. 


ctangular  columns  are  often  finished  with  quartered  or 
rounded  _corners,  as  shown  in  Fig.  71. 


364 


FIRE    PREVENTION    AND    FIRE    PROTECTION 


Steel  Columns,  Rectangular  Finish.  —  The  more  common 
forms  are  shown  in  Figs.  72  and  73,  which  illustrate  square  and 


Cinder  Concrete 

FIG.  73.—  Rectangular  Terra-Cotta 
Column  Protection. 


FIG.  74.  —  Rectangular  Terra-Cotta 
Column  Protection. 


quartered  corners  respectively.  The  blocks  employed  are  from 
2  inches  to  4  inches  in  thickness,  and  have  usually  been  placed 
without  backing.  Old  brick  or  other  refuse  material  is  often 
filled  in  behind  the  casing  to  block  it  out  and  steady  it  while 
being  set.  Careless  blocking  in  this  manner  should  not  be  per- 
mitted, but  an  arbitrary  rule  should  be  established  requiring  a 
careful  and  solid  filling  behind  all  column  casings.  Other  ordi- 
nary types  are  shown  in  Fig.  74,  a  light  plate  and  angle  column, 
and  in  Fig.  75,  a  "Gray"  column. 


FIG.  75.  —  Rectangular  Terra-Cotla 
Column  Protection. 


FIG.  76. —Column  Protection, 
"The  Fair"  Building,  Chicago. 
Jenney  &  Mundie,  Architects. 


A  commendable  double  casing  is  illustrated  in  Fig.  76.  '  This 
detail  was  used  in  "The  Fair"  retail  store  building,  Chicago, 


COLUMNS  AND  COLUMN  PROTECTIONS 


365 


Jenney  and  Mundie,  architects.  In  case  the  outer  layer  is  dam- 
aged or  displaced,  the  column  still  has  the  protection  of  the  inner 
blocks.  A  similar  detail  was  also  used  for  circular  columns,  in 
which  case  the  inner  layer  was  bound  in  place  by  either  wires 
or  wire  netting. 

Typical  column  protections  used  in  the  new  Chicago  Post  Office 
Building  are  illustrated  in  Fig.  77.* 


FIG.  77.  — Column  Protections,  Chicago  Post  Office. 

Outside,  the  columns  were  treated  as  follows:  The  rust, 
wherever  there  .was  any,  was  thoroughly  scraped  off  and  the 
entire  surface  carefully  plastered  with  a  rich  coating  of  Portland 
cement.  .  .  . 

After  this  thorough  plastering,  the  channels  of  all  the 
column  sections  were  filled  up  with  tile  and  slab  tiles  placed 
outside  where  necessary  to  make  up  for  rivet  heads,  and  then  a 
furring  wall  of  three-  or  four-inch  partition  tiles,  as  the  case 
might  be,  was  built  about  the  column  to  form  a  perfect  square. 
The  joints  were  not  clipped  or  held  together  in  the  usual  way 
with  galvanized  iron  "  clothespins/'  but,  at  Mr.  E.  V.  John- 
son's suggestion,  a  strip  of  metal  fabric,  the  full  width  of  the 
tile,  was  laid  in  each  horizontal  joint  and  well  lapped  at  the 
ends.  Mortar  was  bedded  upon  this,  and  the  next  layer  or 
course  was  built,  more  metal  fabric,  and  so  on  up  all  the  way. 
At  every  three  or  four  feet  a  grouting  of  cement  would  be  poured 
in  back  of  the  furring,  so  that  all  the  little  interstices  between 
metal  and  tile  were  sure  to  be  filled,  and  the  greatest  of  care 
was  taken  at  the  finishing  up  of  the  top  juncture  with  the  beams, 
that  all  the  steel  should  be  abundantly  covered  with  cement 
and  tile  fireproofing.* 

*  See  F.  W.  Fitzpatrick,  formerly  Superintendent  of  Chicago  P.  O.  Building, 
Fireproof  Magazine,  December,  1903.  f  Ibid. 


366 


FIRE    PREVENTION    AND    FIRE    PROTECTION 


Special  Terra-cotta  Column  Coverings.  —  From  consid- 
erations of  architectural  treatment,  special  shaped  casings  are 
often  desired,  as  indicated  in  Figs.  78  and  79.  Casings  of  un- 
usual form  are  generally  worked  out  by  the  manufacturers  in  the 


FIG.  78. — Octagonal  Column  Pro- 
tection. 


FIG.  79. —  Special  Column  Protec- 
tion. 


most  practical  way,  but  as  they  do  not  usually  receive  any  special 
study,  and  as  the  opportunity  of  securing  knowledge  from  ex- 
perience is  lacking,  their  practical  value  is  greatly  lessened.  For 
the  best  work,  it  is  advisable  to  adhere  to  the  most  simple  and 
reliable  forms. 

The  practice  of  placing  piping  within  column  coverings  is 
discussed  in  a  later  paragraph. 

United  States  Government  Practice.  —  The  following 
specifications  are  used  in  United  States  Government  buildings 
where  terra-cotta  column  coverings  are  required: 

Terra-cotta  Column  Covering.  —  Where  terra-cotta  is  indi- 
cated, the  covering  of  columns  shall  be  at  least  3  inches  thick. 
There  shall  be  also  in  each  horizontal  joint  continuous  strips  of 
f-inch  mesh  No.  16  gauge  galvanized  wire  netting,  which  shall 
be  lapped  at  all  corners.  Blocks  shall  have  not  less  than  three 
cells,  with  not  less  than  f-inch  thick  shells  and  webs. 

Concrete  Column  Casings.  —  The  practice  of  using  solid 
concrete  casings  has  undoubtedly  been  greatly  stimulated  by 
the  record  of  such  coverings  in  the  San  Francisco  fire,  not  only 
on  account  of  the  admirable  fire-resistance  offered,  but  also  on 
account  of  the  added  stiffness  or  support  given  to  the  steel  mem- 
bers embedded  therein,  as  previously  descirbed.  However,  if 
cinder  concrete  is  used,  great  care  is  necessary  regarding  the 


COLUMNS   AND    COLUMN   PROTECTIONS 


367 


quality  of  cinders,  and  regarding  the  mixing  and  method  of 
placing.  Great  diversity  cf  opinion  exists  concerning  the  cor- 
rosive tendencies  of  cinder  concrete,  as  has  previously  been 
pointed  out. 

Concrete  casings  should  either  be  anchored  to  the  steel  columns 
or  have  an  embedded  and  lap-laced  reinforcement  in  the  shape 
of  wire  netting  or  expanded  metal. 

In  the  Druecker  warehouses,  Chicago,  built  in  1898,  the  col- 
umns were  fireproof ed  as  follows.*  A  concrete  composed  of  1 
part  cement,  1  part  lime  putty  and  4  parts  cinders  was  well 
rammed  into  wooden  forms  placed  around  the  columns.  These 
forms  were  cylindrical  in  shape,  made  of  2-inch  staves,  and  in 
sections  4  feet  long.  They  were  hinged  to  open  in  the  direction 
of  their  length  (see  Fig.  80).  The  concrete  was  poured  in  place 


, 


Fig.  80.  —  Forms  for  Circular  Concrete  Column  Protection. 


from  the  top,  and  was  well  rammed,  so  as  to  fill  completely  the 
inner  cavities  of  the  columns,  as  well  as  to  surround  them  entirely. 
As  soon  as  one  4-foot  section  was  concreted,  a  second  section  was 
constructed  on  top  of  the  first,  and  this  process  was  continued  to 
the  top  of  the  column,  before  the  floor  was  placed.  This  insured 
a  continuous  envelope  to  the  column,  without  joint  from  base- 
ment to  roof.  The  metal  columns  were  not  painted,  but  were 
simply  cleaned  of  mill  scale  and  other  foreign  substances  at  the 
building  before  the  concreting  was  started.  After  the  floors 
were  laid,  the  concrete  column  protections  were  covered  with 
metal  lath,  on  which  was  placed  a  thick  coat  of  dense  hard  mortar. 
The  metal  lath  was  used  to  provide  a  better  key  for  the  mortar 
finish. 


*  See  "Fireproofing  of  Warehouses,"  by  Frank  B.  Abbott,  Journal  of  the 
West.  Soc.  of  Engrs.,  April,  1898. 


368         FIRE    PREVENTION    AND    FIRE    PROTECTION 

Fig.  81  shows  the  detail  of  column  protection  employed  ii 
the  United  States  Appraisers'  Warehouse,  New  York  City.     Th 


—Column 


—Wire 


Fig.  81.  — Concrete  Column  Protection,  U.S.  Appraisers'  Warehouse,  N.Y. 

columns,  which  are  cast-iron  in  the  basement  and  lower  stories 
and  Z-form  in  the  upper  stories,  are  surrounded  by  an  envelope 
of  No.  24  expanded  metal,  2J-inch 
mesh,  enclosing  an  air  jacket.  This 
envelope  received  on  its  outer  surface 
a  2-inch  layer  of  fine  concrete  made 
of  1  part  American  Portland  cement, 
2  parts  sand  and  4  parts  f-inch  broken 
stone,  the  outer  surface  of  which  was 
finished  with  a  J-inch  protective  coat 
of  asbestic  plaster. 

The  following  type  of  concrete  col- 
umn casings  was  used  in  the  two 
buildings  of  the  Pacific  States  Tel.  & 
Tel.  Co.  (main  building  referred  to  by 
Mr.  Reed  on  page  358),  the  Cali- 
fornia Casket  Company's  building, 
and  the  St.  Francis  Hotel,  all  in  San 
Francisco:  "The  concrete  column 

FIG.    82.  — Concrete    Column  protection   was    anchored    to    the    col- 
Coverings  used  in  San  Fran-    umns  by  means  of  No.  10  gauge  gal- 
cisco  Buildings.  vanized-steel     wire     wound     spirally 

around  them  at  12  to  14  inches  centers.     The  wire  is  sufficiently 
stiff  to  spring  away  from  the  plates  or  flat  sides  of  the  column, 


COLUMNS  AND  COLUMN  PROTECTIONS 


369 


and  affords  a  key  for  the  concrete  between  the  steel  member  and 
the  wire."*     (See  Fig.  82.) 

Concrete  column  casings  as  used  in  the  United  States  Post 
Office  and  Court  House  at  Spokane,  Wash.,  are  shown  in  Fig.  83. 


/Wood  Form 


Wire  Loops  12  cts. 

FIG.  83  —  Concrete  Column  Casings,  U.S.  Post  Office  and  Court  House, 
Spokane,  Washington. 

The  forms  were  made  of  rough  boards,  in  sections  not  more  than 
12  inches  high.  A  clinker  concrete  of  a  1  :  2J  :  5  mixture  was 
used,  fairly  wet,  and  thor- 
oughly tamped  as  each  sec- 
tion of  form  was  placed. 
Loops  of  j-inch  galvanized 
iron  wire,  with  the  ends 
locked  as  indicated,  were 
laid  in  the  forms  as  the  con- 
crete was  brought  up  to  the 
top  of  each  section. 

Brick  Column  Casings. 
—  One  of  the  best  examples 
of    brick    casings    for 
standing  columns  is  in    the 
new     government      Printing 
Office  building,  Washington,  D.  C. 
column   protection. 


Qoncretc 


Porous  Bricks  . 

free-  FlG>  84'  — Brick   Column   Casings,  U.S. 
Government  Printing  Office,  Wash- 
ington, D.  C. 


Fig.  84  shows  a  typical 
Captain  John  Stephen  Sewell,  who  had 
charge  of  this  building  as  designing  and  constructing  engineer, 
thus  describes  the  general  methods  employed: 


*  A.  L.  A.  Himmel wright's  report  on  San  Francisco  fire,  page  150. 


370         FIRE    PREVENTION    AND    FIRE    PROTECTION 

The  columns  were  designed  to  carry  their  loads  alone, 
although  with  somewhat  higher  unit  strains  than  were  assumed 
for  girders  and  beams.  As  an  afterthought,  with  a  view  of 
eliminating  completely  the  danger  of  rust,  they  were  filled  with 
concrete.  They  were  composed  of  channels  placed  back  to 
back,  with  cover  plates  or  lattice  bars,  according  to  the  load. 
Where  not  built  into  the  walls  they  were  fireproofed  with  4 
inches  of  brickwork  and  all  the  space  between  this  covering  and 
the  columns  was  filled  either  with  concrete  or  with  mortar  and 
spalls,  which  amounts  to  the  same  thing. 

In  the  majority  of  cases  this  4-inch  brick  covering  served 
as  a  mold  for  the  concrete.  In  a  few  cases  where  it  was  desired 
to  fill  a  latticed  column  before  the  brickwork  was  built  around 
it,  a  rough  board  was  propped  up  against  the  side  containing 
the  lattice  bars.  As  soon  as  the  concrete  filling  had  set,  the 
board  was  removed.  The  space  between  the  brick  covering 
and  the  column  was  in  all  cases  filled  by  the  masons  with  mortar 
and  spalls,  as  they  were  laying  the  bricks. 

The  aggregate  used  was  broken  brick  or  broken  stone, 
broken  to  pass  a  1-inch  ring,  with  nothing  screened  out  but  the 
dust.  The  proportions  used  were  about  1,  4  and  9,  and  white- 
wash was  used  for  mixing  instead  of  water.  The  concrete  was 
put  in  as  occasion  offered,  after  the  columns  were  plumbed  and 
connected  and  before  other  work  had  advanced  to  points  where 
it  would  make  the  concreting  impossible.  The  concrete  had  to 
be  put  in  a  shovelful  at  a  time,  often  through  the  lattice  bars. 
As  it  usually  had  from  6  to  7  feet  to  40  feet  to  fall,  this  alone 
was  relied  upon  for  ramming.  It  was  made  as  wet  as  seemed 
safe,  to  secure  a  dense  mass;  but  this  had  to  be  watched  care- 
fully to  avoid  bursting  the  covering  on  latticed  columns  by 
hydrostatic  pressure.  In  one  case,  this  happened,  or  else  the 
moisture  in  the  filling  froze  and  the  result  was  the  same.  The 
covering  cracked,  but  was  not  removed  until  the  filling  was 
nearly  a  year  old.  It  was  then  found  to  be  exceedingly  hard 
and  dense,  and  was  apparently  accomplishing  the  object  for 
which  it  was  put  in,  so  far  as  such  a  short  test  could  indicate. 

The  cost  of  labor  involved  in  this  work  has  not  been 
finally  and  accurately  worked  out,  but  it  is  certainly  less  than 
$1.25  per  cubic  yard  of  concrete  placed,  which  seems  reasonable 
enough,  considering  the  conditions  under  which  it  had  to  be 
done.  The  main  difficulty  is  to  get  the  filling  done  at  the 
proper  time  without  delaying  other  work.  It  would  be  a 
troublesome  innovation  to  introduce,  on  this  account.  This 
difficulty  could  be  partially  avoided,  however,  if  it  were  con- 
sidered in  the  design  of  the  steelwork  from  the  beginning.* 

Where  brick  column  casings  are  used  in  United  States  Govern- 
ment buildings,  the  following  specification  is  ordinarily  used: 

Where  brick  casing  is  required  around  columns,  brick  must 

be  built  in  solid  around  the  steelwork  and  be  bonded  at  alternate 

*  See  Engineering  News,  October  23,  1902. 


COLUMNS   AND    COLUMN   PROTECTIONS  371 

courses.  A  space  must  be  left  between  the  brick  and  the  steel, 
which  must  be  filled  with  mortar  as  each  course  is  laid.  This 
space  must  be  about  \  inch  for  interior  columns  but  not  less 
than  1  inch  for  all  exterior  columns. 

Protection  of  Reinforced  Concrete  Columns.  —  It  haa 

previously  been  shown  in  Chapter  VII  that  even  reinforced 
concrete  requires  some  protective  covering  to  insure  the  integrity 
of  the  effective  load-bearing  area.  That  this  statement  is  par- 
ticularly true  of  reinforced  concrete  columns  is  demonstrated  by 
tests  made  in  1904  by  the  National  Fire  Proofing  Company  at 
their  Chicago  laboratory.* 

The  purposes  of  these  tests  were 

First,  to  determine  the  effect  of  a  continuous  fire  for  three 
hours,  at  an  average  temperature  of  1500  to  1600°  F.,  upon  the 
load-carrying  strength  of  a  concrete  column  10J  by  10i  inches 
square,  reinforced  with  four  steel  rods  f-inch  diameter. 

Second,  to  determine  the  effect  of  the  same  temperature, 
for  the  same  length  of  time,  upon  the  load-carrying  strength 
of  an  exactly  similar  column,  fireproofed  with  three  inches  of 
solid  porous  terra-cotta. 

The  results  showed  briefly: 

First,  that  an  unprotected  column  of  the  size  and  descrip- 
tion stated  above,  under  a  temperature  of  1500  to  1600°  F.  for 
three  hours,  will  lose  about  70  per  cent,  of  its  original  load- 
carrying  strength. 

Second,  that  a  similar  column,  protected  with  3  inches  of 
solid  porous  terra-cotta,  will  withstand  the  same  fire  test  with- 
out any  loss  in  original  strength. 

A  protective  .covering  for  reinforced  concrete  columns  may  be 
secured  in  three  different  ways:  1,  by  using  a  casing  of  terra- 
cotta; 2,  by  using  a  casing  of  cinder  concrete,  or  3,  by  increasing 
the  dimensions  of  the  column  in  the  original  design  by  a  sufficient 
amount  of  the  material  to  cover  possible  surface  damage  by  fire. 

1.  Terra-cotta  Protection.  —  Types  of  terra-cotta  protections 
suggested  by  the  National  Fire  Proofing  Company  are  shown 
in  Figs.  85  and  86.     Solid  porous  terra-cotta  blocks,  2}  inches 
thick,  are  held  to  the  concrete  by  metal  anchors  placed  as  shown, 
and  by  the  mechanical  bond  of  the  concrete  in  the  grooves  in  the 
tile. 

2.  Cinder  Concrete  Protection.  — The  following  very  practical 

*  For  description  of  these  tests  see  "Tests  of  the  Effect  of  Heat  on  Rein- 
forced Concrete  Columns,"  by  H.  B.  MacFarland,  Assoc.  Prof.,  Armour 
Institute,  Engineering  News,  September  20,  1906. 


372 


FIRE    PREVENTION    AND    FIRE    PROTECTION 


method  was  followed  in  building  the  reinforced  concrete  columns 
in  the  Bush  Terminal  Warehouses,  Brooklyn,  N.  Y. 

In  order  to  avoid  the  use  of  wood  column  forms  in  the  build- 
ings, the  cinder  concrete  casings  were  made  first.  These  con- 
sisted of  steel  wire,  wound  spirally,  covered  with  and  laced  to 
metal  lath,  each  section  being  two  feet  high.  These  metal  forms 
were  then  placed  within  cylindrical  wood  molds,  also  two  feet 
high,  and  of  a  radius  2  inches  larger  than  the  metal  form.  The 
2-inch  space  between  the  metal  form  and  wood  mold  was  then 


FIG.  85.  —  Terra-Cctta  Casing  for 
Reinforced  Concrete  Column. 


FIG.  86.  —  Terra-Cotta  Casing  for 
Reinforced  Concrete  Column. 


tamped  with  cinder  concrete,  which,  when  set,  allowed  the  wood 
mold  to  be  removed,-  thus  leaving  a  hollow  cylinder  of  cinder 
concrete  2  feet  high,  reinforced  on  the  inside  by  the  metal  mesh, 
etc.  It  will  be  noted  that  these  can  be  made  in  this  way  at  any 
convenient  place,  not  necessarily  at  or  near  the  building.  These 
cylinders  are  then  placed  one  over  the  other  until  the  required 
column  height  is  reached,  thus,  in  themselves,  making  forms 
within  which  the  column  reinforcement  rods  may  be  placed.  The 
interior  is  then  filled  with  the  load-bearing  concrete. 

3.  Increasing  Dimensions  of  Reinforced  Concrete.  —  The  cas- 
ings employed  in  methods  1  and  2,  just  described,  for  protecting 
reinforced  concrete  columns  against  fire  damage,  do  not  con- 
tribute to  the  strength  of  the  columns,  as  neither  terra-cotta 
veneer  nor  cinder  concrete  can  be  counted  on  for  any  positive 
load-bearing  value.  If,  however,  all  reinforced  concrete  col- 
umns were  to  be  originally  designed  and  built  of  such  dimensions 
that  the  outer  material,  to  a  depth  of  several  inches,  was  not  in- 
cluded in  the  load-bearing  area,  then  this  excess  material,  added 


COLUMNS   AND    COLUMN   PROTECTIONS  373 

at  the  perimeter,  could  suffer  complete  damage  by  fire  without 
affecting  the  safety  of  the  member.  Reconstruction  would  then 
involve  simply  a  resurfacing.  If  no  fire  damage  occurred,  the 
column  would  be  just  so  much  stronger  and  stiff er.  To  illus- 
trate: If  the  load  to  be  carried  required  a  10-inch  by  10-inch 
reinforced  concrete  column,  the  load-bearing  area  would  be  100 
square  inches.  If  this  were  protected  by  2  inches  of  cinder 
concrete,  the  column  would  occupy  practically  200  square  inches 
of  floor  space,  but  be  no  stronger  than  before.  If,  however,  the 
reinforced  concrete  column  were  made  14  inches  by  14  inches  in 
size,  thus  occupying  the  same  space  as  the  cinder  protected 
column,  the  load-bearing  area  would  then  be  200  square  inches, 
or  twice  the  effective  area  of  the  10-inch  column. 

The  only  uncertainty  in  this  method  is  the  probable  depth  of 
dehydration  under  fire.  The  efficacy  of  less  than  4  inches  of 
stone  concrete  under  any  severe  fire  test  would  be  problematical. 
Mr.  J.  D.  Galloway*  states  that,  in  the  San  Francisco  buildings, 
he  found  unprotected  concrete  dehydrated  and  ruined  to  a 
depth  of  4  inches;  also,  that  he  obtained  " samples  of  rock  con- 
crete which  were  dehydrated  to  a  depth  of  8  inches,  with  the 
written  statement  of  the  architect  that  the  concrete  was  originally 
first  class." 

Concrete-filled  Columns.  —  No  adequate  fire  tests  have 
ever  been  made  of  cast  or  steel  columns  filled  with  concrete,  but, 
while  there  is  little  question  that  such  tests  would  show  increased 
efficiency  over  unfilled  columns,  still,  the  practice  of  relying  on 
filling  instead  of  on  protective  envelopes  would  be  very  question- 
able, to  say  the  least.  In  the  San  Francisco  fire  a  few  light 
cast-iron  columns  filled  with  concrete  were  undamaged;  but  the 
principal  recommendations  attaching  to  this  practice  are  the 
added  stiffness  imparted  to  the  member  under  normal  or  fire 
conditions,  and  the  protection  of  the  column  interior  against 
corrosion,  as  was  pointed  out  in  Chapter  VIII.  For  a  further 
discussion  of  these  points  see  article  "  Columns  for  Buildings," 
by  John  Stephen  Sewell,  Captain  U.S.A.,  and  editorial,  in  Engi- 
neering News,  October  23,  1902. 

Pipe  Spaces.  —  It  has  been  pointed  out  in  Chapters  VIII 
and  IX  that  the  proper  installation  of  the  mechanical  plant  be- 
comes of  vital  importance  in  fire-resisting  construction.  All 
piping,  etc.,  should  be  carried  in  chases  or  compartments 

*  Transactions,  American  Society  of  Civil  Engineers,  Vol.  LIX,  page  329. 


374         FIRE    PREVENTION    AND    FIRE    PROTECTION 

especially  designed  as  pipe  receptacles,  these  to  be  preferably 
accessible  for  repairs  or  changes. 

As  a  matter  of  economy,  both  in  original  cost  and  in  the  matter 
of  space,  it  has  been  common  practice  to  run  water-,  waste-  and 
vent-pipes,  etc.,  immediately  alongside  the  steel  columns,  and 
inside  of  the  fire-resisting  covering.  Indeed,  open  forms  of  col- 
umns, such  as  the  Z-bar  and  Gray  types,  have  been  extensively 
recommended  as  giving  considerable  pipe  space  within  the 
minimum  circular  or  rectangular  casing. 

The  great  fire  damage  caused  by  this  detail  of  construction 
in  a  number  of  buildings  was  pointed  out  in  Chapter  VI,  while 
Figs.  55,  56,  58  and  59  in  the  present  chapter  show,  respec- 
tively, the  faulty  methods  followed  in  the  Parker  Building  and 
in  three  of  the  Baltimore  buildings.  In  all  of  these  instances 
the  presence  of  metal  conduits  or  piping  within  the  column  cover- 
ing caused  great  loss  to  the  casing,  and,  in  the  Parker  Building, 
to  the  columns  themselves.  The  expansion  under  heat  of  such 
piping  causes  inevitable  havoc  with  any  form  of  block  casing, 
and  it  is  probably  not  exaggeration  to  say  that  the  presence  of 
conduits  or  pipes  within  terra-cotta  column  casings  in  the  Balti- 
more and  San  Francisco  buildings  did  more  than  anything  else 
to  discredit  terra-cotta  column  protections.  The  same  damage 
would  be  wrought  to  metal-lath  and  plaster  casings,  and,  to  less 
extent,  to  concrete  or  brick  casings,  unless  of  adequate  thickness 
to  prevent  sufficient  conductivity  of  heat. 

The  best  practice  now  condemns  the  running  of  supply-,  vent-, 
waste-  or  other  pipes  within  the  same  enclosed  space  with  the 
steel  column.  Wherever  pipes  run  alongside  of  the  steel  columns, 
they  should  be  separated  from  the  columns  by  an  adequate  wall 
or  protection  of  fireproofing. 

In  the  newer  portion  of  the  Monadnock  Building,  Chicago, 
the  columns  were  fireproofed  as  shown  in  Fig.  87.  Hollow  bricks, 
laid  in  cement  mortar,  were  built  solidly  around  the  columns  to 
a  line  distant  4  inches  from  the  extreme  points  of  the  metal  wrork, 
and  a  2-inch  coating  of  hollow  tile  was  then  laid  against  the  brick 
backing,  and  extended  beyond  the  column  in  one  direction  to 
serve  as  a  space  for  the  reception  of  vertical  pipes. 

Practically  the  same  result  may  be  obtained  by  using  a  solid 
casing  of  porous  terra-cotta  or  concrete  around  the  column  in 
place  of  the  hollow  brick.  In  cases  where  independent  and 
accessible  pipe  chases  are  not  provided  this  detail  will  be  found 


COLUMNS   AND    COLUMN    PROTECTIONS 


375 


£§r  x-x 

'r\  N 

I  O  o 

rj 

DP 

I  o  o 

H 

IN 

o  s~\ 

v/////'  "•$ 

*9 

/ 

\^                                                       /  :>^ss>^F 

Hollow  Brick  ' 

as  satisfactory  as  any  that  can  be  used.  Fig.  88  shows  the 
method  followed  in  the  upper  stories  of  the  Chicago  Savings  Bank 
Building,  Holabird  and  Roche, 
architects. 

Fig.  89  illustrates  a  com- 
bined column  covering  and  pipe 
chase,  as  used  in  the  new 
Filene  Store  Building,  Boston, 
1912,  D.  H.  Burnham  &  Co., 


'  2  Hollow  Tile 


FIG.  87.  —  Brick  and  Terra-Cotta  Col- 
umn and  Pipe  Chase,  Monadnock 
Building,  Chicago. 


FIG.  88.  — Hollow  Tile  Pipe  Chase  at 

Column,  Chicago  Savings  Bank 

Building. 


architects.      The  isolated  columns  are  first  surrounded  with  a 
concrete  made  of  1  part  Portland  cement,  3  parts  torpedo  sand 


Plumbing 
-  Chase 


FIG.  89.  —  Concrete  and  Tile  Casing  and  Pipe  Chase,  Filene  Store  Building, 
Boston.  —  D,  H,  Burnham  &  Company,  Architects. 


376 


FIRE    PREVENTION    AND    FIRE    PROTECTION 


and  5  parts  stone  broken  to  pass  through  a  f-inch  mesh  screen. 
The  hollow  tile  coverings  are  made  of  special  shape,  each  block 
secured  to  adjoining  ones  by  means  of  keys,  and  to  the  columns 
by  means  of  heavy  galvanized  wire.  The  method  of  building 
these  casings  was  thus  specified: 

All  interior  columns,  where  fireproofed  with  tile,  shall,  as 
the  work  is  laid  up,  have  the  voids  between  the  steel  and  the 
tile  enclosure  completely  filled  with  stone  concrete.  This  work 
must  be  executed  as  the  laying  of  the  tile  progresses,  and  be 
solidly  tamped;  and  in  no  case  shall  the  tile  be  carried  more 
than  one  foot  above  the  filling  before  the  voids  are  again  filled. 

The  tile  arches  immediately  above  the  column  enclosures 
shall  be  left  out  until  the  column  enclosure  is  set  in  place,  to 
enable  the  thorough  fireproofing  of  the  columns. 

In  the  case  of  circular  or  elliptical  forms  the  casing  may  be 
made  eccentric  to  provide  the  necessary  room,   as  shown  in 


FIG.  90.  —  Hollow  Tile  Column  Casing 
and  Pipe  Chase,  Adams  Building, 
Chicago. 


FIG.  91.  —  Concrete  and  Metal  Lath 
and  Plaster  Column  Casing  and 
Pipe  Chase. 


Fig.  90  and  as  used  in  the  " Adams"  Building,  Chicago,  Hola- 
bird  and  Roche,  architects. 

A  concrete  and  metal  lath  and  plaster  casing,  including  space 
for  pipes  and  wires,  is  shown  in  Fig.  91. 


COLUMNS  AND  COLUMN  PROTECTIONS      377 

In  the  best  practice,  the  piping,  especially  if  of  any  consider- 
able size,  is  tied  to  and  partially  supported  by  the  floor  beams 
and  girders  by  means  of  anchors  or  straps. 

In  designing  the  pipe  space,  the  casing  should  preferably  be 
of  sufficient  thickness  to  prevent  the  transmission  of  enough  heat 
to  warp  the  piping;  or,  if  a  thin  casing  is  used,  the  piping  should 
be  kept  far  enough  away  from  the  casing  to  allow  of  a  reasonable 
amount  of  lateral  expansion  without  causing  contact  with  the 
envelope. 

The  methods  described  above  will  protect  the  columns  against 
attack  by  fire,  and  at  the  same  time  prevent  deterioration  from 
corrosion  due  to  the  immediate  presence  of  piping  near  the  metal 
members.  A  coating  of  some  waterproof  material  over  the 
inner  solid  casing  would  be  of  value  where  piping  is  run  in  this 
manner. 

Column  Guards.  —  In  mercantile  or  storage  buildings,  where 
hand  trucks  are  used  in  transferring  merchandise,  the  column 
shafts  should  be  protected  to  a  height  of  from  5  to  8  feet  by  iron 
or  wooden  column  guards. 

These  are  usually  made  of  i^-inch  or  f-inch  steel  plates,  spliced 
vertically.  They  may  be  fastened  either  to  the  finished  floor  or 
to  the  rough  underflooring.  The  guards  are  usually  made  with 
slightly  rounded  corners  for  rectangular  casings,  and  of  circular 
form  for  circular  columns,  and  of  size  to  fit  closely  around  the 
fireproofing.  The  plaster  finish  is  then  applied  to  the  fireproofing, 
coming  flush  with  the  metal  guards.  A  small  cast  moulding  is 
sometimes  attached  to  the  upper  edge  of  the  guard  to  conceal 
the  joint  between  the  guard  and  the  plaster. 

Three-quarter  inch  by  2-inch  oak  strips,  spaced  about  1 J  inches 
apart,  and  bound  by  iron  bands,  are  also  used  as  column  guards. 

Such  casings  form  a  valuable  protection  against  damage  from 
passing  trucks,  falling  packing  cases,  etc.,  all  of  which  tend,  in 
time,  to  loosen  or  even  break  the  fire-resisting  covering. 

Terra-cotta  Tile  Columns.  —  Remarkable  demonstrations 
of  the  load-carrying  capacity  of  columns  made  solely  of  blocks 
of  terra-cotta  tile  have  been  afforded  by  tests  made  by  the 
National  Fire  Proofing  Company,  and  by  trial  in  actual  practice. 
Special  forms  of  hollow  tile  blocks  have  developed  such  strength 
that  they  may  safely  be  used  as  columns,  without  metal  uprights 
of  any  kind,  in  buildings  of  seven  or  even  of  eight  stories  in 
height,  while  in  lower  structures,  tile  block  columns  of  several 


378 


FIRE    PREVENTION    AND    FIRE    PROTECTION 


forms  may  easily  be  designed  to  supplant  cast-iron  or  even  steel 
supports. 

"Monarch"  Tile  Block  Columns  are  made  of  special  hard- 
burned  blocks,  4  inches  by  8|  inches  in  area,  and  8  inches  long, 


I. 


FIG.  92.  — "Monarch"  Tile  Block 
Column,  Unit  Block. 


FIG.  93.  —  "  Monarch  "  Tile  Block 
Column,  17!  Inches  Square. 


with  1^-inch  outside  walls  and  1  J-inch  webs,  as  shown  in  Fig.  92. 
These  units  may  be  combined  to  form  rectangular  columns 
varying  in  size  from  8J  inches  square  up  to  31  inches  square, 
as  given  in  the  following  table.  The  arrangement  for  a  17£- 
inch  by  17^-inch  column  is  shown  in  Fig.  93. 

The  safe  loads  and   weights  per  lineal  foot  of  "Monarch" 
columns  are  given  in  the  following  table: 


Size  of  column. 

Safe  load  in 
pounds. 

No.  of  tile  in 
cross-section. 

No.  of  tile  per 
lineal  foot. 

Weight  of  col. 
per  lineal  foot. 

Ins. 

31  X31 

612,500 

24| 

36f 

Lbs. 
612 

31  X26£ 

525,000 

21 

31i 

525 

26JX26J 

450,000 

18 

27 

450 

26|X22 

375,000 

15 

22i 

375 

22  X22 

312,500 

121 

18| 

312| 

22  X17| 

250,000 

10 

15 

250 

17-1  Xl?i 

200,000 

8 

12 

200 

17^X13 

150,000 

6 

9 

150 

13  X13 

112,500 

41 

6! 

1121 

13  X  81 

75,000 

3 

41 

75 

8|X  81 

50,000 

2 

3 

50 

The  above  table  of  loads  is  based  on  columns  in  which  the  ratio  of  maximum 
height  to  least  dimension  is  twelve  to  one. 

Tests  have  developed  an  ultimate  strength  of  6,873  Ibs.  per 
square  inch  of  net  area  for  a  column  of  a  length  equal  to  eleven 
times  the  diameter.  The  joints  were  ^-inch  thick,  of  a  1:4 


COLUMNS  AND  COLUMN  PROTECTIONS 


379 


cement  mortar.  Another  test  column  of  18  diameters  developed 
a  strength  of  5,344  Ibs.  per  square  inch.  From  these  and  other 
tests,  the  National  Fire  Proofing  Company  claim  that  a  conser- 
vative safe  load  per  square  inch  of  net  area  in  compression  is 
1,000  pounds. 

This  type  of  column  was  used  throughout  the  Julin  Ware- 
house, Chicago,  1907. 

Reinforced  Terra-cotta  Columns.  —  An  experimental  test 
column  of  the  " Invincible"  pattern,  as  shown  in  Fig.  94,  was 


'wisted  SteeLRoda 


FIG.  94.  —  "  Invincible  "  Reinforced  Terra-Cotta  Column. 

tested  by  the  Robert  W.  Hunt  Company,  for  the  National  Fire 
Proofing  Company,  up  to  1,500,000  pounds,  or  4,109  pounds  per 


't  Floor I 

Footing 


FIG.  95.  —  "  Natco"  Column  Construction. 

square  inch  of  net  section,  without  sign  of  failure.     The  final 
compression  or  "set,"  after  the  load  was  removed,   was  but 


380         FIRE   PREVENTION   AND   FIRE   PROTECTION 

.006  inch  in  19  feet.  The  column  was  built  of  special,  hard- 
burned  tile,  laid  up  with  i-inch  Portland  cement  joints,  and 
reinforced  with  six  f-inch  twisted  steel  rods.  The  tile  were  laid 
in  two  concentric  rings,  the  inner  one  being  made  up  of  three 
tile,  and  the  outer  of  seven,  as  shown  in  Fig.  90.  The  reinforcing 
rings  were  placed  in  the  joints  between  the  inner  and  outer  rings. 

"Natco"  Column  Construction,  as  used  by  the  National  Fire 
Proofing  Company  for  residences  and  other  buildings  of  a  few 
stories  only,  is  shown  in  Fig.  95.  It  will  be  noted  that  the  ver- 
tical joints  between  the  tile  are  broken  in  the  alternate  courses. 
The  tile  should  be  slipped  over  the  vertical  reinforcing  rods,  and 
the  concrete  filling  should  be  poured  course  by  course. 

Conclusions.  — •  Column  protections  should  not  be  skimped 
or  slighted,  as  inadequate  thicknesses  of  materials  or  inefficient 
details  may  endanger  the  entire  structure.  Good  protection 
requires  a  more  or  less  increased  first  cost,  but  will  pay  for  itself 
in  added  security  to  the  structure,  and  in  reduced  reconstruction 
costs  after  fire. 

Average  present-day  methods  are  unsatisfactory,  but,  keeping 
the  commercial  aspect  in  mind,  methods  should  be  limited  or 
improved  as  follows: 

Single  metal  lath  and  plaster,  not  trustworthy,  should  not  be 
used. 

Double  metal  lath  and  plaster  with  air-space,  efficient  for  ordi- 
nary hazards,  light  in  weight,  easy  of  reconstruction. 

Gypsum  blocks  combine  light  weight,  low  conductivity  and 
little  or  no  expansion  under  heat,  but  are  subject  to  calcination 
and  erosion;  severe  test  usually  requires  complete  replacement. 

Terra-cotta  tile,  excellent  material  if  porous,  but  often  com- 
bine insufficient  thickness  with  poor  workmanship.  Casings 
should  be  made  of  smaller  sized  and  heavier  tile,  3  inches  or 
4  inches  in  thickness,  well  wired  or  anchored,  casings  to  be  pref- 
erably circular  to  avoid  corners,  laid  in  cement  mortar.  Added 
expense  over  usual  inefficient  casings  would  be  small,  but  would 
result  in  greatly  increased  efficiency  and  low  reconstruction  costs. 

Cinder  concrete,  light,  efficient  and  cheap;  usually  requires 
forms  for  building;  subject  to  erosion,  but  reconstruction  easy. 
Corrosive-  tendencies  questionable. 

Brick,  nothing  more  efficient,  but  heavy  and  expensive. 


CHAPTER  XIII. 

FIRE-RESISTING  PARTITIONS 

Functions  of  Partitions.  —  The  word  partition  is  here  used 
principally  to  designate  those  light  and  easily  removable  walls 
or  screens  which  are  not  depended  on,  in  the  least,  for  the 
structural  entity  of  the  building,  but  which  are,  nevertheless,  of 
great  importance  in  the  fire-resisting  qualities  which  should  be 
developed  in  the  plan. 

Although  the  following  discussion  of  partitions  will  be  equally 
applicable  to  all  classes  of  buildings  intended  to  be  fire-resisting, 
some  of  the  points  to  be  especially  emphasized  will  be  made 
plainer  if  applied  to  those  buildings  which  are  commonly  divided 
into  comparatively  small  units  of  area  by  means  of  numerous 
partitions  —  as,  for  example,  hotels,  apartment  houses,  or  office 
buildings. 

It  will  be  seen  at  once  that  such  dividing  walls  have  two  en- 
tirely distinct  functions  to  fulfill.  The  first  is  that  of  light 
screens  to  subserve  purely  architectural  requirements  as  to  the 
subdivision  of  large  areas  into  those  units  of  space  required  by 
the  use  of  the  building  —  in  other  words,  to  form  offices,  rooms 
or  corridors,  or  to  enclose  stairs,  elevators,  or  other  architectural 
subdivisions. 

The  second  function  of  such  partitions  is  their  ability  to  act 
as  fire-stops,  either  simply  to  localize  incipient  fire,  or,  more 
broadly,  to  contribute  to  the  safety  and  efficiency  of  the  structure 
as  a  ivhole,  when  threatened  by  severe  conditions  from  either 
within  or  without. 

Now  it  is  perfectly  evident  that  these  two  separate  functions, 
architectural  and  fire-resisting,  are  almost  impossible  of  ideal 
realization  in  one  and  the  same  partition  —  at  least  under  present 
ordinary  methods  of  design;  for,  to  serve  the  architect's  require- 
ments of  subdivision,  doors  must  be  introduced  for  intercom- 
munication, and  frequently  window  openings  or  toplights  are 
used  for  the  transmission  of  light  from  room  to  corridor  or  from 
corridor  to  room,  the  openings  usually  occurring  on  at  least  one, 

381 


382         FIRE    PREVENTION    AND   FIRE    PROTECTION 

and  frequently  more  sides  of  every  unit  of  area.  But,  from  the 
standpoint  of  fire-resistance,  such  openings  should  be  dispensed 
with  entirely,  as  their  presence  diminishes  the  efficacy  of  the 
partition  in  direct  proportion  to  their  number  and  size.  In- 
deed, some  fire  protectionists  go  so  far  as  to  say  that  any  plan 
requiring  windows  or  toplights  in  partitions  for  the  purpose  of 
lighting  corridors  or  other  areas  is  proved  defective  through  this 
error  or  weakness  in  design  alone.  This  is  undoubtedly  a  rather 
unfair  claim,  considering  the  limitations  and  economy  of  room 
usually  forced  upon  the  architect,  but,  nevertheless,  it  is  still 
unfortunately  too  true  that  at  least  ninety-five  partition  con- 
structions out  of  one  hundred  show  that  the  architectural 
functions  of  partitions  are  utilized,  while  their  fire-resisting 
functions  are  hardly  considered.  This  is  evidenced  by  the 
heretofore  almost  universal  introduction  of  wood  doors  and 
frames  and  wood  toplight  sash  and  trim  into  so-called  fire- 
resisting  partitions.  If  the  partitions  are  really  intended  to 
contribute  any  fire-resistance  whatever  to  the  structure,  there 
can  be  no  excuse  for  using  wood  doors  or  window  areas,  while, 
conversely,  if  wood  doors  and  trim  are  to  be  used,  why  go 
to  the  useless  expense  of  providing  fire-resisting  partitions 
when  lighter  and  cheaper  plaster  constructions  will  be  found 
quite  as  effective  against  fire  as  the  woodwork  introduced,  and 
even  quite  as  effective  as  the  ordinary  terra-cotta  partition  used 
in  conjunction  with  woodwork?  To  quote  from  the  motto  used 
by  a  well-known  fireproof  door  company,  "A  fireproof  door  is 
not  intended  for  a  wood  partition,  neither  is  a  wood  door  in- 
tended for  a  fireproof  partition."  Consistent  partition  construc- 
tion would  involve  either  the  use  of  materials  throughout  which 
are  confessedly  non-fire-resisting  —  wood  studs,  plaster,  wood 
doors  and  sash  — •  or  else  materials  and  constructions  of  no  sham 
or  false  pretense,  which  will  really  prove  fire-resisting  in  deed  as 
well  as  in  hopes. 

Requirements  of  Fire-resisting  Partitions.  —  An  ade- 
quate fire-resisting  partition  must  fulfill  the  following  require- 
ments : 

1.  Architectural  service,  to  secure  convenient  subdivisions  of 
area. 

2.  Fire-resisting  arrangement  or  planning. 

3.  Fire-resisting  qualities,  or  ability  to  resist  attacks  by  fire 
and  water. 


FIRE-RESISTING    PARTITIONS  383 

4.  Stability  of  position,  or  ability  to  resist  hose  streams  or 
falling  de'bris;   and,  of  particular  importance  in  some  cases, 

5.  Deadening   qualities,    in   preventing   the   transmission   of 
sound. 

The  architectural  functions  of  partitions  and  their  planning  or 
fire-resisting  arrangement  should  be  worked  out  together.  The 
proposed  use  of  the  building  and  its  exposure  will  determine  the 
particular  points  of  fire-safety  which  need  most  consideration  — 
whether  the  isolation  of  especially  dangerous  risks,  the  safety  of 
large  numbers  of  people  through  flame  and  smoke  cut-off's,  or 
the  localizing  of  many  areas  within  which  risks  are  equal,  as  has 
been  previously  discussed  at  greater  length  in  Chapter  IX, 
paragraph  " Subdivision  of  Large  Areas." 

It  will  bear  repeating  that  the  second  requirement,  viz.,  the 
fire-resisting  planning  of  partitions,  should  mean  more  in  any 
important  building  than  the  mere  ability  of  partitions  simply 
to  localize  incipient  fire.  The  structure  should  be  considered 
as  a  whole,  in  connection  with  its  exposure,  its  neighbors,  and 
its  own  inherent  dangers,  in  an  endeavor  to  provide  against 
wide-spread  fire  loss  from  either  interior  or  exterior  severe  con- 
ditions. In  other  words,  what  element  of  safety  to  the  structure 
may  the  whole  partition  system  contribute,  in  subdividing  the 
building  into  protected  main  areas  by  means  of  solid  brick  divid- 
ing walls?  These  areas  to  be  again  divided  by  less  efficient 
partitions,  but  still  amply  fire-resisting,  all  to  be  so  distributed 
and  constructed  as  to  make  even  conflagration  conditions  less 
destructive  than  would  otherwise  be  the  case.  This  possible 
office  of  partition  planning  is  generally  lost  sight  of,  and  yet  it 
is  safe  to  say  that  had  this  general  principle  been  considered  in 
any  of  the  so-called  fire-resisting  buildings  destroyed  in  the  Bal- 
timore and  San  Francisco  fires,  large  interior  areas,  away  from 
the  direct  lines  of  attack,  might  have  been  found  almost  un- 
touched in  many  structures. 

The  interior  construction  of  the  building  should  be  such 
that,  should  a  fire  by  any  chance  be  introduced  from  the  out- 
side, it  could  be  confined  absolutely  to  the  room  or  rooms  to 
which  it  finds  access.  Such  a  thing  as  a  conflagration  sweeping 
through  a  building  can  be  made  impossible  at  reasonable  ex- 
pense, provided  unnecessary  architectural  finish  be  omitted  and 
the  money  ordinarily  expended  on  it  be  applied  to  other  things.* 

*  Captain  John  Stephen  Sewell,  in  United  States  Geological  Bulletin  No. 
324,  page  128." 


384         FIRE    PREVENTION    AND    FIRE    PROTECTION 

Requirements  3  and  4,  or  the  ability  of  partitions  to  resist 
fire  while  still  retaining  their  integrity  of  position  under  hose 
streams  or  shock  from  falling  debris,  will  be  considered  in  later 
paragraphs,  as  will  also  the  deadening  of  sound  qualities  of 
various  constructions. 

Types  of  Partitions  in  Common  Use.  —  Partitions  may 
be  divided  into  two  general  classes,  viz.,  load-bearing,  or  those 
partitions  which  carry  floor  or  other  structural  loads,  and  non- 
load-bearing,  or  those  partitions  which  are  introduced  for  divi- 
sional purposes  only. 

The  former  include  brick,  concrete,  tile,  and  combination  tile 
and  concrete.  The  latter  include  light  sheathings,  etc.  (gen- 
erally non-combustible  rather  than  thoroughly  fire-resisting),  and 
the  more  efficient  metal  lath  and  plaster,  plaster-block,  terra- 
cotta, and  concrete  constructions.  These  will  now  be  examined 
in  some  detail,  both  as  regards  their  fire-resisting  qualities  and 
their  construction,  etc. 

For  partitions  enclosing  vertical  openings,  see  Chapters  XV 
and  XVI. 

Tests  of  Partitions  in  Various  Fires.  —  As  to  actual  fires, 
exceptions  may  be  quoted  which  will  apparently  overthrow  any 
general  deductions,  and  still  it  is  undoubtedly  true  that  common 
experience  has  shown  the  utter  unreliability  of  average  present- 
day  methods.  Indeed,  present  types  of  so-called  fire-resisting 
partition  construction  constitute  the  weakest  feature  in  fire- 
resisting  design.  This  is  due  not  so  much  to  the  materials 
employed  in  the  best  constructions  as  to  the  methods  of  their 
use.  Wood  doors,  windows,  wooden  base  strips  and  frames,  in- 
stability under  hose  streams  or  falling  material,  and  carelessness 
in  erection  have  all  been  contributing  factors  in  this  recognized 
inefficiency. 

Numerous  examples  have  been  quoted  in  Chapter  VI,  —  the 
Home  Office  Building  where  tile  partitions  were  built  upon 
wood  strips,  the  Granite  Building  in  Rochester  where  wooden 
strips  were  built  into  the  tops  of  the  partitions  at  the  ceiling 
line  (see  Fig.  96),  and  the  Home  Life  and  Parker  Buildings, 
where  wooden  doors,  windows  and  trim,  etc.,  made  a  disastrous 
result  inevitable.  In  the  Home  Life  Building,  thin  plaster  par- 
titions were  also  shown  to  be  inefficient. 

Partitions  in  Baltimore  Fire.  —  Without  quoting  testimony 
from  the  individual  buildings,  it  may  be  said  that  the  Baltimore 


FIRE-RESISTING    PARTITIONS  385 

fire  demonstrated  the  utter  inefficiency  of  all  partition  construc- 
tions there  tested,  viz.,  thin  metal  lath  and  plaster,  terra-cotta 


FIG.  96.  — Granite  Building  Fire.    View  on  8th  Floor. 

or  tile,  and  plaster  block.  The  results  were  unexpected,  even 
to  those  most  familiar  with  fire-resisting  methods.  The  writer, 
in  a  three  days'  critical  examination  of  the  buildings,  did  not 
find  a  single  example  of  a  stable  and  undamaged  partition  which 


386         FIRE   PREVENTION    AND    FIRE   PROTECTION 

had  been  subjected  to  a  severe  test.  The  following  summary 
from  the  report  of  the  National  Fire  Protection  Association  states 
the  conditions  plainly  but  fairly: 

All  room  partitions,  as  ordinarily  constructed  of  hollow 
tile,  plaster  blocks,  metal  lath  and  plaster  or  similar  materials, 
are  readily  destroyed  by  severe  fire. 

The  above  statement  is  intended  to  call  attention  to  the 
fact  that  such  partitions  are  by  no  means  fireproof,  although  in 
some  degree  fire-resistive,  and  that  the  damage  to  them  will 
necessitate  considerable  expenditure  for  their  reconstruction. 
The  fact  should  not  be  overlooked,  however,  that  any  subdi- 
vision by  incombustible  partitions  is  of  value  in  retarding  the 
spread  of  fire. 

Hollow  terra-cotta  tile  5  inches  or  more  in  thickness  is 
the  most  desirable  partition  of  the  types  enumerated  above, 
but,  like  tile  coverings  for  columns,  the  ordinary  method  of 
construction  is  not  sufficiently  rigid.  This  is  due  partly  to  the 
use  of  large  blocks  set  up  on  end,  to  the  use  of  a  poor  quality  of 
mortar,  and  to  the  fact  that  the  tile  breaks  when  subjected  to 
severe  heat. 

The  destruction  of  the  tile  partitions  in  the  Baltimore 
buildings  would  also  appear  to  be  largely  due  to  the  absence  of 
substantial  non-combustible  supports. 

The  total  failure  of  the  plaster-block  partitions  was  con- 
spicuous, as  they  softened  and  crumbled  away  completely 
under  heat.  Partitions  made  of  plaster  on  metal  lath  seem  to 
make  a  better  showing  where  no  water  is  used,  but  in  all  cases 
the  supporting  studs  were  of  light  metal,  and  these  collapsed 
before  the  plaster  was  fairly  tested.  Plaster  partitions  have 
made  a  poor  showing  in  former  fires  where  water  was  used.* 

Partitions  in  San  Francisco  Fire.  —  A  most  drastic  criti- 
cism of  partition  constructions  is  contained  in  the  report  on  the 
San  Francisco  fire  made  by  the  committee  of  members  of  the 
American  Society  of  Civil  Engineers,  as  follows: 

Partitions  were  of  terra-cotta  tile,  and  of  wire  lath  and 
plaster,  either  solid  or  hollow.  All  kinds  were  destroyed.  In 
the  tile  partitions  the  mortar  joints  were  disintegrated,  the 
plaster  was  destroyed,  and  the  tiles  were  made  brittle.  One 
could  pull  down  with  the  hand  any  partition  in  the  Mills  Build- 
ing, all  of  which  were  of  tile.  Metal  lath  and  plaster  partitions 
were  completely  wrecked,  but  the  lath  might  be  considered  as 
salvage.  The  use  of  wooden  grounds  around  doors  and  tran- 
soms helped  the  destruction,  but  it  is  difficult  to  see  what  would 
have  prevented  the  damage.* 

•  Transactions  Am.  Soc.  C.  E.,  Vol.  LIX,  page  239. 


FIRE-RESISTING    PARTITIONS  387 

Captain  Sewell  is  just  about  as  pessimistic:  "In  a  general  way 
it  may  be  said  that  practically  all  the  interior  partitions  that 
were  not  built  of  brickwork  were  a  total  loss,  being  absolutely 
inadequate."* 

However,  it  should  be  stated  that  much  misrepresentation  has 
occurred,  especially  through  photographs,  of  partition  and  other 
damage  in  the  San  Francisco  buildings.  This  has  been  due  to 
not  differentiating  between  earthquake  damage  and  fire  damage. 
Thus  the  conditions  in  the  Hall  of  Justice  have  often  been  shown 
pictorially  as  pointing  to  the  failure  of  partitions,  column  pro- 
tections, suspended  ceilings,  etc.;  whereas  this  building  was  con- 
fessedly badly  racked  by  the  earthquake.  Lath  and  plaster 
partitions  in  the  Fairmont  Hotel  have  also  been  quoted,  whereas 
the  real  cause  of  failure  lay  in  the  great  settlement  of  many  floors, 
several  feet  in  cases,  due  to  the  settling  of  columns  in  lower  stories. 

Partition  Tests.  —  More  or  less  systematic  fire  and  water 
tests  on  partition  constructions  have  been  made  by  the  New 
York  Building  Department,  by  the  Underwriters'  Laboratories, 
and  by  the  British  Fire  Prevention  Committee.  Special  terra- 
cotta load-bearing  partitions  have  been  tested  for  strength  only 
by  the  National  Fire  Proofing  Company,  as  described  in  a  later 
paragraph . 

It  must  be  borne  in  mind,  however,  as  was  previously  pointed 
out  in  Chapter  VI,  that  experimental  tests  are  not  comparable 
in  practical  value  to  tests  afforded  by  actual  fires.  This  is  par- 
ticularly true  of  partitions,  for  the  reason  that  test  conditions 
usually  comprise  small  areas,  unpierced  by  doors  or  windows, 
while  actual  tests  reveal,  of  necessity,  the  weaknesses  inherent 
to  practical  usage.  This  point  is  further  discussed  in  a  later 
paragraph  "  Reasons  for  Failure  of  Tile  Partitions." 

The  New  York  Bureau  of  Buildings  requires  that  all  proposed 
fire-resisting  partition  constructions  shall  satisfactorily  pass  a 
uniform  test  before  being  approved  for  use.  The  conditions  of 
this  test  have  previously  been  given  in  Chapter  V,  page  124. 
The  test  houses  used  are  also  similar  to  those  described  in  Chap- 
ter V,  the  partition  materials  or  constructions  forming  the  long 
sides  of  the  kiln. 

These  tests  were  inaugurated  in  1901,  at  which  time  22  differ- 
ent partitions,  representing  14  distinct  types  of  manufacture 
(6  of  plaster  blocks,  1  of  concrete  blocks,  5  of  metal  lath  and 
*  Bulletin  No.  324,  page  72. 


388         FIRE    PREVENTION    AND    FIRE   PROTECTION 

plaster  and  2  of  terra-cotta  tile)  were  subjected  to  trial.  Some 
of  these  will  be  referred  to  in  detail  under  later  headings,  but  they 
may  be  briefly  summarized  as  follows:* 

The  plaster-block  or  composition  partitions  all  showed  portions 
washed  away  by  the  action  of  hose  streams,  the  cellular  blocks 
being  so  destroyed  as  to  expose  the  interior  cells. 

The  metal  lath  and  plaster  partitions  showed  no  serious  damage 
to  the  metal  frameworks,  but  the  plaster,  i.e.,  the  only  fire- 
resisting  medium,  was  more  or  less  destroyed  on  the  fire  side 
where  water  was  applied,  although  the  partitions  were  still 
capable  of  reconstruction  in  every  case. 

Of  concrete-block  partitions,  one  test  only  was  made.  In  this, 
the  plaster  was  stripped  from  the  .exposed  wall,  but  the  partition 
proper  remained  plumb  and  apparently  uninjured. 

Terra-cotta  partitions  were  subjected  to  two  tests.  The  only 
effect  of  the  fire  was  to  destroy  the  plaster  in  places. 

Various  other  constructions,  including  reinforced  concrete, 
have  been  tested  during  the  years  following  1901. 

The  Underwriters1  Laboratories,  Inc.,  have  favorably  passed  a 
number  of  materials  and  devices  for  partition  construction  under 
certain  limitations.  Thus  hollow  "Pyrobar"  partition  blocks, 
made  of  gypsum,  and  Sackett  plaster  board  and  gypsinite  stud- 
ding, are  approved  under  certain  conditions,  as  will  be  shown 
later. 

The  British  Fire  Prevention  Committee  have  devoted  seventeen 
of  their  "Red  Books"  to  tests  of  various  partition  constructions, 
nearly  all  of  which  are  of  essentially  English  practice.  Two  of 
the  tests,  however,  are  of  decided  interest. 

"Red  Book"  No.  102  describes  a  fire  and  water  test  on  a 
9-inch  wall  and  a  3-inch  partition  made  of  "asbestic"  bricks,  viz., 
sand-lime  bricks  made  with  an  admixture  of  asbestic.  Both 
wall  and  partition  failed  completely  by  collapse. 

The  test  of  a  porous  terra-cotta  partition  described  in  "Red 
Book"  No.  99  is  referred  to  in  detail  on  page  402. 

United  States  Geological  Survey  Tests,  made  at  the  Under- 
writers' Laboratories,  Inc.,  Chicago,  included  two  tests  of  par- 
tition tile.  These  tests  are  described  on  page  402. 

Load-bearing  Partitions  may  be  of  brick,  concrete,  or  of 
structural  tile,  but  as  such  partitions  are  generally  classed  as 
walls,  they  will  be  discussed  in  Chapter  XX.  Combination  tile 

*  For  detailed  account,  see  Engineering  News,  December  26,  1901. 


FIRE-RESISTING    PARTITIONS 


389 


and  concrete  walls,  suitable  for  moderate  loads,  are  described  in 
Chapter  XXIV. 

The  desirability  of  providing  efficient  "fire"  or  -'cut-off" 
walls,  either  surrounding  dangerous  portions  of  the  structure, 
or  surrounding  hazardous  contents,  or  in  limiting  areas,  as  pre- 
viously discussed  in  Chapter  IX,  would  point  to  the  advisability 
of  considering  the  possibilities  of  all  load-bearing  partitions  from 
these  standpoints. 

Non-load-bearing  Partitions.  —  Interior  partitions  of  or- 
dinary thicknesses,  whether  of  plaster,  composition  or  terra- 
cotta, are  usually  assumed  as  forming-  a  portion  of  the  dead 
load  carried  by  the  floor  system.  They  are  placed  in  almost  any 
position  on  the  floor,  regardless  of  the  locations  of  the  floor 
beams. 

Hollow  Metal  Lath  and  Plaster  Partitions.*— ^  A  hollow 
partition,  finishing  4  inches  thick,  is  constructed  by  the  Roebling 
Construction  Company  as  shown  in  Fig.  97.  The  studs  are  made 


FIG.  97.  —  Hollow  Metal  Lath  and  Plaster  Partition. 

of  2-inch  by  i-inch  flats,  spaced  12  inches  centers,  fastened  top 
and  bottom  by  means  of  knees.  Angles  or  channels  are  used  to 
frame  for  all  openings. 

Stiffened  wire  lathing  is  secured  to  both  sides  of  the  studs  to 
receive  the  plaster,  which  consists  of  three  coats  on  each  side  — • 
scratch,  brown  and  finishing  coats.  Wood  furring  blocks, 
where  required,  are  attached  to  the  studs,  or  to  the  wire  rods 
woven  into  the  netting,  by  means  of  staples. 

The  weight  per  square  foot  is  22  pounds,  including  plaster. 

A  type  of  hollow  plaster  partition  erected  by  the  Expanded 
Metal  Companies  is  made  of  2-inch,  3-inch  or  even  4-inch 
" Prong  Lock"  patent  studs,  made  by  the  Berger  Manufacturing 
Company  as  shown  in  Fig.  98.  These  are  spaced  about  12  inch 


*  For  description  of  Metal  Laths,  etc.,  see  "Furring,"  Chapter  XXI. 


390 


FIRE    PREVENTION    AND    FIRE    PROTECTION 


centers,  fastened  top  and  bottom  to  channels  laid  along  the 
partition  lines,  and  stiffened  by  means  of  horizontal  members  or 
bridging  cut  in  between  the  studs. 
Metal  lath  is  then  locked  to  both 
sides  of  the  uprights,  which,  when 
plastered,  leaves  an  air-space  over  the 
entire  area. 

Another  hollow  partition  constructed 
by  the  same  companies  is  made  of  studs 
which  consist  of  two  J-inch  angle  irons, 
riveted  together  with  pieces  of  light 
strap  iron  every  2  feet  or  3  feet  in 
height  (see  Fig.  99).  For  ordinary 
partitions,  the  angles  are  generally 
placed  4  inches  out  to  out,  which,  with 
the  lathing  and  plaster  on  both  sides, 
makes  the  total  thickness  6  inches. 
The  studs  are  set  12  inches  centers. 

The  studs  are  held  top  and  bottom 
by  means  of  straps  or  angle  knees, 
which  are  bolted  to  the  studs  and 
nailed  directly  to  the  floor  arches.  A 
1-2-inch  slotted  hole  is  left  in  the  top 
knees,  to  allow  for  inequalities  in  height. 
Expanded  metal  lath,  No.  24  gauge,  is 
usually  employed,  with  gauged  Portland 
cement  mortar. 

This  detail  may  be  used  for  any 
thickness  of  partition,  to  enclose  vent  flues,  heating  pipes  or 
other  features  which  may  require  a  thick  double  partition. 


FIG.    98.  — "Prong    Lock' 
Partition  Studs. 


FIQ.  99.  —  Hollow  Plaster  Partition,  Expanded  Metal  Company's  Type. 

Solid  Metal  Lath  and  Plaster  Partitions.  —  A  2-inch  solid 
plaster  partition  used  by  the  Roebling  Construction  Company 


FIRE-RESISTING    PARTITIONS  391 

is  shown  in  Fig.  100.     The  studs  consist  of  either  f-inch  channels 
or  1-inch  by  A -inch  flats,  spaced  16  inches  centers,  secured  by 


FIG.  100.  —  2-inch  Solid  Plaster  Partition. 

top  and  bottom  knees  to  the  floor-arch  construction.  Where 
stone  concrete  floors  are  used,  wood  plugs  are  inserted  for  fasten- 
ings, while  for  cinder  concrete  slabs  or  fill,  nails  are  driven. 

No.  24  gauge  expanded  metal,  or  wire  lathing  stiffened  with 
\ -inch  solid  steel  wires  or  ribs  woven  in  every  7J  inches,  is  laced 
to  one  side  of  the  studs  with  No.  18  galvanized  wire.  If  stiffened 
wire  lathing  is  used  the  sheets  are  so  placed  as  to  make  the 
stiffening  ribs  run  at  right  angles  to  the  studs. 

All  openings  for  doors,  transoms,  windows,  etc.,  are  framed 
with  1-inch  by  1-inch  by  TO-inch  angles  or  by  means  of  f-inch 
channels.  The  vertical  members  at  door  openings  are  made  to 
extend  the  full  height  from  floor  to  ceiling.  Such  members 
around  openings  are  punched  at  intervals  with  holes  to  permit 
the  fastening  of  the  wood  frames,  etc. 

Wood  furrings,  f-inch  thick,  are  placed  between  the  studs  to 
receive  the  base  boards,  chair  rail  and  picture  moulding.  These 
furrings  are  usually  placed  by  the  carpenter,  and  are  held  by 
staples  going  around  the  studs  or  around  the  j-inch  rods. 

The  partition  is  then  plastered  with  some  hard  plaster  or  with 
gauged  mortar.  This  is  applied  in  five  coats,  giving  a  total 
thickness  to  the  partition  of  2  inches.  The  weight  including 
plaster  is  20  pounds  per  square  foot. 

Another  form  of  solid  partition  used  by  the  same  company 
is  made  of  a  combination  of  cinder  concrete  and  plaster  on  an 
iron  framework,  as  shown  in  Fig.  101.  The  studs  are  made  of 
2-inch  by  |-inch  flats,  spaced  18  inches  centers,  extending  from 
concrete  floor  plate  to  ceiling.  They  are  fastened  by  bending 
the  ends  of  the  flats  to  form  small  knees,  which  are  spiked  to 
the  floor  construction.  Openings  are  framed  by  means  of  2-irich 
by  2-inch  by  J— inch  angles,  or  by  channels  of  the  same  size  as 
the  studs,  punched  to  allow  the  securing  of  wood  frames. 


392          FIRE    PREVENTION    AND    FIRE    PROTECTION 

Upright  angles  at  sides  of  doorways  extend  the  full  height  of 
the  partition. 

After  all  of  the  iron  framework  is  in  position,  with  the  necessary 
door  frames,  either  No.  24  gauge  expanded  metal  or  stiffened 
wire  lathing  is  laced  to  both  sides  of  the  studs.  If  the  latter  is 
used,  the  |-inch  stiffening  ribs,  spaced  every  7|  inches  centers, 


Fia.  101.  — 4-inch  Solid  Plaster  Partition. 

are  run  at  right  angles  to  the  studs.  The  space  between  the 
two  surfaces  of  wire  lathing  is  then  filled  solid  with  a  cinder  con- 
crete composed  of  1  part  Portland  cement  and  8  parts  cinders. 
This  completely  embeds  the  studs  within  a  concrete  slab  about 
2J  inches  thick.  Two  coats  of  plaster,  a  brown  coat  and  a  finish- 
ing coat,  are  then  applied  to  the  outer  surface  of  the  lathing, 
making  a  partition  of  a  total  thickness  of  4  inches.  No  wood 
furring  is  necessary  for  attaching  the  base  board,  chair  rail 
or  picture  moulding,  as  the  cinder  concrete  will  receive  nails. 
The  weight  per  square  foot,  including  plaster,  is  32  pounds. 

For  both  of  these  forms  the  light  channels  or  angles  are  cut 
and  fitted  at  the  building  as  required.  Temporary  bracing  dur- 
ing plastering  is  not  necessary,  although  it  is  sometimes  resorted 
to,  and  even  required  by  architects. 

A  2-inch  solid  plaster  partition  is  also  made  by  the  Expanded 
Metal  Companies  consisting  of  f-inch  or  1-inch  upright  channel 
studs,  to  one  side  of  which  expanded  metal  lath  is  wired.  The 
studs  are  placed  12  inches  centers,  the  ends  being  bent  to  form 
small  knees,  which  are  secured  to  the  floor  and  ceiling  by  means 
of  nails,  screws,  toggle  bolts  or  other  fastenings,  depending  upon 
the  conditions  encountered.  The  sheets  of  metal  lath  are  wired 
at  least  four  times  to  each  stud,  and  also  at  the  laps,  No.  18  soft 
wire  being  used  for  this  purpose. 

For  a  temporary  bracing  during  plastering,  f-inch  horizontal 
channels  are  wired  to  the  studs  on  the  side  opposite  the  lathing, 
one  brace  being  used  in  low  partitions,  and  two  rows  in  partitions 


FIRE-RESISTING    PARTITIONS  393 

over  12  feet  in  height.  The  plaster  is  first  applied  to  the  lath 
side.  After  this  coat  has  set,  or  in  about  a  day's  time,  the  back 
side  of  the  partition  is  plastered  out  to  the  face  of  the  studs. 
The  bracing  is  then  removed  by  cutting  the  wires  and  the  surface 
is  patched  where  the  horizontal  channels  occurred.  Patent  or 
hard  plasters  are  generally  used,  as  common  mortar  requires  too 
long  a  time  for  thorough  drying,  and  is  not  sufficiently  rigid. 

This  partition  weighs  about  15  pounds  per  square  foot. 

For  these  various  forms  of  solid  plaster  partitions  a  cement 
base  board  is  sometimes  moulded  in  position  by  the  plasterer 
while  applying  the  finish  coat.  A  cement  floor-strip  may  also 
be  made,  extending  12  inches  or  18  inches  out  from  the  partition. 

Fire  Tests  of  Metal  Lath  and  Plaster  Partitions.  —  The 
tests  of  the  New  York  Building  Department,  1901,  included  a 
2^-inch  solid  metal  lath  and  plaster  partition  constructed  by 
the  New  York  Expanded  Metal  Company.  The  construction 
consisted  of  a  framework  of  1-inch  by  iVinch  uprights,  placed 
12  inches  centers,  and  expanded  metal  lathing.  King's  Windsor 
cement  mortar  and  an  inside  finish  coat  of  white  putty  plaster 
were  used  to  make  up  the  total  thickness.  The  effects  of  the 
fire  and  water  test  were  as  follows: 

The  browning  coat  on  the  outside  of  the  east  partition  had 
fallen  for  about  two-thirds  the  area  of  the  partition.  The  out- 
side scratch,  coat  was  intact.  The  inside  browning  coat  had 
been  washed  away  by  the  water.  On  the  west  partition  a  2  by 
2  foot  square  of  the  outside  browning  coat  and  about  four- 
fifths  of  the  inside  browning  coat  and  one-half  of  the  inside 
scratch  coat  had  been  washed  away.  In  no  place  had  the  fire 
or  water  passed  through  either  partition. 

Both  solid  and  hollow  partitions  of  the  Roebling  type  were 
also  tested.  The  latter,  which  gave  the  better  results,  was  3 
inches  thick,  made  of  2  by  J-inch  uprights  with  stiffened  wire 
mesh,  and  J  inch  of  "Rock  Wall"  plaster  on  each  side.  The 
effects  of  the  test  included  "the  washing  away  of  about  three- 
fifths  of  the  plaster  from  the  inside  wall.  The  piaster  on  the 
outside  wall  was  intact,  and  in  no  place  had  the  fire  or  water 
penetrated  the  partition." 

Plaster-block  Partitions.  —  Plaster  blocks,  made  principally 
of  gypsum  or  plaster  of  Paris,  with  an  admixture  of  wood  fiber, 
reeds  or  other  suitable  material,  are  used  in  partition  construc- 
tion. They  possess  many  commendable  qualities,  but  some 
great  disadvantages. 


394 


FIRE   PREVENTION   AND   FIRE   PROTECTION 


They  are  extremely  light  in  weight,  easy  to  handle  and  rapid 
of  erection,  besides  being  superior  in  the  non-conductivity  of 
both  heat  and  sound.  They  can  also  be  readily  cut  and  sawed, 
while  grounds  or  trim  may  be  toe-nailed  directly  to  the  blocks. 
They  are,  too,  slightly  cheaper  than  other  forms  of  block  partitions. 

Plaster  blocks,  besides  their  poor  resistance  to  hose  streams 
which  is  considered  in  a  later  paragraph,  possess  several  dis- 
advantages in  actual  use.  First,  the  very  fact  that  the  material 
will  receive  nails  for  the  attachment  of  trim  often  means  the 
pulling  away  of  such  trim  when  placed  by  careless  workmen, 
owing  to  the  fact  that  nails  are  frequently  driven  into  the  voids 
in  the  blocks,  thus  giving  no  hold.  Second,  practical  builders 
find  that  the  highly  absorbent  qualities  of  the  blocks  lead  to  the 
absorption  of  the  water  in  the  plastering,  and  this  moisture  works 
down  the  partition  in  a  cumulative  measure,  and  often  collects  in 
sufficient  quantity  at  the  floor  line  to  warp  and  ruin  wood  base,  etc. 

Plaster  blocks  are  usually  made  with  cylindrical  core  holes 
which  should  be  placed  horizontally  in  the  setting.  The  vertical 
joints  should  be  broken.  Mortar  should  consist  of  1  part  gypsum 
plaster  mortar  to  3  parts  sand,  joints  to  be  not  over  one-half 
inch.  In  topping  out  or  setting  the  top  course  of  blocks,  story 
heights  are  usually  such  as  to  require  a  special  height  filler 
course  at  the  top,  in  which  case  the  blocks  may  be  cut  to  fit,  but 
placed  with  the  core  holes  vertical.  The  top  joint  should  be 
well  filled  with  mortar,  but  not  wedged.  Either  metal  " bucks" 
or  frames  should  be  used  at  openings,  or  else  the  blocks  should 
be  arched  over  the  heads. 

"Pyrobar"  Blocks,  made  by  the  United  States  Gypsum 
Company,  are  made  of  95  per  cent,  gypsum  and  5  per  cent,  wood 
fiber  in  the  form  of  excelsior.  The  ordinary  sizes  of  the  blocks 
with  their  weights  per  square  foot  and  limiting  heights  for  sub- 
stantial partitions  are  as  follows: 


Size. 

Weights  per 
square  foot, 
in  Ibs. 

Height  of 
partition  not 
to  exceed 
in  feet. 

2X12X30  ins. 

hollow  (furring)  

5i 

2X12X30  ins. 

solid 

8 

10 

3X12X30  ins. 

hollow.  .        .         .... 

9 

13 

4X12X30  ins. 

hollow  

11 

17 

6X12X24  ins. 

hollow 

17 

28 

8X12X15  ins. 

hollow   . 

23 

40 

12X12X12  ins. 

hollow  

35 

40 

FIRE-RESISTING   PARTITIONS  395 

About  8  pounds  per  square  foot  should  be  added  to  the  above 
weights  for  plaster  on  two  sides  of  partition.  Where  the  unsup- 
ported length  of  partition  exceeds  30  feet,  the  thickness  should 
be  increased  one  inch  for  any  of  the  permissible  heights  given 
above  for  blocks  under  6  inches  thick. 

When  set  on  incombustible  foundation,  laid  with  broken 
joints  in  properly  retarded  gypsum  plaster,  and  coated  on  each 
side  with  wood  fibered  gypsum  plaster  at  least  \  inch  in  thick- 
ness, hollow  '  Pyrobar '  Partition  Blocks  are  approved  for  use  in 
non-bearing  corridor  and  room  partitions  not  exceeding  13,  17 
and  22  feet  in  height  for  the  3-,  4-  and  5-inch  blocks  respectively, 
in  fireproof  office  buildings  and  buildings  of  this  class,  but  not 
for  bearing  walls  or  partitions,  nor  for  enclosures  to  stairways 
and  elevators  or  important  vertical  openings  through  buildings.* 

-*" Pyrobar"  blocks  will  cost  about  8J  to  9  cents  per  square 
foot  for  3-inch  hollow  partitions,  set,  ready  for  plaster;  and  about 
10  cents  per  square  foot  for  4-inch  partitions. 

"Keystone"  Plaster  Blocks,  as  made  by  the  Keystone  Fire- 
proofing  Company  of  Philadelphia  and  New  York,  are  composed 
of  calcined  gypsum  and  a  small  proportion  of  wood  fiber.  The 
standard  sizes  of  partition  blocks  and  weights  of  same  per  square 
foot,  unplastered,  are  as  follows: 

2X15X24    ins.,  solid  9  pounds 

3X15X24    ins.,  cored  9       " 

4X15X24    ins.,       "  10i     " 

5X12X18    ins.,       "  13      " 

6X15X191  ins.,       "  14      " 

8X12X18    ins.,       "  18      " 

Permissible  partition  heights  may  be  taken  the  same  as  pre- 
viously given  for  " Pyrobar"  blocks. 

Plaster  of  Paris  and  Cinder  Blocks.  —  Various  mixtures  of 
plaster  of  Paris  and  cinders  have  been 'used  in  the  manufacture 
of  so-called  fireproof  blocks  for  floor  arches,  partitions,  etc. 
Thus  lime-of-Tiel  blocks,  described  in  Chapter  VII,  page  257, 
were  composed  of  plaster  of  Paris,  cinders,  and  a  small  proportion 
of  Tiel  lime.  Later  mixtures  have  included  plaster  of  Paris  and 
cinders  only,  usually  in  the  proportion  of  2  parts  to  3  parts. 
Such  blocks  are  termed  "ash"  or  "cinder"  blocks,  but  no  in- 
creased fire-resisting  efficiency  has  resulted  from  this  admixture 
of  materials.  The  most  that  can  be  said  of  such  blocks  is  that, 
*  Underwriter's  Laboratories,  Inc. 


396 


FIRE   PREVENTION   AND   FIRE   PROTECTION 


while  they  are  no  better  from  a  fire-resisting  standpoint,  they 
are  usually  cheaper  than  those  made  of  pure  gypsum. 

The  New  York  Building  Department  tests  included  two 
cinder-block  constructions  —  the  "Bell,"  and  the  metal-braced 
"Sanitary"  type  —  but  neither  have  had  any  extended  use. 

Interlocked  Plaster-block  Partitions.  —  An  interesting 
attempt  to  secure  increased  lateral  stability  in  plaster  or  cinder- 
block  partition  construction  is  illustrated  in  the  "interlocking" 
fireproof  partition  block  patented  by  the  Conroy  Brothers.  These 
were  made  12  inches  high,  24  inches  long  and  3  inches  thick,  of 


End        %"! 


Side  Elevation 


'  Section 


Horizontal  Section 
FIG.  102.  —  Conroy  Interlocking  Plaster  Blocks. 

plaster  of  Paris  and  cinders.  The  use  of  tongued  arid  grooved 
edges  and  cement  mortar  joints  was  intended  to  provide  added 
rigidity  in  the  construction.  The  blocks  had  a  series  of  central 
air-spaces,  and  two  outer  sets  of  combined  air-spaces  and  per- 
forations which  acted  as  lath  or  key  for  the  plaster  finish,  as 
shown  in  Fig.  102.  The  test  of  this  construction  is  described 
in  the  following  paragraph. 

Fire  Tests  of  Plaster-block  Partitions.  —  Several  tests  of 
plaster-block  partitions  have  been  made  by  the  British  Fire 
Prevention  Committee  (see  "Red  Books"  Nos.  37,  52,  74  and 
86),  but  these  were  of  compositions  or  constructions  peculiar 
to  English  practice. 

The  tests  made  by  the  New  York  Bureau  of  Buildings  in  1901 
(before  referred  to),  supplemented  by  additional  tests  in  later 
years,  constitute  by  far  the  most  exhaustive  experimental  fire 
and  water  tests  which  have  been  made  of  plaster- block,  or  indeed 


FIRE-RESISTING    PARTITIONS  397 

of  any  other  ordinary  type  of  partition  construction.  Of  six 
plaster-block  constructions  tested  in  1901,  four  were  composed  of 
wood  fiber,  and  two  of  cinders,  mixed  with  plaster  of  Paris. 
Three  types  contained  metal  reinforcement  of  some  kind,  three 
did  not.  Several  of  the  constructions  were  tested  for  both  hol- 
low and  solid  blocks.  The  results  show  that,  in  general,  there 
is  little  choice  between  the  several  compositions  or  constructions. 
In  no  case  did  either  fire  or  water  pass  through  the  partition, 
but  in  nearly  all  instances  the  blocks  were  calcined  to  an  average 
depth  of  perhaps  three-fourths  of  an  inch,  and  the  material, 
with  the  plastering,  was  washed  away  by  the  hose  streams.  If 
anything,  the  hollow  block  partitions  suffered  the  most. 

An  exceptionally  good  showing  was  made  by  the  patented 
partition  constructed  by  Conroy  Brothers.  These  tongued  and 
grooved  plaster  and  cinder  blocks  have  been  described  under 
the  previous  heading.  The  report  of  the  test,*  which  was  made 
in  cooperation  with  the  New  York  Bureau  of  Buildings,  contained 
the  following: 

The  application  of  water  knocked  off  the  inside  plaster  on 
the  north  wall  from  three  small  patches,  about  3  square  feet  in 
all,  and  a  similar  patch  about  2  feet  wide  by  8  feet  long  was 
washed  off  from  the  south  wall.  Numerous  cracks  existed  in 
the  balance  of  the  plaster,  and  a  portion  of  it  was  loose.  The 
blocks  exposed  by  falling  off  of  plaster  were  apparently  unin- 
jured. With  the  exception  of  the  defects  already  noted,  both 
partitions  were  in  excellent  condition.  They  were  firm,  solid 
and  apparently  capable  of  withstanding  another  test. 

A  test  of  " Keystone"  gypsum-block  partitions  was  made  by 
Professor  Woolson,  in  conjunction  with  the  New  York  Bureau 
of  Buildings,  in  1906.  Two  standard-test  partitions  —  one  of 
2-inch  solid  blocks,  the  other  of  3-inch  cellular  blocks  —  were 
subjected  to  the  usual  test  conditions.  The  results  were  as 
follows : 

After  forty  minutes'  firing,  an  L-shaped  crack  appeared  in 
the  plaster  on  the  2-inch  partition,  near  the  middle  and  about 
2  feet  6  inches  above  the  grate.  Each  leg  of  the  crack  was 
about  2  feet  long.  Later,  about  a  foot  of  plaster  peeled  off 
between  these  cracks,  but  so  far  as  could  be  observed,  this  was 
the  only  defect  which  appeared  up  to  the  time  the  water  was 
applied.  The  application  of  water  knocked  off  all  the  plaster 
from  both  partitions  and  washed  away  practically  all  the  in- 

*  See   Columbia    University   Fire  Test   Series  No.    154,   by  Prof.   Ira  H. 
>lson,  October,  1904. 


Wool 


398 


FIRE    PREVENTION   AND    FIRE    PROTECTION 


side  web  of  the  3-inch  hollow  block  partition.  On  the  2-inch 
solid  block  partition,  most  of  the  surface  of  the  blocks  was 
washed  away  to  a  depth  varying  from  J  inch  to  1  inch.  The 
blocks  all  remained  in  place,  however,  and  the  partitions  were 
plumb  and  firm.  Viewed  from  the  outside,  the  walls  appeared 
as  perfect  as  they  were  before  the  test.  Not  a  crack  was  visiile 
in  the  outside  plaster  on  either  partition,  and  neither  fire, 
smoke  nor  water  came  through  them  at  any  point. 

Terra-cotta  Tile  Partitions:  Sizes  of  Blocks.  —  The  blocks 
employed  are  either  square  or  brick  shaped,  according  to  local 
practice  or  the  ideas  of  the  manufacturer.  Square  blocks  are 


6x8x12  6x12x12  4x12x12         4x8x12      3xl2.x_12    2  x  8.x  12 

FIG.  103.  — Semi-Porous  Terra-Cot ta  Partition  Blocks. 


4x8x12         4x12x12         6x8x12  6x12x12       2x12x122x8x12 

FIG.  104.  —  Porous  Terra-Cotta  Partition  Blocks. 

commonly  made  12  ins.  by  12  ins.  for  the  body  of  the  par- 
tition, with  6-in.  by  12-in.  and  8-in.  by  12-in.  blocks  for  filling 
in  the  end  spaces,  or  the  tops  of  the  partitions.  For  brick- 
shaped  blocks,  a  variety  of  sizes  are  used  by  different  manu- 
facturers, 6-in.  by  12-in.,  and  8-in.  by  12-in.  constituting  the 
more  ordinary  face  dimensions.  Typical  partition  blocks  are 
shown  in  Figs.  103  and  104. 

Thickness  of  Blocks.  —  Partition  blocks  are  made  in  thick- 
nesses varying  from  2  inches  to  12  inches,  the  3-inch,  4-inch  and 
6-inch  blocks  being  the  most  common.  A  4-inch  partition  is  the 
most  popular  thickness  for  ordinary  work.  With  plaster  on  both 
sides,  this  will  finish  about  5J  inches  total  thickness.  For  office 
buildings,  common  practice  has  been  to  use  4-inch  partitions 


FIRE-RESISTIN.G    PARTITIONS 


399 


for  the  main  corridors  and  stairway  and  elevator  enclosures,  etc., 
and  3-inch  partitions  between  rooms.  Two-inch  tile  parti- 
tions should  never  be  used  unless  braced  (see  later  heading 
"Metal-braced  Block  Partitions"),  and  even  then,  only  in  short 
lengths  and  heights,  and  in  unimportant  locations.  Even  3-inch 
tile  partitions  are  not  to  be  recommended  for  dependable  effi- 
ciency. Experience  gained  in  the  Baltimore  and  San  Francisco 
fires  points  to  the  necessity  for  more  mass  and  greater  stability 
in  terra-cotta  partitions  of  ordinary  lengths  and  heights,  and 
4-inch  blocks  should  be  the  minimum  thickness  in  buildings 
subject  to  either  severe  exposure  or  considerable  interior  hazard. 
For  severe  conditions,  6-inch  blocks  are  preferable. 

Stock  Sizes.  —  The  following  sizes  of  partition  blocks  are 
usually  carried  in  stock  by  the  National  Fire  Proofing  Company : 


2  inches  thick. 

3  inches  thick. 

4  inches  thick. 

5  inches  thick. 

6  inches 

thick. 

Ins. 

Ins. 

Ins. 

Ins. 

Ins. 

6X12 

6X12 

6X12 

8X12 

8X12 

8X12 

8X12 

8X12 

12X12 

12X12 

12X12 

12X12 

12X12 

These  sizes  may  be  had  in  either  "semi-porous"  or  "porous" 
tile. 

Weights.  —  The  weights  per  square  foot  of  tile  partitions, 
without  plaster,  will  average  about  as  follows: 

2-in.         3-in.         4-in.       5-in.         6-in. 

Semi-porous  tile,     12  Ibs.     15  Ibs.     16  Ibs.     18  Ibs.     24  Ibs. 

Porous  tile,  14  Ibs.     17  Ibs.     18  Ibs.     20  Ibs.     26  Ibs. 

If  plastered  on  both  sides,  add  10  pounds  per  square  foot  to 
the  above. 

Height  and  Length.  —  The  safe  height  of  a  terra-cotta  par- 
tition may  be  approximated  by  multiplying  the  thickness  in 
inches  by  40.  This  will  give  the  safe  height  in  inches.  Com- 
mon practice  allows: 

3-inch  partitions,  a  safe  height  of  12  feet. 
4-inch  partitions,  a  safe  height  of  16  feet. 
6-inch  partitions,  a  safe  height  of  20  feet. 

The  previously  stated  rule  will  give  less  heights  than  this  for 
the  3-inch  and  4-inch  partitions,  and  is  to  be  preferred  for  best 
workmanship. 


400         FIRE    PREVENTION    AND    FIRE    PROTECTION 

For  partitions  without  any  side  supports,  the  length  should 
not  materially  exceed  the  safe  height.  Doors  and  high  windows 
may  be  considered  as  side  supports,  provided  the  studs  run  from 
floor  to  ceiling. 

Method  of  Setting  Tile  Partitions.  *-  It  should  be  an  in- 
variable rule  to  place  all  partitions  directly  upon  floor  beams  or 
girders,  or  upon  the  fire-resisting  floor  arch.  They  should  not 
be  placed  upon  wood  screeds  nor  upon  cinder  concrete  filling. 
Careful  adherence  to  this  practice  will  prevent  many  failures 
which  might  otherwise  occur  under  fire  test. 

At  least  a  portion  of  the  partition  should  be  built  of  full  porous 
blocks,  in  order  to  provide  for  the  nailing  on  of  wood  trim.  In 
ordinary  work,  where  semi-porous  tile  are  generally  used,  about 
15  per  cent,  of  the  tile  should  be  made  full  porous  for  this  pur- 
pose. The  lowest  course  of  tile  should  be  made  either  entirely 
of  porous  blocks,  or  of  porous  alternating  with  the  semi- porous 
blocks,  and  additional  courses  or  portions  of  courses  of  the 
porous  make  should  also  be  introduced  for  the  receipt  of  chair 
rail  or  picture  moulding.  Full  porous  blocks  are  slightly  more 
expensive  than  semi-porous,  as  they  weigh  more  per  square  foot, 
and  have  heavier  faces  and  webs;  but  they  make  a  better  par- 
tition, and  are  decidedly  more  dependable  under  fire  test. 

Tile  partition  blocks  should  always  be  set  on  end,  bond- 
broken  at  all  vertical  joints.  At  the  ceiling,  " closures"  of  the 
required  size  are  inserted,  often  on  their  sides,  but  driven  as 
tightly  as  possible,  and  then  made  secure  by  wedging  with  slate. 
This  wedging  is  very  essential  to  make  the  partition  rigid  and 
secure  against  side  pressure.  Some  manufacturers  claim  that 
it  is  best  to  start  setting  the  partitions  in  the  lower  stories  first, 
as  the  partition  weights  added  to  the  successive  stories  above 
will  then  cause  additional  deflections  to  the  beams,  and  bring 
added  pressure  to  the  tops  of  the  partitions  below.  Others  insist 
that  the  partitions  should  be  started  at  the  top  first,  thus  avoid- 
ing the  increments  due  to  the  deflections  story  by  story.  If  the 
partitions  are  well  wedged  with  slate  at  each  story,  as  should  be 
done  in  all  cases,  the  best  results  will  probably  obtain  by  working 
down  from  the  upper  floors.  Otherwise,  sufficient  deflection  may 
be  obtained  in  the  lower  stories  to  partially  crush  or  buckle  the 
partitions. 

If  wood  studs  are  used  for  door  or  window  openings,  they 
should  run  the  full  length  from  floor  to  ceiling.  They  should 


FIRE-RESISTING   PARTITIONS  401 

be  as  thick  as  the  partition  blocks  and  well  straightened,  so  that 
grounds  may  be  applied  to  receive  the  plastering,  or  they  may 
be  made  1£  inches  wider  than  the  blocks,  so  as  to  act  as  grounds 
also.  Where  wood  studs  extend  through  the  partition,  as,  for 
instance,  below  high  window  areas,  they  should  be  fastened  to 
the  adjacent  tile  blocks,  and  then  lathed  across  the  face  with 
metal  lath  of  some  manufacture  which  will  form  a  key  for  the 
mortar  or  plaster  between  the  lath  and  stud.  This  will  allow 
the  stud  to  shrink  without  cracking  the  plaster. 

Wooden  frames  should  never  be  relied  upon  to  sustain  the 
partition  blocks  over  doors  or  other  openings.  If  the  use  of 
wood  frames  is  insisted  upon,  however,  the  partition  material 
should  be  made  to  form  a  flat  arch  over  the  openings. 

Partitions  containing  wood  studs  or  frames,  or  even  wood  trim 
to  any  appreciable  amount,  cannot  be  classed  as  fire-resisting. 
Metal  " bucks"  or  frames,  or  incombustible  trim,  are  essential 
for  maximum  efficiency,  as  is  pointed  out  in  later  paragraphs. 

One  of  the  simplest  and  best  ways  to  secure  terra-cotta  par- 
titions where  they  abut  against  brick  walls  is  to  drive  large 
cut-nails  into  the  mortar  joints  of  the  masonry  at  the  top  of 
each  course  of  blocks,  before  setting  the  next  course.  The 
heads  of  the  nails  will  then  come  between  the  terra-cotta  blocks, 
and  by  tapping  them  down  with  a  hammer  at  the  successive 
courses,  great  additional  stiffness  may  be  obtained. 

Most  makes  of  partition  tile  are  now  grooved  or  " scored"  to 
provide  a  key  for  the  plastering.  All  blocks,  whether  porous 
or  hard-burned,  should  be  well  wet  before  setting,  and  again  wet 
before  the  plastering  is  applied.  Otherwise  the  absorption  will 
sap  the  mortar  before  the  cement  receives  its  proper  set.  The 
most  satisfactory  mortar  for  setting  partitions  is  made  of  1  part 
lime  putty,  2  parts  cement  and  2  to  3  parts  sand. 

Fire  Tests  of  Tile  Partitions.  —  In  addition  to  the  general 
information  given  in  previous  paragraphs  concerning  the  records 
of  partition  constructions  in  various  fires  and  conflagrations,  and 
concerning  tests  which  have  been  made,  the  following  somewhat 
detailed  descriptions  of  fire  and  water  tests  on  tile  partitions  will 
be  found  instructive  in  considering  failure  vs.  efficiency. 

The  partition  built  by  Henry  Maurer  &  Son,  and  tested  by  the 
New  York  Bureau  of  Buildings,  September  30,  1901,  consisted  of 
8  by  12  by  3-inch  semi-porous  blocks  with  two  cells  in  each  block. 
The  partition  was  14  feet  6  inches  long  and  9  feet  6  inches  high. 


402         FIRE   PREVENTION   AND   FIRE    PROTECTION 

The  blocks  were  laid  to  break  vertical  joints,  the  mortar  being 
one  part  cement  to  three  parts  sand.  Each  side  was  plastered 
£  inch  thick.  After  the  usual  test  of  one  hour,  reaching  a  maxi- 
mum temperature  of  1832°  F.,  a  hose  stream  was  applied  for 
2i  minutes.  "The  only  effect  of  the  fire  and  water  had  been 
to  remove  the  plaster  from  a  portion  of  the  inside  of  the  parti- 
tion. Wherever  the  plaster  remained  the  bond  was  intact." 

"Red  Book"  No.  99  of  the  British  Fire  Prevention  Committee 
describes  a  similar  test  made  August  16,  1905,  on  a  partition  of 
2J-inch  porous  tile  blocks,  submitted  by  the  National  Fire 
Proofing  Company.  The  plastering  was  destroyed,  the  face  of 
one  tile  on  the  fire  side  split  off,  and  a  2J-inch  bulge  occurred 
towards  the  fire.  "Neither  fire,  smoke  nor  water,  passed 
through  the  partition  itself,  which  remained  in  position  at  the 
conclusion  of  the  test."  The  introductory  note  gives  the  follow- 
ing summary: 

This  test  indicates  that  it  is  possible  to  provide  parti- 
tions 2J  inches  thick  (2|-inch  slabs  and  f-inch  plastering), 
having  a  length  of  10  feet  and  a  height  of  8  feet  10  inches,  that 
will  prevent  the  passage  of  flame  and  smoke  from  a  fire  burning 
for  two  and  a  half  hours  on  the  plastered  side  of  the  partition, 
raising  the  temperature  to  1980°  F.,  and  then  prevent  the 
passage  of  water  from  a  steam  fire  engine  jet. 

It  is  interesting  to  compare  these  two  tests  with  the  following. 
The  United  States  Geological  Survey  Tests,*  made  at  the  Under- 
writers' Laboratories,  Inc.,  Chicago,  included  two  panels  of  par- 
tition tile,  the  blocks  being  12  by  12  by  5  inches,  f-inch  thick 
material,  and  with  three  core  holes  each.  They  were  obtained 
from  a  Chicago  building  in  course  of  construction.  The  test 
panels  were  6  feet  wide  by  9  feet  high,  and  were  subjected  to  a 
temperature  of  about  1750°  F.  for  two  hours,  after  which  they 
were  quenched  with  water.  In  both  cases,  the  backs  of  the  tiles 
(away  from  the  fire)  were  apparently  as  sound  as  before  the 
test.  In  one  case  these  backs  were  slightly  cracked,  in  the  other 
not  at  all.  The  exposed  faces  fared  much  worse.  In  one  panel 
55  per  cent.,  in  the  other  75  per  cent.,  of  the  faces  were  either 
broken  off  or  could  readily  be  removed,  while  all  of  the  faces 
could  easily  be  crumbled  by  hand. 

It  seems  difficult  to  reconcile  these  results  with  the  British 
Fire  Prevention  Committee  test  before  given,  especially  as  both 

'  *  See  United  States  Geological  Survey  Bulletin  No.  370. 


FIRE-RESISTING    PARTITIONS  403 

the  area  tested,  the  temperature,  and  the  duration  were  greater 
in  the  English  test.  The  explanation  is  undoubtedly  to  be  found 
in  the  qualities  and  thicknesses  of  the  materials.  The  official 
description  of  the  Chicago  tests  does  not  state  definitely  as  to  the 
quality  of  tile  used,  —  whether  porous,  semi-porous,  or  hard- 
burned  —  simply  that  it  was  purchased  in  Chicago  from  a 
building  being  erected.  From  the  results  of  the  tests,  so  similar 
to  previous  experiences  with  hard  tile,  there  would  appear  to 
be  little  question  that  the  blocks  were  of  that  material,  or  at 
least  of  very  poor  quality  of  semi-porous.  Again,  in  the 
English  test  the  blocks  were  12  by  12  by  2|  inches  in  size,  with 
3  cores  each  3  inches  by  \  inch  passing  vertically  through  each 
block.  Thus  the  faces  were  It  inch  thick,  with  a  web  only 
\  inch  long  every  4  inches.  In  the  Chicago  tests  the  faces  were 
|  inch  thick,  held  by  f-inch  webs,  3|  inches  long,  every  4  inches. 

Reasons  for  Failures  of  Tile  Partitions.  —  A  comparison 
between  the  actions  of  tile  partitions  in  actual  fires  and  under 
experimental  tests  will  show  that  the  causes  of  failures  under 
the  former  conditions  have  been  due  to  the  manner  in  which 
the  material  was  used,  rather  than  to  the  fire-resisting  qualities 
of  the  material  itself.  Test  conditions  and  actual  conditions  are 
very  different. 

Test  conditions  usually  involve  partitions  of  less  length,  if 
not  of  less  height,  than  are  required  in  actual  practice,  and,  in 
addition,  such  partitions  are  always  constructed  by  the  manu- 
facturer with  the  utmost  care,  and  without  openings  of  any  kind. 

Actual  conditions  involve  practical  questions  concerning 
lengths,  heights,  wood  floors,  wood  studs,  doors,  windows,  trim, 
etc.,  besides  the  indifference  of  ignorant  or  careless  workmen. 
To  secure  thoroughly  trustworthy  partitions  under  severe  fire 
test,  these  practical  weaknesses  must  be  overcome. 

As  to  lengths  and  heights,  too  little  consideration  has  been 
given  to  the  stability  of  tile  block  partitions.  Thinner  blocks 
than  called  for  in  the  preceding  rules  for  heights  or  lengths 
should  not  be  used  unless  some  approved  form  of  braced  parti- 
tion is  employed,  or  unless  steel  door  bucks  or  approved  fire- 
resisting  frames  are  introduced  at  openings.  As  a  result  of  the 
general  inefficiency  of  tile  partitions  in  both  the  Baltimore  and 
San  Francisco  buildings,  many  fire  protectionists  are  advocating 
decidedly  thicker,  and  hence  more  stable,  partitions  than  have 
been  customary  in  the  past. 


404         FIRE   PREVENTION   AND   FIRE    PROTECTION 

The  main  practical  difficulties  met  with  in  constructing  tile 
partitions  are  caused  more  by  the  carpenter's  work  than  by  the 
fireproofer's  work.  Thus  for  the  support  of  the  partitions  upon 
the  floor  construction,  it  has  been  said  that  partitions  should 
always  run  down  to  the  masonry  construction,  and  not  rest  upon 
the  wooden  flooring.  But  the  carpenter  will  soon  raise  decided 
objections,  and  use  all  arguments  to  avoid  this.  For  if  planks 
fastened  directly  to  the  top  flanges  of  the  beams  are  to  be  used 
as  an  underflooring,  the  carpenter  much  prefers  to  lay  a  con- 
tinuous floor,  and  have  the  partitions  built  upon  this  planking. 
His  reasons  are: 

First,  that  it  is  much  cheaper  for  him,  as  this  requires  less 
labor  in  cutting  and  fitting,  though  somewhat  more  stock. 

Second,  as  many  of  the  partitions,  if  run  down  to  the 
masonry,  would  be  placed  directly  upon  the  beams  or  girders,  the 
carpenter  would  have  no  fastening  for  the  planking  coming 
against  such  partitions,  but  the  next  beam,  possibly  4,  5  or  6  feet 
away,  would  have  to  be  used,  thus  leaving  the  planks  loose  at 
the  ends. 

If  an  underflooring  of  J-inch  rough  boarding  is  used,  fastened 
to  screeds  buried  in  the  concrete  filling,  the  running  down  of 
the  partitions  to  the  concrete  requires  the  carpenter  to  place 
screeds  at  each  side  of  the  partitions,  and  this  is  objected  to  on 
account  of  the  expense. 

If  hard-burned  terra-cotta  only  is  used  in  the  partitions,  a 
wooden  ground  is  needed  for  the  attachment  of  the  base  or 
wainscot.  The  carpenter  usually  prefers  to  lay  a  solid  nailing 
strip  the  full  width  of  the  partition,  and  have  the  partition  built 
upon  this. 

The  inconsistency  of  introducing  wood  studding  or  frames, 
doors,  windows,  etc.,  into  fire-resisting  partitions,  has  previously 
been  discussed,  and  yet  this  self-evident  weakness  from  a  fire- 
protection  standpoint  has  been  responsible  for  more  failures  and 
greater  damage  to  tile  partitions  than  all  other  causes  combined. 
Quantities  of  partitions  are  still  being  erected  in  this  manner,  in 
spite  of  the  lessons  taught  in  the  Baltimore  and  San  Francisco 
fires;  and  in  the  Continental  Trust  Company's  Building,  Balti- 
more, where  more  partition  damage  was  due  to  this  cause  than 
to  all  other  causes  combined,  the  same  construction  has  again 
been  repeated  in  the  restoration  of  the  structure.  The  corridor 
partitions  have  again  been  made  of  3-inch  or  4-inch  tile  blocks, 


FIRE-RESISTING    PARTITIONS  405 

up  to  a  height  of  7  feet,  above  which  the  same  old  practice  of 
wood  and  glass  sash  has  been  repeated. 

Such  errors  should  be  avoided  through  the  use  of  some  ap- 
proved type  of  fire-resisting  doors  and  door  frames  (examples 
of  which  will  be  mentioned  later),  and  through  the  use  of  either 
cast-iron,  metal-covered,  or  composition  window  frames  and 
sash  in  combination  with  wire  glass. 

Many  other  failures  of  tile  partitions  have  resulted  from  con- 
structive defects,  such  as  partitions  left  free  at  the  top  without 
proper  wedging,  lack  of  support  at  ends,  or  from  attempting  to 
provide  end  support  by  combining  the  partition  construction 
with  the  column  protection,  as  shown  on  the  left-hand  side  of 
Fig.  107. 

Metal-braced  Block  Partitions.  —  A  number  of  partition 
constructions  have  been  invented  and  used  to  a  limited  extent, 
consisting  of  either  plaster  or  terra-cotta  blocks  in  combination 
with  some  form  of  metal  bracing,  the  effort  being  to  secure  either 

1.  Additional  lateral  strength  for  ordinary  partition  thick- 
nesses, in  order  to  provide  against  the  abnormal  conditions  in- 
cident to  the  pressure  of  hose  streams  or  the  shock  of  falling 
debris  during  fire,  or 

2.  The  use  of  thinner  partitions  than  could  otherwise  be  used, 
thus  economizing  in  material,  weight,  and  floor  space. 

Several  plaster-block  partitions  of  this  character  were  included 
in  the  tests  made  by  the  New  York  Building  Bureau. 

The  construction  used  by  the  Metropolitan  Fireproofing  Com- 
pany consisted  of  a  combination  of  solid  partition  blocks  and 
metal  clips.  The  blocks  were  made  2  inches  thick,  of  a  mixture 
of  plaster  of  Paris  and  shavings.  The  top  and  bottom  edges  of 
the  blocks  were  rabbeted  on  each  side  so  as  to  reduce  the  thick- 
ness of  the  blocks  to  about  1-J  inches,  and  on  to  these  rabbets  or 
grooves  were  slipped  H-shaped  iron  clips,  at  the  tops  and  bottoms 
of  all  vertical  joints. 

Two  partitions  were  tested,  one  being  as  described  above, 
the  other  made  of  12  by  12  by  If-inch  blocks  connected  by  a 
different  clip.  The  latter  partition  " deflected  about  4  inches 
under  the  heat,  and  a  considerable  area  was  knocked  out  by  the 
hose  stream.  The  other  partition  withstood  the  test.  The 
plaster  had  been  destroyed  and  the  blocks  had  calcined  to  a 
depth  of  about  J  inch;  the  metal  clips  were  effective." 

The  "Norman"  partition  consisted  of  blocks  36  inches  by 


406         FIRE    PREVENTION    AND    FIRE    PROTECTION 

12  inches  by  2  inches  thick,  made  of  2  parts  plaster  of  Paris, 
1  part  wood  fiber,  and  a  small  quantity  of  cocoanut  fiber  for 
strength.  In  alternating  horizontal  joints  were  placed  A-inch 
round  rods  with  turnbuckles,  while  in  the  vertical  joints,  made 
continuous  from  floor  to  ceiling,  were  placed  l|-inch  by  J-inch 
bar-iron  stiffeners.  In  one  partition  the  blocks  were  laid  hori- 
zontally, in  the  other  vertically.  The  fire  and  water  test  caused 
the  destruction  and  washing  away  of  the  material  to  depths 
averaging  about  f  inch.  "In  no  place  had  the  fire  or  water 
passed  through  the  partition,  and  the  portions  of  the  blocks 
not  washed  away  were  in  good  condition." 


FIG.  105.  —  "  Phoenix  "  Braced  Tile  Partition. 

Similar  partitions  constructed  by  the  Sanitary  Fireproofing 
and  Contracting  Company,  consisted  of  2-inch  and  3-inch  plaster 
of  Paris  and  cinder  blocks,  with  concave-grooved  edges.  The 
blocks  were  also  pierced  with  small  holes  to  allow  the  placing  of  a 
metal  rod  dowel  in  each  vertical  joint,  and  two  continuous  metal 
rods  from  floor  to  ceiling  in  each  block  length.  In  the  test,  the 
material  was  calcined  and  washed  away  to  a  depth  of  about  i  inch. 

Among  the  1901  tests  of  the  New  York  Building  Bureau  were 
two  types  of  metal-braced  tile.  One  construction  was  known  as 
the  Brinkman  partition.  It  consisted  of  solid  tile  blocks,  one 
test  being  of  2  by  9J  by  15J-inch  blocks,  the  other  of  1 J  by  10  by 
16 i-inch  blocks.  In  both  cases  the  horizontal  joints  were  rein- 
forced by  means  of  special  stamped  H-shaped  metal  members  (the 
courses  of  blocks  fitting  into  the  grooves),  which  were  in  turn 
supported  by  metal  uprights  placed  7  feet  6  inches  apart.  The 
horizontal  reinforcing  H's  were  protected  by  the  finished  plaster- 
ing. After  the  fire  and  water  test  "it  was  found  that  most  of 
the  plaster  coat  had  come  off  of  both  partitions,  but  that  the 


FIRE-RESISTING    PARTITIONS  407 

metal  work,  except  for  a  slight  deflection  in  places,  was  intact, 
and  that  the  blocks  had  suffered  no  injury  from  the  fire  and  water. 
In  no  place  had  the  fire  passed  through  the  partition." 

The  other  type  is  known  as  the  " Phoenix"  partition,  manu- 
factured by  Henry  Maurer  &  Son.  This  consists  of  porous 
terra-cotta  blocks,  12  by  9  by  2  inches,  laid  so  as  to  break  vertical 
joints.  The  long  edges  of  the  blocks  are  slightly  grooved  in 
order  that  the  horizontal  joints  may  be  reinforced  by  means  of 
band  iron  |  inch  wide,  which  is  embedded  in  the  mortar  joint 
(see  Fig.  105).  The  only  effect  of  the  fire  and  water  test  was 
to  calcine  and  wash  away  some  of  the  plastering. 

A  similar  construction  is  made  by  the  National  Fire  Proofing 
Company  under  the  name  of  the  "New  York"  reinforced  par- 
tition, Bevier  patent.  Two-inch  hollow  blocks  are  used,  rein- 
forced in  the  horizontal  joints  with  a  woven- wire  truss,  similar 
to  that  used  in  the  "New  York"  floor  arch. 

Concrete  Partitions.  —  Solid  stone-  and  cinder-concrete  par- 
titions have  been  used  to  a  very  limited  extent  in  fire-resisting 
buildings,  and  their  use  is  not  liable  to  be  very  extended,  even  in 
this  age  of  concrete  construction,  on  account  of  the  disadvantages 
of  expense,  weight  and  erection.  Whether  made  of  stone 
concrete  or  cinder  concrete,  such  partitions  would  require  rein- 
forcement to  keep  the  thickness  within  reasonable  bounds,  and 
also  forms  for  erection  purposes.  These  items  add  considerably 
to  the  expense.  If  made  of  stone  concrete  the  weight  is  con- 
siderable, while  even  if  made  of  the  cheaper  and  lighter  cinder 
concrete,  the  weight  and  trouble  of  erection  are  still  objection- 
able. Even  in  all-concrete  buildings  the  partitions  are  fre- 
quently made  of  some  other  type.  Thus  in  the  sixteen-story 
reinforced-concrete  Ingalls  Building  in  Cincinnatti,  Mackolite 
partitions  were  employed  for  all  of  the  minor  divisions. 

A  few  partitions  of  reinforced  concrete  were  found  in  several 
of  the  firepoof  buildings  in  San  Francisco,  but  scarcely  in  suf- 
ficient quantities  to  warrant  comparisons  and  final  conclusions. 
In  every  case  they  developed  good  fire-resistance,  and  remained 
in  much  better  condition  after  normal  fires  of  one-half  hour 
to  one  hour  duration  than  either  metal  lath  and  plaster  or  tile. 
The  behavior  of  the  reinforced-concrete  partitions  was  entirely 
satisfactory,  and  it  is  probable  that  partitions  of  this  type  4 
inches  to  6  inches  in  thickness  will  fulfill  all  ordinary  require- 
ments in  fireproof  buildings.* 

*  See  The  4tSan  Francisco  Earthquake  and  Fire,1'  by  A.  L.  A.  Himmelwright, 
C.  E. 


408         FIRE   PREVENTION   AND   FIRE    PROTECTION 

A  concrete-block  partition  was  among  those  tested  by  the  New 
York  Building  Bureau.  This  was  known  as  the  Sprickerhoff 
partition.  It  was  made  of  concrete  blocks  27  by  12  by  3  inches 
in  size,  composed  of  1  part  Portland  cement,  1  part  sand  and 

5  parts  steam  ashes.     The  blocks  were  laid  broken  joint,  in 
mortar  made  of  1  part  cement  to  2  parts  sand.     The  top  edges 
of  the  blocks  were  tongued,  and  the  lower  edges  grooved,  thus 
making  all  horizontal  joints  tongue  and  groove  for  added  strength. 
To  give  still  greater  stiffness,  pieces  of  strap  iron  1  inch  wide  by 

6  inches  long  were  placed  in  the  horizontal  joints  at  both  top 
and  bottom  of  every  vertical  joint,  and  to  permit  the  placing  of 
such  straps,  the  top  tongue  on  all  blocks  was  stopped  off  3  inches 
from  each  end.     "The  effect  of  the  fire  and  water  was  to  strip 
the  plaster  from  the  walls,  but  the  blocks  were  unharmed  and 
the  partitions  remained  as  straight  and  plumb  as  before  the 
test  began."     Hollow  concrete-  or  mortar-blocks  are  sometimes 
used  for  interior  partitions,  but  their  thickness  is  objectionable. 
Fire  tests  of  such  blocks  were  given  in  Chapter  VII. 

Sheathings,  etc.  —  Plaster  board,  made  of  gypsum  plaster 
and  wood  fiber,  in  thicknesses  from  J  to  1  inch,  has  been  used  to 
a  considerable  extent  for  furrings,  ceilings  and  partitions.  The 
widest  use  of  plaster  board  has  been  the  variety  known  as 
Sackett  Plaster  Board.  This  material  consists  of  three  layers  of 
gypsum  plaster  and  four  thin  layers  of  wool  felt,  the  outside 
surfaces  being  of  the  felt.  The  board  is  made  in  three  thick- 
nesses, i  inch,  f  inch  and  \  inch,  the  size  of  the  boards  being 
uniformly  32  by  36  inches. 

This  board  was  primarily  designed  as  a  substitute  for  wood 
lath.  It  is  light,  tough,  easily  cut  with  a  saw,  readily  applied 
to  studding,  etc.,  while  gypsum  plaster  adheres  perfectly  to  the 
board  without  key.  It  is  claimed  that  the  boards  will  not  warp 
or  twist,  and  that  a  minimum  of  plaster  is  required. 

The  J-inch  board  is  generally  used  for  lathing  partitions,  the 
f  inch  for  ceilings,  and  the  J  inch  for  either  purpose  when  par- 
ticularly good  work  is  desired. 

The  "Perfected  Brand,"  f  inch  thick,  when  fastened  in  place 
by  flat  headed  barbed-wire  nails  not  over  6  inches  apart  at  each 
support,  is  thus  classified  by  the  Underwriters'  Laboratories: 

"Tests  and  investigations  show  that  this  board  is  a  suitable 
base  for  fibered  gypsum  plasters,  and  when  attached  as  described 
to  walls  and  ceilings,  and  plastered,  its  fire-retard  ant  properties 


FIRE-RESISTING    PARTITIONS  409 

are  somewhat  higher  than  those  of  wooden  lath  and  fibered 
gypsum  plaster,  or  wooden  lath  and  lime  plaster,  in  buildings  in 
which  wooden  studding,  joists  and  furring  are  used;  but  these 
properties  are  not  sufficiently  higher  to  entitle  the  board  to  a 
materially  better  classification  as  a  fire-retardant." 

Gypsinite  Studding  consists  of  an  incombustible  stud,  to  be 
used  in  partition  work,  etc.,  instead  of  wood  studs.  It  is  com- 
posed of  gypsinite  concrete,  or  gypsum  and  wood  fiber,  reinforced 
by  two  ^-inch  by  2-inch  wood  nailing  strips  embedded  therein. 
These  studs  are  3  inches  square,  weighing  3  pounds  per  foot,  and 
are  furnished  in  stock  lengths  of  12  feet.  They  are  placed 
16  inches  centers,  and  are  braced  by  means  of  plate,  sill  and 
cross  bridging  of  the  same  material,  all  joints  being  made  by 
means  of  galvanized  sheet-iron  sockets.  When  covered  with 
Sackett  plaster  boards  and  plastered  each  side  with  gypsum 
plaster  laid  to  j-inch  grounds, 

tests  and  investigations  at  Underwriters'  Laboratories  show  that 
for  heights  not  exceeding  12  feet,  non-bearing  partitions  con- 
structed as  described  possess  somewhat  higher  fire-retard  ant 
properties  than  partitions  composed  of  wooden  studding  and 
wooden  lath  and  fibered  gypsum  plaster  or  lime  plaster;  but 
these  properties  are  not  sufficiently  higher  to  entitle  this  par- 
tition to  a  classification  for  corridor  and  room  partitions  in 
fireproof  buildings,  or  for  the  enclosure  of  important  vertical 
openings  through  buildings. 

Asbestos  Building  Lumber  has  been  described  in  Chapter  VII, 
page  263. 

Enclosures  of  Vertical  Openings.  —  For  partitions  around 
stair  wells  see  Chapter  XV,  particularly  paragraph  "  Enclosing 
Partitions,"  page  505.  For  partitions  around  elevator  shafts, 
see  Chapter  XVI,  especially  paragraph  " Solid  Enclosure  Walls," 
page  541. 

Wire  Glass  Partitions.  —  See  "  Metal  and  Wire  Glass  En- 
closures "  around  stairs,  Chapter  XV,  page  506,  also  "  Metal  and 
Wire  Glass  enclosures"  around  elevator  shafts,  etc.,  Chapter 
XVI,  page  542. 

Steel  Bucks.  —  All  openings  in  block  partitions,  whether 
plaster-block,  concrete-block  or  tile,  should  be  provided  with 
steel  "bucks"  or  frames.  These  may  be  made  of  angles,  tees 
or  channels,  as  shown  in  Fig.  106,  but  as  both  angles  and  tees 
require  the  cutting  of  the  blocks,  channels  are  the  most  practi- 
cal form.  The  channels  may  be  made  of  the  same  size  as  the 


410         FIRE    PREVENTION    AND    FIRE    PROTECTION 


thickness  of  the  block,  —  thus  4-inch  channels  for  4-inch  blocks 
—  in  this  case  requiring  a  slight  champf ering  of  the  edges  of  the 


FIG.  106.  —  Steel  Door  "Buck". 


blocks  so  as  to  fit  between  the  channel  flanges;  or  the  channels 
may  be  made  one  inch  wider  than  the  blocks.  The  latter 
method  is  shown  in  Fig.  107  which  illustrates  the  column  pro- 


3  T.-C.  Blocks 
Galv'd  Iron  Clamps 


6T.-C.  Blocks 


FIQ.  107.  —  Column  Covering  and  Partitions,  U.S.  Post  Office,  San  Francisco. 

tection  and  partition  construction  used  in  the  United  States 
Public  Building  at  San  Francisco.  The  partitions  are  made 
of  6-inch  tile  blocks  with  double  air  cells,  all  door  and  window 
openings  being  framed  with  7-inch  channels. 

The  bucks  should  run  the  full  story  height,  from  the  top  of 
floor  arch  to  the  under  side  of  arch  above.  They  should  be 
placed  as  soon  as  the  floor  arches  are  in.  Small  angle-iron  knees 
at  the  ends  of  the  uprights  are  drilled  or  clipped  to  the  flanges  of 
floor  beams  or  girders,  but  if  the  bucks  do  not  come  over  or  under 
floor  beams,  they  may  be  supported  by  light  horizontal  angles 
which  are  run  between  the  nearest  beams  —  or  the  end  knees 
may  be  lagged  directly  to  the  fire-resisting  arch.  Headers  or 
lintels  over  all  openings,  and  sill  pieces  under  windows,  should 
be  framed  in  between  the  uprights,  and  wherever  the  uprights 
have  partition  blocks  on  both  sides,  as  over  doors  or  under 
high-up  windows,  the  channel  uprights  should  be  double,  or  back 
to  back,  so  as  to  support  the  blocks  on  both  sides. 


FIRE-RESISTING    PARTITIONS 


411 


Fire-resisting  Partition  Trim.  —  In  the  first  paragraph  of 
this  chapter,  "Functions  of  Partitions,"  it  was  stated  that  "at 
least  95  partition  constructions  out  of  100  show  that  the  archi- 
tectural functions  of  partitions  are  utilized,  while  their  fire- 
resisting  functions  are  hardly  considered";  and  to  show  that  even 
reputable  fireproofing  companies  have  been  wholly  inconsistent, 
at  least  in  the  past,  regarding  proper  partition  construction,  the 
author  offers  Figs.  108  and  109  which  are  reproduced  direct 


Door 


iass 


SECTION 
THKOUGH  DOOR  ANo'TRANSOM  JAMB. 


Stop 

-Wood  Strip  Nailed  to 
Rough  Door  Jamb. 

All  Tile  to  be  Notched 
over  same. 


One  to  each  Block 


Space  for  Wires 


SECTION 
THROUGH  TRANSOM  HEAD 

FIGS.  108  and  109.  —  Wood  Frames  and  Trim  in  Partition  Construction. 

from  illustrations  in  one  of  the  older  catalogs  of  a  prominent 
terra-cotta  fireproofing  company.  These  were  presented  in  the 
catalog  as  typical  details  of  wood  frames  and  trim  around  doors 
and  windows  in  partitions.  They  should  have  been  labeled 
in  large  type  "How  not  to  do  it!" 

Manifestly,  as  before  stated,  fire-resisting  partitions  should 
not  contain  doors,  window  frames,  or  trim,  of  wood.  Fire- 
resisting  doors  and  windows  are  considered  at  length  in  Chaptsr 
XIV,  hence  attention  will  here  be  confined  to  fire-resisting  trim 
as  applied  to  partitions. 


412          FIRE    PREVENTION    AND    FIRE    PROTECTION 


Fire-resisting  trim  may  be  successfully  executed  in  fireproofed 
wood,  cement,  terra-cotta  or  metal. 


FIG.  110.  — Terra-Cotta  Partition  Trim,  —  Door  Architrave. 

Fireproofed  Wood,  described  at  length  in  Chapter  VII,  has  been 
used  to  some  extent  as  incombustible  trim,  especially  in  New  York 
City,  where  the  building  code  requires  that  all  buildings  exceetl- 
ing  twelve  stories  or  150  feet  in  height  shall  have  incombustible 
floors,  metal  or  metal-covered  window  frames  and  sash,  while 
"the  inside  window  frames  and  sash,  doors,  trim  and  other  in- 
terior finish  may  be  of  wood  covered  with  metal,  or  wood  treated 
by  some  process  approved  by  the  Board  of  Buildings  to  render 
the  same  fireproof/'  The  "Flat  Iron " 
or  Fuller  Building  affords  a  good  ex- 
ample of  the  use  of  fireproofed  wood 
for  partition  trim,  etc. 

Cement  Trim  has  been  successfully 
used  for  many  years  —  especially  in 
European  practice  —  for  running 
mouldings  such  as  door  architraves, 
window  trim  and  base  mouldings, 
etc.  Some  hard  plaster,  such  as 
Keene's  cement,  is  used,  and  almost 
any  open  moulding  may  be  "run"  of 
sharp  and  true  outline.  When  prop- 
erly done,  cement  trim  will  stand  or- 
dinary usage  for  a  long  time. 

Terra-cotta    Trim,   as    illustrated    in 
Figs.  110*  and  111,*  was  used  for  all 
partitions     in     the     "Amelia     Apart- 
Fio.  m.-Terra-Cotta  Par-      ments,"  built  at  Akron,  Ohio,  in  1901. 
tition  Trim,  — Base  and         Practically   the    entire    building    was 
Picture  Moulding.  constructed  of  hard    burned  vitrified 

terra-cotta.      Fig.   110  illustrates  the  specially  formed  tile  used 
for  all  door  architraves,  and  Fig.  Ill  illustrates  the  tile  block? 
*  See  Fireproof  Magazine,  July,  1903. 


FIRE-RESISTING   PARTITIONS 


413 


used  for  bases  and  picture  mouldings  in  partitions.  These  tiles 
were  afterwards  painted. 

Metal  Trim  may  be  made  of  cast-iron,  hollow  metal,  or  of 
sheet  metal  over  a  core  of  wood  or  other  material. 

Cast-iron  Trim.  —  For  thin  partitions  (either  plaster  or  blocks), 
cast-iron  door  or  window  frames  may  be  used  as  indicated  in 
Fig,  112. 


FIG.  112.  —  Cast-iron  Door  Frames  for  Thin  Partitions. 


Metallic  trim,  that  is,  hollow  metal  frames,  trim,  etc.,  and 
kalamine  trim,  or  sheet  metal  over  wood,  are  considered  more  at 
length  in  Chapter  XIV  in  connection  with  doors,  windows,  etc. 

Metal-covered  Concrete  Trim.  —  A  proposed  system  of  sheet- 
metal  trim  over  concrete  cores  or  backing  is  shown  in  Figs.  113* 
and  114.*  The  former  illustrates  door  frame  and  partition 


SECTION  OF  BASE  BOARDS 
FOR  TILE  PARTITION 


SECTION  OF  DOOR  FRAME 
TILE  PARTITION 


FIG.  113.  —  Metal-covered  Concrete  Trim. 

base  as  used  in  connection  with  a  tile  partition,  while  Fig.  114 

shows  a  proposed  arrangement  when  used  in  connection  with  a 

*  See  Architects'  and  Builders'  Journal,  May,   1906. 


414 


FIRE    PREVENTION    AND    FIRE    PROTECTION 


2-inch  solid-plaster  partition.     In  this  construction  the  partition 
is  built  to  the  trim  after  the  latter  is  in  place. 

Wire  Glass.  —  Where  glass  is  absolutely  required  in  fire- 
resisting  partitions,  whether  in  windows,  transoms,  or  door 
panels,  wire  glass  should  always  be  used.  The  Kohl  Building, 
burned  in  the  San  Francisco  fire,  was  provided  with  kalamine 


r — 3" 

TTONOF  DOOR  FRAME 

2"PARTITION 


SECTION  OF  BASE  BOARDS  AND 

CAP  FOR  PICTURE  MOULD 

AT  CEILING 


THRESHOLD 
FIG.  114.  — Metal-covered  Concrete  Trim. 

doors,  windows  and  trim  throughout  all  interior  partitions,  but 
in  combination  with  plate  glass.  The  kalamine  work  proved 
effective,  but  it  would  have  been  still  more  so  had  wire  glass 
been  used. 

Sound-proof  Partitions.  —  Where  sound-proof  partitions 
are  required  (as  in  music  studios,  etc.),  the  following  specifica- 
tions have  been  used  by  Messrs.  Holabird  &  Roche,  architects, 
Chicago:  "Lay  up  two  3-inch  hollow  tile  partitions,  set  abso- 
lutely isolated  from  each  other,  leaving  a  2-inch  air-space  between. 
In  this  air-space  shall  be  hung,  from  ceiling  to  floor,  strips  of 
corrugated  building  paper,  weighing  6  pounds  per  square  of  one 
hundred  feet,  perfectly  joined  at  the  joints,  and  continuous  from 
floor  to  ceiling." 

A  series  of  tests  undertaken  in  1895  by  Mr.  Dwight  H.  Perkins, 
architect,  to  determine  upon  the  sound-proofing  of  partitions 
in  the  Music  Building,  Chicago,  showed  that  a  double  teita- 


FIRE-RESISTING   PARTITIONS  415 

cotta  tile  partition,  made  of  two  3-inch  partitions  with  a  J-inch 
air-space  between,  gave  the  best  results. 

Similar  tests,  to  determine  partition  construction  in  the  dor- 
mitories of  the  New  England  Conservatory  of  Music,  Boston, 
were  made  by  Prof.  Charles  L.  Norton,  1902.* 

After  much   consideration,   the   writer  has  given  the  fol- 
lowing ratings  to  the  different  partitions.     The  order  of  their 
standing  upon  the  list  indicates  their  efficiency  as  compared 
with  those  above  and  below  them. 
Scale.  Composition. 

100.  ....  .Cabot's  quilt,  3  thick  +  metal  lath. 

95 Cabot's  quilt,  2  thick  -j-  metal  lath. 

95 Cabot's  quilt,  2  thick  +  metal  lath. 

85 Sackett  board,  2  felt  on  L  a. 

85 Sackett  board,  2  felt  on  C  s. 

80 Sackett  board,  2  felt. 

75 Metal  lath  +  paper. 

75 Metal  lath  -j-  paper  +  felt. 

60 Two  2-inch  Keystone  blocks  with  2  inch  air-space. 

50 4-inch  National  terra-cotta  blocks. 

50 3-inch  Keystone  blocks. 

45 3-inch  National  terra-cotta  blocks. 

40 2-inch  Keystone  blocks. 

40 2-inch  National  terra-cotta  blocks. 

30 2-inch  metal  lath  and  solid  plaster. 

Nothing  more  is  to  be  inferred  from  the  numerical  effi- 
ciencies than  that  the  first  partition  is  about  three  times  as 
good  as  the  last,  and  that  the  numerical  interval  between  any 
two  partitions  on  the  list  merely  indicates  the  order  of  magni- 
tude of  the  difference  between  the  partitions. 

The  efficiency  of  the  Cabot  quilt,  as  a  material  for  render- 
ing the  partition  ' sound-proof,'  is  so  clearly  demonstrated  in 
these  tests  that  I  recommend  it  for  use  in  the  partitions  for 
which  these  tests  were  made.  The  nature  of  the  material  in 
which  the  quilt  is  encased  should  be  carefully  considered.  I  do 
not  think  it  within  the  province  of  this  report  to  discuss  the 
partition  "from  other  than  acoustic  considerations,  and  as  an 
encasing  medium  the  most  effective  material  is  Sackett  board 
and  adamant  plaster. 

I  would,  therefore,  give  as  my  opinion  that  the  best  acoustic 
results  would  be  attained  by  using  a  partition  of  Sackett  board 
and  plaster  with  two  thicknesses  of  Cabot's  quilt  between  the 
plaster  board.  .  .  . 

As  later  tests  showed,  some  sort  of  suspended  ceiling  will 
be  needed,  as  the  concrete  slab  transmits  the  sound  across  the 

*  For  complete  report,  see  Report  No.  II,  "Sound-proof  Partitions," 
Insurance  Engineering  Experiment  Station. 


416         FIRE   PREVENTION   AND   FIRE   PROTECTION 

top  of  the  partition  readily.  No  trouble  will  be  given  by  the 
sound  passing  through  the  concrete  to  the  rooms  above  or 
below;  but,  unless  a  layer  of  Cabot's  quilt,  with  under  lath  and 
plaster,  or  of  Sackett  board  and  plaster  be  put  on  the  under  side 
of  the  concrete  ceiling,  the  efficiency  of  the  partitions  will  be 
diminished  somewhat. 

Conclusions.  —  Tests  show  conclusively  that  satisfactory 
fire-resisting  partitions  can  be  built. 

Experience,  in  actual  fires,  shows  that  poor  design  and  poor 
workmanship  are  responsible  for  most  failures. 

Essentials,  proper  planning,  design,  materials,  workmanship. 

Planning.  —  The  whole  scheme  of  fire- resistance  should  be 
considered,  in  an  effort  to  localize  incipient  fire,  surround  bad 
risks,  and  also  to  make  wide-spread  fire  impossible.  Minimize 
openings. 

Design  requires  adequate  thickness  and  stability,  and  fire- 
resisting  doors,  windows  and  trim.  Metal  bucks  are  desirable 
at  all  openings.  All  partitions  to  be  independent  of  column 
coverings. 

Materials.  —  Sheathing 's  are  usually  incombustible  only,  not 
fire-resistive. 

Metal  Lath  and  Plaster.  —  Some  tests  of  plaster  partitions  in 
actual  fires  have  shown  such  constructions  to  be  reliable  under 
fairly  severe  conditions,  while  other  tests  have  proved  their 
inefficiency.  There  is,  therefore,  a  decided  difference  of  opinion 
regarding  their  use,  but  a  sufficient  number  of  marked  failures 
have  been  recorded  to  show  conclusively  that  plaster  construc- 
tion cannot  be  considered  first-class  fireproofing.  Indeed,  where- 
ever  plaster  has  been  depended  on  for  fire-resistance,  whether 
in  combination  with  brick,  tile,  wire  lath  or  metal  lath,  it  appears 
that  sufficient  bond  has  not  existed  between  the  plaster  and  the 
surface  to  which  it  was  applied  to  resist  successfully  the  combined 
action  of  fire  and  water. 

Plaster-block  partitions  possess  good  qualities,  but  calcine  under 
heat  and  wash  away  under  hose  streams  to  such  an  extent  as 
generally  to  make  renewal  necessary. 

Tile  partitions  will  constitute  the  most  satisfactory  light-weight 
partitions  if  made  of  semi-porous  or  porous  material.  They 
should  be  made  thicker  than  generally  used,  and  particular  atten- 
tion should  be  paid  to  workmanship. 

Concrete  is  efficient,  but  heavy  and  difficult  to  install. 


FIRE-RESISTING    PARTITIONS  417 

Brick  is  highly  efficient  and  should  be  used  for  main  dividing 
fire  walls,  around  stairs  and  elevator  shafts,  and  where  particu- 
larly severe  conditions  are  to  be  expected. 

Workmanship.  —  Partitions  must  be  started  on  fire-resisting 
floors,  wedged  at  ceilings,  braced  to  masonry  walls,  and  laid  in 
cement  mortar.  Piping  should  never  be  cut  into  partitions,  but 
should  be  placed  in  especially  designed  chases  or  slots. 


CHAPTER  XIV. 

FIEE-RESISTING    SHUTTERS,   WINDOWS   AND 
DOORS. 

Note.  —  The  detailed  standard  rules  and  requirements  of  the  National  Board 
of  Fire  Underwriters  concerning  Fire  Doors,  Shutters  and  Wire  Glass  Windows, 
etc., — viz.,  the  booklet  "Fire  Doors  and  Shutters"  containing  many  illus- 
trations of  Doors,  Shutters,  Frames,  etc.,  and  booklet  "Wired  Glass"  —  may 
be  obtained  gratis  by  addressing  the  National  Board  of  Fire  Underwriters, 
135  William  St.,  New  York  City. 

Exposure  Hazard  generally  constitutes  one  of  the  most 
difficult  problems  of  fire  protection,  in  securing  a  proper  balance 
between  theoretical  requirements  and  sensible  practice.  As  was 
found  to  be  the  case  with  interior  fire-resisting  partitions,  it  is 
evident  that  the  architectural  functions  of  window  and  door 
openings,  whether  in  exterior  walls  or  in  interior  walls  or  par- 
titions, are  generally  considered  of  far  more  importance  than 
their  fire-resisting  functions,  in  spite  of  the  fact  that  such  open- 
ings almost  invariably  constitute  the  weakest  link  in  the  chain 
of  fire  protection  as  applied  to  building  construction.  Indeed, 
the  experiences  of  Baltimore  and  San  Francisco  are  liable  to 
be  duplicated  or  even  exceeded  at  any  time,  owing  to  the  wide 
neglect  of  exposure  precautions. 

A  fire-resisting  building  has  been  defined  as  one  which  would 
confine  fire  of  interior  origin  to  the  unit  of  area  within  which  it 
started,  and  also  as  one  which  would  protect  itself  and  its  con- 
tents against  adjacent  or  exterior  fire,  even  though  of  severe  and 
wide-spread  intensity.  This  external  hazard  is  quite  as  impor- 
tant, indeed  often  very  much  more  important,  than  the  danger 
against  interior  fire;  for  the  burning  of  an  adjacent  or  nearby 
structure  or  structures  is  almost  sure  to  produce  test  conditions 
of  far  greater  severity  than  those  which  could  possibly  arise 
within  a  building  in  which  the  proper  subdivision  of  areas  and 
the  treatment  of  vertical  openings  had  been  considered. 

The  efficiency  of  any  exterior  wall  under  fire  test  will  vary 
inversely  as  the  number  and  the  size  of  the  openings  in  such  wall. 
No  construction  can  prove  a  more  reliable  fire  stop  than  a  brick 

418 


FIRE-RESISTING    SHUTTERS,    WINDOWS   AND    DOORS      419 

wall  of  adequate  thickness  and  rigidity,  but  without  openings. 
Such  blank  walls,  however,  are  generally  limited  to  party  or 
side  walls,  abutting  adjacent  property,  where  windows  cannot, 
of  necessity,  be  introduced.  For,  modern  requirements  of  a 
maximum  of  light  and  air  in  office  or  other  commercial  or  resi- 
dential buildings  usually  demand  that  windows  be  provided  in 
all  exterior  walls,  where  possible;  and  even  party  or  side  walls, 
in  case  the  new  structure  is  built  to  a  greater  height  than  the 
older  adjacent  building,  are  often  pierced  with  windows  over- 
looking the  neighboring  property. 

In  fact,  it  was  just  such  a  case  which  first  directed  prominent 
attention  to  the  external  hazard  from  adjacent  property,  viz., 
the  fire  which  resulted  in  such  great  damage  to  the  Home  Life 
Insurance  Company's  Building  in  1898,  as  described  in  Chap- 
ter VI.  Here  was  a  building  designed  to  be  thoroughly  fire- 
resisting,  in  which  an  internal  fire  would  undoubtedly  have  been 
confined  to  the  floor  of  origin  without  serious  damage  to  the 
building  as  a  whole.  But  the  neglect  to  provide  fire-resisting 
window  openings  in  the  side  wall  and  light-court  adjacent  to  and 
overlooking  the  Rogers,  Peet  &  Co.'s  clothing  store  was  the 
direct  cause  of  a  heavy  fire-  and  water-damage  to  almost  the  en- 
tire building. 

Determining  Factors.  —  The  use  to  which  the  building  is  to 
be  put  will  often  influence  or  determine  the  number  and  size  of 
the  window  openings.  The  office  building  demands  a  maximum, 
both  in  number  and  size;  while  the  storage  warehouse,  intended 
by  its  very  architectural  design  to  express  assurance  as  to  the 
safety  of  its  contents,  is  usually  provided  with  few  window 
openings,  and  even  those  of  very  limited  area. 

The  general  location  of  any  particular  structure,  the  character 
of  its  contents  and  its  proximity  to  neighbors  of  dangerous  con- 
struction, contencs,  or  manufacturing  processes,  will  all  be  deter- 
mining factors  in  deciding  upon  the  degree  of  fire-resistance  which 
it  may  be  necessary  to  provide  in  the  window  openings  called 
for  by  the  design. 

If  our  congested  city  areas  of  large  and  high  mercantile  build- 
ings were  uniformly  of  fire-resisting  construction,  there  would 
be  far  less  need  of  window  protection  than  now  generally  exists. 
It  is  the  usual  promiscuous  mingling  of  both  good  and  bad  con- 
struction that  lends  such  an  element  of  danger  to  the  former 
through  the  shortcomings  of  the  latter.  Hence  a  building  in- 


420         FIRE    PREVENTION    AND    FIRE    PROTECTION 

tended  to  be  thoroughly  fire-resisting  must  provide  added  pre- 
caution, and  consequently  incur  added  expense,  to  overcome 
the  hazard  occasioned  by  some  more  shortsighted  owner  who 
builds  for  his  own  convenience  only,  regardless  of  his  duty  to 
neighbors  or  the  community.  Therein  lies  a  great  injustice 
resulting  from  our  building  laws  which  permit  good,  bad  and 
indifferent  constructions  within  one  and  the  same  locality. 

Wall  Exposures.  —  Hence,  under  present  conditions  obtaining 
in  all  large  cities,  it  is  still  necessary  or  desirable  to  provide  fire- 
resisting  window  frames  and  sash,  even  for  building  facades  on 
public  squares  or  parks  (unless  of  very  extensive  area),  or  upon 
wide  avenues  or  streets,  owing  to  the  danger  arising  from  the 
lodgment  of  flying  sparks  or  firebrands  against  the  exterior  win- 
dow trim  during  a  conflagration  of  any  great  severity.  This 
grave  danger  to  an  otherwise  impregnable  building  was  clearly 
demonstrated  in  the  Baltimore  conflagration,  where  burning 
sparks  from  the  surrounding  non-fire-resisting  buildings  fell  in 
sufficient  quantities  upon  the  window  sills  of  the  Continental 
Trust  Company's  Building  to  ignite,  almost  simultaneously,  the 
window  frames  and  sash  of  nearly  all  of  the  upper  stories. 

For  such  exposures,  fronting  upon  parks,  open  squares,  or  even 
upon  very  wide  thoroughfares,  it  would  be  sufficient  to  provide 
some  type  of  non-combustible  window  trim,  possibly  hollow 
metal  or  kalamine  frames  and  sash,  with  plate-glass  lights,  es- 
pecially if  the  building  were  equipped  with  means  of  fighting 
fire  upon  each  and  every  floor,  as  should  invariably  be  the  case, 
regardless  of  how  efficiently  the  scheme  of  fire-resistance  may  be 
carried  out. 

Thus  in  the  Home  Life  Insurance  Company's  Building,  before 
mentioned,  there  was  little  or  no  necessity  for  providing  either 
fire  shutters  or  fire-resisting  windows  of  the  highest  efficiency  on 
the  principal  facade,  as  the  building  fronts  on  Broadway,  imme- 
diately opposite  City  Hall  Park.  This  would  make  direct  con- 
flagration hazard  slight  from  that  direction.  But  for  the  side 
and  court  windows,  overlooking  lower  and  non-fire-resisting 
buildings  containing  highly  inflammable  contents,  there  was 
every  practical  reason  for  providing  a  high  degree  of  fire-resist- 
ance in  the  wall  openings. 

Windows  on  narrow  streets,  whether  front,  rear  or  side,  win- 
dows on  alleys  or  courts,  those  overlooking  adjacent  property, 
should  all  be  rendered  fire-resistive  to  the  degree  suggested  by 


FIRE-RESISTING    SHUTTERS,    WINDOWS   AND   DOORS      421 

the  nearness  or  character  of  the  adjacent  buildings  or  their  con- 
tents. For  very  near  or  very  severe  exposures,  some  form  of 
fire-resisting  shutter  combined  with  a  fire-resisting  window 
construction  behind  it,  is  undoubtedly  the  best  protection.  For 
less  severe  exposures  some  of  the  window  types  to  be  mentioned 
later  will  probably  suffice. 

Building  Ordinances.  —  The  question  of  window  protection 
is  often  determined  by  the  local  building  ordinance.  Thus  the 
requirements  of  the  New  York,  Cleveland  and  other  ordinances 
are  similar  to  the  Boston  law  which  is  as  follows: 

In  all  first-  or  second-class  mercantile  or  manufacturing 
buildings  over  thirty  feet  in  height,  outside  openings  in  party 
walls,  or  in  any  rear  or  side  wall  within  twenty  *  feet  of  an  oppo- 
site wall  or  building,  shall  have  metal  frames  and  sashes  and 
shall  be  glazed  with  wire  glass  or  shall  be  protected  by  shutters. 
Such  shutters  shall  be  covered  on  both  sides  with  tin  or  shall  be 
made  of  other  suitable  fireproof  material,  and  hung  on  the  out- 
side, either  upon  independent  metal  frames  or  upon  metal 
hinges  attached  to  the  masonry,  and  shall  be  made  to  be  han- 
dled from  the  outside,  and  one  such  shutter  in  each  room  shall 
have  a  protected  hand  hole  eight  inches  in  diameter. 

The  Building  Code  recommended  by  the  National  Board  of 
Fire  Underwriters,  in  view  of  late  experience  in  conflagrations, 
etc.,  goes  much  farther  in  the  matter  of  window  protection,  as 
follows : 

Every  building,  except  private  dwelling-houses  and 
churches  shall  have  standard  window  protection  —  viz.,  shut- 
ters or  metal  and  wire  glass  windows  —  on  every  exterior  window 
and  opening  above  the  first  story,  excepting  on  the  front  open- 
ings of  buildings  fronting  on  streets  which  are  more  than  one 
hundred  feet  in  width,  or  where  no  other  buildings  are  within 
one  hundred  feet  of  such  openings. 

Auto  Exposure  is  the  danger  or  exposure  a  building  offers  to 
itself  through  the  possibility  of  communicating  fire  from  story  to 
story  by  means  of  the  window  openings,  much  the  same  as  fire 
may  be  communicated  internally  through  vertical  openings.  All 
windows  occurring  in  successive  stories  offer  more  or  less  auto 
exposure,  but  openings  in  indented  courts  or  in  interior  light- 
wells,  etc.,  are  particularly  dangerous  in  this  regard,  as  such 
courts  or  shafts  are  especially  liable  to  act  as  flues,  thus  aggravat- 
ing the  intensity  and  upward  rush  of  flames.  The  Chicago 

*  Thirty  feet  in  New  York  and  Cleveland  laws. 


422         FIRE    PREVENTION   AND   FIRE    PROTECTION 

Athletic  Club  Building  and  the  Asch  Building  fires  offered  ex- 
cellent examples  of  auto  exposure,  in  the  communication  of  fire 
from  the  windows  of  lower  stories  into  the  windows  of  upper 
stories. 

Experience  from  Various  Fires.  —  Before  considering  the 
present  most  approved  methods  of  window  protection,  it  will  be 
profitable  to  review  briefly  the  experience  gained  in  past  files. 

Prior  to  the  year  1904,  numerous  fires  in  individual  buildings 
had  served  to  call  attention  to  the  necessity  for  window  pro- 
tection against  dangerous  neighbors  or  against  existing  hazards 
of  various  character,  as  has  been  pointed  out  in  Chapter  VT. 

Thus  the  first  fire  in  the  Home  buildings  in  Pittsburgh  was 
essentially  an  exposure  fire,  —  very  severe,  it  is  true,  owing  to 
the  falling  walls  of  the  building  where  the  fire  originated  —  but 
efficient  window  protection  would  probably  have  furnished  the 
breastworks  behind  which  the  fire  department  could  have  fought. 

The  Vanderbilt  Building  was  provided  with  iron  shutters, 
but  as  none  of  them  was  closed,  a  severe  exposure  fire  resulted 
from  the  burning  of  a  non-fire-resisting  neighbor. 

The  Home  Life  Insurance  Company's  Building  fire  has  already 
been  mentioned.  The  Granite  Building  fire  in  Rochester,  de- 
scribed in  Chapter  VI,  demonstrated  the  utmost  disregard  on 
the  part  of  the  owners  concerning  this  great  hazard. 

Baltimore  Experience.  —  It  was  not  until  the  great  Balti- 
more conflagration  that  the  true  value  of  universal  window  pro- 
tection became  fully  apparent  —  a  protection  to  serve  not  only 
the  individual  building  to  which  it  was  applied,  but  to  serve  also 
the  interests  of  ail  adjoining  and  surrounding  structures  in  just 
so  far  reducing  the  conflagration  hazard.  In  a  special  report  on 
the  Baltimore  fire,  the  National  Fire  Protection  Association 
stated  as  follows: 

The  general  absence  of  protection  at  exposed  wall  openings  is 
responsible  for  the  spread  of  this  conflagration  more  than  any  other 
cause.  In  fact,  this  condition  may  be  safely  stated  to  have  been  the 
cause  for  the  spread  of  this  fire  beyond  fire  department  control. 

The  use  of  standard  fire  shutters  and  doors,  wired  and  prism 
glass  in  substantial  metallic  frames  designed  to  withstand  severe 
fire  conditions,  is  essential  not  only  as  a  protection  of  single 
properties,  but  as  a  means  of  preventing  conflagrations  in  all 
congested  districts  where  large  groups  of  buildings  are  mutually 
exposed  through  necessary  wall  openings. 

This  conflagration  has  again  demonstrated  that  where  sub- 
jected to  exposing  fire  the  most  vulnerable  parts  in  buildings  of 


FIRE-RESISTING    WINDOWS,    SHUTTERS    AND    DOORS      423 

fire-resistive  construction  are  the  window  and  wall  openings. 
The  necessity  for  making  all  these  openings  as  nearly  equal  to 
the  other  features  of  the  building  in  fire-resistive  properties  as 
is  possible  will  b3  apparent.  It  is  believed  that  the  proper 
application  of  the  devices  above  mentioned  will  attain  this  end. 
This  should  include  street  windows- 
See  also  Chapter  IX,  page  304. 

In  addition  to  these  general  deductions,  specific  instances  of 
the  value  of  fire-resisting  windows  were  brought  to  public  notice 
through  the  Baltimore  fire,  notably  by  the  metal  frame  and  wire 
glass  windows  in  the  " Electric  Transformer  Station,"  where 
such  windows  effectually  blocked  the  path  of  the  conflagration, 
not  only  protecting  the  building  referred  to,  but  limiting  the 
spread  of  fire  beyond. 

Tests  of  tin-covered  and  plate-iron  shutters  in  the  Baltimore 
fire  are  considered  in  more  detail  in  later  paragraphs. 

San  Francisco  Experience.  —  One  of  the  most  compre- 
hensive reports  on  the  question  of  window  protection,  etc.,  as 
exhibited  in  the  San  Francisco  conflagration,  is  to  be  found  in 
the  report  of  Mr.  S.  Albeit  Reed,  Consulting  Engineer  to  the 
Committee  of  Twenty,  of  the  National  Board  of  Fire  Under- 
writers, from  which  the  following  extracts  are  taken  as  being 
worthy  of  especial  consideration,  and  as  bearing  intimately  on 
the  details  discussed  in  this  chapter. 

Metal-covered  Trim.  —  The  Kohl  Building  afforded  the  first 
conflagration  experience  with  metal-covered  or  kalamine  interior 
and  window  trim.  The  windows  were  plate  glass,  and  partition 
glazing  ordinary  glass.  The  building  made  an  excellent  showing. 

Caution  must  be  exercised  in  drawing  broad  conclusions 
from  this  case.  The  fact  that  the  majority  of  the  plate  glass 
windows  are  not  even  cracked  shows  that  the  upper  floors  did 
not  receive  any  severe  shock.  The  building  was  not  deserted 
during  the-  fire.  Furthermore,  the  lower  three  floors  are  ex- 
tensively burned  out,  the  wood  having  ignited  under  its  metal 
sheathing,  showing  that  when  the  glass  of  windows  breaks  and 
fire  takes  hold  of  the  contents  of  the  room  the  heat  soon  pene- 
trates the  thin  metal  sheathing  of  the  trim.  Still,  there  is  a 
definite,  though  small,  advantage  in  this  detail  of  protection.  .  .  . 
There  are  places,  especially  in  a  region  of  fireproof  buildings, 
where  the  prevalent  cause  of  ignition  is  not  the  general  drift  so 
much  as  sparks  and  brands  which  lodge  on  window  sills  and 
ignite  the  sash  frames.  .  .  .  There  will  be  many  places  where 
the  temperatures  are  just  in  the  margin  short  of  the  point  where 
plate  glass  will  break,  but  above  the  point  where  exposed  and 


424         FIRE   PREVENTION    AND    FIRE    PROTECTION 

painted  wood  will  ignite.  In  these  cases  the  fact  that  the  trim 
is  metal  covered  may  turn  the  scale.  .  .  . 

Going  higher  in  the  scale  of  window  protection,  we  have 
the  case  of  the  Western  Electric  Company's  Building  (see 
later  reference  to  "  Wire  Glass  Windows  in  San  Francisco  Fire"), 
with  its  wire  glass  windows.  These  still  cannot  be  regarded 
as  standard,  inasmuch  as  the  defect  well  known  to  fire-protec- 
tion engineers,  namely,  diathermanency,  developed  the  antic- 
ipated effects,  namely  ignition  through  the  glass.  It  is  impor- 
tant not  to  be  misled  as  to  the  lessons  of  this  instance.  The 
breakdown,  at  the  start,  of  their  fine  private  equipment  for 
fire  defence  left  the  occupants  with  but  slight  advantage  over 
other  buildings  in  the  sweep  of  the  conflagration.  Their  mill 
construction,  automatic  sprinklers,  yard  reservoir  and  outside 
hydrants  did  not  save  them.  It  was  the  retardant  though  not 
positively  resistant  effect  of  the  wire  glass  and  metal-frame 
window  protection  which  gave  the  small  force  of  two  or  three 
men  a  chance  to  take  care  of  50  or  60  windows  and  extinguish 
ignition  fires  in  detail.  .  .  . 

Fire  Shutters.  —  As  before  referred  to,  there  were  no 
chances  to  observe  the  legitimate  action  of  fire  on  shutters 
because  in  nearly  every  case  the  fire  got  in  elsewhere  and  attacked 
the  shutters  from  the  inside.  Several  walls  were  standing, 
however,  with  tin-covered  shutters  still  hanging  at  their  window 
openings,  apparently  sound. 

Old-fashioned  inside  folding  iron  shutters  deserve  credit 
in  several  cases.  The  two  lower  floors  of  the  Mint  were  pro- 
tected with  them,  and,  though  the  glass  in  the  sash  was  de- 
stroyed, the  shutters  appear  to  have  been  uninjured.  In  the 
old  non-fireproof  warehouse  block  which  survived  to  the  west  of 
the  custom  house,  the  buildings,  2  or  3  stories  high,  were  nearly 
all  furnished  with  inside  folding  iron  shutters  to  all  windows, 
front  as  well  as  rear.  These  shutters  appear  uninjured,  although 
much  glass  is  broken.  The  fact,  however,  that  many  glass  win- 
dows on  this  block  were  not  broken  indicated  that  the  fire  con- 
ditions at  this  point  must  have  been  rather  mild;  yet  doubtless 
these  shutters  were  of  value.  The  same  argument  may  be  used 
here  as  was  used  in  the  case  of  the  metal-sheathed  window  trim, 
viz.,  that  many  instances  occur  in  conflagrations  where  even  a 
quite  inferior  window  protection  will  turn  the  scale.  In  the 
Bush  Street  Telephone  Exchange  the  windows  on  the  narrow 
front  on  Bush  street  were  of  ordinary  glass  and  had  outside 
rolling  steel  shutters.  In  places  the  window  glass  is  melted  into 
a  mass  on  the  window  sill,  while  the  shutters  are  apparently  un- 
injured. The  destructive  fire  here  was  the  internal,  not  the 
external,  yet  it  .is  plain  that  these  shutters  stood  a  heat  which 
reached  the  melting  point  of  glass,  viz.,  over  2000°  F.  The 
inside  tin-covered  wooden  shutters  are  heavily  bulged  and 
sprung  inward  from  the  effects  of  the  fire  inside  the  building. 
The  outside  wire  glass  with  metal-covered  sash  is  practically 
uninjured,  except  in  one  case,  where  the  shutter  had  bulged 


FIRE-RESISTING   WINDOWS,    SHUTTERS   AND   DOORS      425 

inward  and  exposed  the  wire  glass.  At  this  point  the  wire  glass 
has  sagged  6  inches  and  pulled  partly  out  of  the  sash  frame. 
In  the  Mission  Street  Telephone  Exchange  wire  glass  in  metal- 
covered  frames  without  shutters  saved  the  two  lower  floors, 
although  the  building  was  abandoned.  This  building  had  the 
advantage  of  being  in  a  scattered  frame  district  where  the  ex- 
posure, though  intense,  was  of  short  duration.  The  reinforced- 
concrete  floor  arches  and  the  protected  floor  openings  prevented 
the  fire  from  working  down  below  the  top  story.  The  ignition 
of  the  top  story  may  have  occurred  through  a  break  in  the  side 
wall,  at  a  point  near  the  roof,  caused  by  the  earthquake,  or 
there  may  have  been  ignition  through  the  glass  of  the  windows. 
It  is  a  unique  experience  for  an  abandoned  building  to  save,  in 
habitable  condition,  two  floors,  in  a  clean-swept  district,  solely 
by  the  excellence  of  its  window  protection  and  its  floor  con- 
struction. ... 

Deductions.  —  The  results  point  to  the  importance  of 
sub-standard  as  well  as  standard  window  protection,  as  an 
encouragement  to  men  to  remain  in  and  make  an  effort  to  save 
the  threatened  building.  The  number  of  city  buildings  in 
which,  for  reasons  of  economy  and  convenience,  it  will  be  pos- 
sible to  secure  sub-standard  front  window  protection  will  prob- 
ably be  large  compared  to  the  number  of  those  in  which  owners 
can  be  induced  to  install  protection  of  the  highest  standard. 

The  plan  of  a  double  line  of  defence  has  great  merit.  Two 
or  more  semi-pervious  screens,  one  behind  the  other,  may  be 
better  than  a  single  nearly  impervious  screen. 

Types  of  Window  Protection.  —  Considering  now  the 
various  types  afforded  by  current  practice,  it  will  be  found  that 
all  methods  of  fire-resistance  for  windows  may  be  divided  into 
three  groups  or  classifications,  namely,  water  jets  or  open  sprink- 
lers, shutters,  and  metal  or  metal-covered  frames  and  sash  in 
combination  with  glass. 

If  open  sprinklers  are  used  as  window  protection,  the  installa- 
tion should  be  made  by  some  sprinkler  company  which  is  satis- 
factory to  the  Underwriters  having  jurisdiction;  if  shutters  or 
fire-resisting  windows  are  used,  they  should  preferably  be  made 
and  installed  by  some  manufacturer  employing  the  label  service 
of  the  Underwriters'  Laboratories,  Inc.  Approved  fittings  and 
hardware  are  also  essential. 

Open  Sprinklers,  or  " water  curtains"  as  they  are  sometimes 
called,  are  described  in  detail  under  heading  "Open  Sprinklers" 
in  Chapter  XXX. 

Although  comparatively  few  experiences  have  adequately 
tested  the  efficiency  of  this  system  (for  several  actual  tests  see 
Chapter  XXX),  it  is  still  often  advocated  as  a  practical  means 


426        FIRE    PREVENTION    AND    FIRE    PROTECTION 

of  preventing  the  passage  of  flames  through  window  openings, 
even  to  the  exclusion  of  fire  shutters.  Such  dependence  upon 
open  sprinklers  is  not  justified  under  severe  conditions,  as  water 
is  diathermous,  like  wire  glass,  permitting  radiant  heat  to  pass 
through  readily.  Under  near  or  severe  exposure,  combustible 
contents  or  trim  inside  of  windows  protected  only  by  water 
curtains  .would  probably  be  set  on  fire  by  the  radiant  heat  pass- 
ing through  the  water,  about  as  quickly  as  though  no  sprinklers 
existed. 

The  report  by  Messrs.  E.  U.  Crosby,  C.  A.  Hexamer  and 
F.  J.  T.  Stewart  to  the  New  York  Board  of  Fire  Underwriters 
on  the  question  of  outside  sprinkler  protections  for  buildings  in 
New  York  City  summarizes  their  limitations  in  the  following 
conclusion: 

We  are  confident  that  open  sprinkler  systems  fed  by  high- 
pressure  fire  service  mains  cannot  be  relied  upon  as  a  conflagra-. 
tion  barrier  and  should  not  be  introduced  to  the  exclusion  of 
the  more  positive  protection  to  be  afforded  by  standard  wire 
glass  windows  and  shutters,  which  latter,  we  believe,  should  be 
required  at  all  street  fronts  in  exposure  districts. 

The  true  value  of  open  sprinklers  lies,  therefore,  in  their  use 
under  moderate  conditions,  especially  where  more  efficient  means 
may  be  either  impracticable  or  too  costly,  and  in  the  reinforce- 
ment which  they  may  provide,  under  severe  conditions,  to  some 
other  form  of  window  protection,  as,  for  instance,  in  augment- 
ing the  fire-resistance  of  shutters  or  wire  glass  windows.  Pro- 
tection to  wall  construction  which  is  not  fire-resistive  may  also 
be  valuable.  The  writer  recently  witnessed  a  severe  exposure 
fire  where  a  factory  building  with  exterior  walls  of  asbestos  pro- 
tected metal  would  soon  have  succumbed,  had  it  not  been  for 
the  efficient  work  done  by  the  cornice  sprinklers. 

FIRE-RESISTING  SHUTTERS. 

Types  of  Fire-resisting  Shutters. —  Ordinary  types  of  shut- 
ters comprise  what  are  usually  called  "  Standard"  or  "  Under  writ- 
ers'" shutters  of  wood,  covered  with  lock- jointed  sheet  tin,  — 
hinged  shutters  made  of  sheet-  or  corrugated-iron  in  various  forms, 
—  and  rolling  shutters  made  of  corrugated-  or  interlocking-metal, 
arranged  to  slide  up  and  down  like  a  curtain. 

These  types  are  usually  employed  outside  of  ordinary  wood  and 
glass  window  trim,  but  inside  hinged  or  rolling  shutters  may 


FIRE-RESISTING    WINDOWS,    SHUTTERS    AND    DOORS      427 

also  be  used,  where  those  of  the  rolling  type  are  made  to  coil  up 
in  especially  constructed  overhead  boxes,  or  where  those  of  the 
flat  hinged  type  are  folded  back  into  pockets  in  the  window 
jambs. 

In  spite  of  the  failure  of  all  of  these  types  of  shutters  under 
severe  test  conditions,  it  is  still  beyond  question  that  no  more 
effective  single  form  of  window  protection  can  be  devised  than 
an  approved  fire  shutter. 

Requisites  for  Fire  Shutters.  —  The  pros  and  cons  of 
various  types  of  shutters  are  considered  in  following  paragraphs, 
but  any  form,  to  be  acceptable,  should  combine  the  following 
requisites : 

(a)  Fire-resistance.  This  is  dependent  upon  the  material  of 
which  the  shutter  is  made,  and  upon  the  construction  and  method 
of  hanging. 

(6)  Ability  to  resist  the  radiation  of  heat. 

(c)  Capability  of  being  opened  from  the  outside. 

This  is  in  order  that  firemen  may  have  access  to  interior 
fire,  or  that  shutters  may  be  opened  to  permit  the  escape  of  those 
caught  in  the  interior  of  building.  The  National  Code  requires 
that  "all  shutters  opening  on  fire-escapes,  and  at  least  one  row, 
vertically,  in  every  three  vertical  rows  on  the  front  window 
openings  above  the  first  story  of  any  building,  shall  be  so  ar- 
ranged that  they  can  be  readily  opened  from  the  outside  by 
firemen." 

(d)  Ability  to  act  as  a  fire  shield  behind  which  firemen  may 
work.     For  this  purpose,  protected  hose  holes  should  be  provided 
on  at  least  one  shuttered  opening  per  room. 

Tin-covered  Shutters  are  usually  made  of  two  thicknesses 
of  tongued  and  grooved  if-inch  boards,  laid  at  right  angles  to 
each  other,  and  nailed  with  wrought-iron  nails,  which  are  driven 
flush  and  clinched  on  the  other  side.  This  woodwork  is  then 
covered  on 'both  sides  and  edge  with  sheets  of  tin,  lock-jointed 
together. 

The  National  Board  " Standard"  requirements  are  as  follows: 

(a)  To  be  hung  next  to  masonry,  either  over-lapping  win- 
dow opening  4  inches  or  fitting  close  inside  opening. 

(6)  Construction  to  be  the  same  as  for  fire  doors,  except 
that  only  two  thicknesses  of  ^f-inch  board  are  required,  layers 
of  boards  to  be  at  right  angles. 

(c)  When  made  in  pairs,  the  edges  coming  together  should 
be  slightly  beveled  (not  rabbetted)  to  allow  the  shutters  to  be 
readily  opened  and  closed,  and  to  aid  in  making  a  tight  fit. 


•— u 


428         FIRE   PREVENTION   AND   FIRE    PROTECTION 

Shutters  made  in  pairs  do  not  furnish  as  reliable  protec- 
tion as  single  shutters. 

Joints  between  shutters  may  be  protected  by  a  i  by  21- 
inch  iron  astragal  bolted  to  one  shutter  by  carriage  bolts  spaced 
10  inches  apart. 

(d)  Tin  covering  to  be  the  same  as  for  fire  doors,  except 
that  seams  should  be  made  with  the  upper  sheet  lapping  out- 
side of  under  one,  so  as  to  shed  water. 

Nails  for  attaching  covering  to  be  1}* inches  long,  otherwise 
to  comply  with  those  specified  for  fire  doors. 

(e)  Hinges   to   be   wrought    iron   --f$   inch    by    If    inches. 
Same  to   be  secured  by  bolts  passing   through   shutter  with 
washers  under  bolt  heads. 

(/)  Substantial  wrought-iron  pin  or  eye  blocks  to  be  securely 
set  in  wall  or  bolted  through  wall. 

(g)  Shutters  to  be  secured  shut  by  at  least  two  1|  by  f  in. 
steel  latches,  working  together  and  spaced  about  J  the  distance 
from  top  and  bottom  of  the  window  opening.  Latches  to  pivot 
on  | -inch  bolts  through  the  shutter.  Catches  to  be  provided 
with  a  flare  and  fastened  to  the  shutter  by  two  through  bolts. 

(h)  At  least  one  shutter  in  three  on  each  floor  above  the 
first  and  below  the  seventh,  and  shutters  next  to  fire  escapes  and 
above  adjoining  buildings  to  be  constructed  so  that  they  can  be 
operated  from  both  inside  and  outside. 

(i)  The  use  of  expansion  bolts  in  mounting  shutters  is  not 
approved. 

(j[)  When  sliding  shutters  are  used  outside  (should  not  be 
if  avoidable),  metal  shields  should  be  provided  to  prevent  accu- 
mulation of  snow  or  ice  on  the  track. 

Sliding  fire  shutters  not  to  be  installed  except  subject  to 
underwriters  having  jurisdiction. 

Painting.  —  A  light-colored  paint  is  recommended  for  fire 
shutters,  but  first  give  them  a  coat  of  metallic  brown,  Venetian 
red,  or  red-oxide  paint,  ground  in  pure  linseed  oil. 

Care  and  Maintenance.  —  (a)  Fire  shutters  should  be 
ready  for  instant  use  at  all  times,  therefore  it  is  necessary  to 
keep  the  surroundings  clear  of  everything  that  would  be  likely 
to  obstruct  or  interfere  with  their  free  operation.  They  should 
be  kept  closed  and  fastened  nights,  Sundays  and  holidays,  and 
whenever  the  openings  are  not  in  use. 

(6)  Never  tack  any  tin  on  a  tin-clad  shutter.  When  tin 
becomes  worn,  substitute  new  sheets  in  the  same  manner  as 
when  covering  a  new  shutter. 

The  fact  should  be  emphasized,  that  a  novice,  carpenter, 
tinsmith  or  metal  worker,  unless  trained  and  experienced  in 
their  manufacture,  cannot  be  relied  upon  to  make  standard 
doors  and  shutters.  In  order  to  obtain  such,  property  owners 
should  contract  with  those  making  this  work  a  specialty,  and 
who  are  recommended  by  the  underwriters  as  turning  out  an 
honest  and  reliable  article.  It  is  also  important  that  they 


FIRE-RESISTING    WINDOWS,    SHUTTERS   AND    DOORS      429 

should  be  employed  to  attach  the  fittings  and  hang  the  doors 
and  shutters  in  place.  The  efficiency  of  a  good  device  has  often 
been  practically  destroyed  by  its  being  improperly  hung.  The 
strict  observation  of  these  suggestions  will  mean  an  actual 
saving  of  money,  as  well  as  greater  protection.* 

Efficiency  of  Tin-covered  Shutters.  —  It  is  probable  that  stand- 
ard tin-covered  shutters  will  be  found  about  as  effective  un- 
der severe  test  as  any  single  form  of  present-day  window  pro- 
tection. Many  fires  have  demonstrated  their  efficiency  under 
severe  conditions,  but  that  they  are  all  that  could  be  desired 
under  conflagration  conditions  cannot  be  maintained  after  their 
record  in  the  Baltimore  and  San  Francisco  fires. 

The  report  of  the  National  Fire  Protection  Association  on  the 
Baltimore  fire  stated  that 

The  fact  that  many  non-standard  fire  shutters  failed  in 
this  conflagration  should  not  cause  a  loss  of  faith  in  the  standard 
shutter  as  specified  by  the  National  Board  of  Fire  Underwriters. 
The  shutters  in  the  buildings  mentioned  in  this  report  were 
generally  latched  to  the  wooden  window  frames  back  of  them, 
and  were  exposed  to  continued  heat  on  both  sides.  Standard 
fire  shutters  properly  mounted  and  fully  applied  will  furnish 
reliable  protection  against  exposure  fires  as  severe  as  that  of  the 
Baltimore  conflagration. 

This  opinion  is  decidedly  optimistic,  in  that  the  general  failure 
of  tin-covered  shutters  in  Baltimore  is  largely  attributed  to 
improper  hanging,  and  to  exposure  on  both  sides.  The  former 
fault  is  easily  rectified,  but  the  latter  condition  cannot  be  dis- 
regarded until  fire-resistive  construction  is  far  more  general  than 
is  indicated  by  any  present  prospects.  The  great  weakness  of 
a  tin-clad  shutter  lies  in  the  burning  out  of  its  wood  core,  thus 
destroying  its  strength  and  rigidity,  and  in  the  bursting  of  the 
tin  covering  under  the  action  of  the  gases  generated  by  the 
combustion  of  the  wood. 

One  of  the  great  lessons  that  I  brought  away  from  the 
Baltimore  fire  was  that  our  standard  tin  covering  for  the  under- 
writer's shutter  is  all  right,  and  that  this  covering  material  has 
sufficient  power  of  resistance  to  withstand  the  fiercest  heat  of  a 
great  conflagration,  but  that  we  do  need  to  find  some  better 
material  than  pine  wood  to  fill  it  with.  .  .  .  The  standard 
underwriter's  shutter  of  wood  covered  with  tin  did  not  give  a 
very  good  account  of  itself  in  the  Baltimore  fire,  and  I  think  it 
can  be  said,  without  fear  of  serious  contradiction,  that  the  en- 

*  Crosby  and  Fiske's  "Handbook  of  Fire  Protection  for  Improved  Risks." 


430         FIRE    PREVENTION    AND    FIRE    PROTECTION 

durance  of  the  ordinary  underwriter's  shutter  of  tin-dad  wood 
is  limited  to  not  more  than  about  half  an  hour's  endurance  of  a 
temperature  of  1500  degrees,  and  that  this  limit  is  often  passed 
in  the  heat  of  an  ordinary  conflagration.  .  .  .  Although  the 
present  shutter  and  the  present  approved  form  of  fire  door  are 
all  right  nine-tenths  of  the  time,  and  perhaps  nineteen-twenti- 
eths  of  the  time,  they  are  not  all  that  we  need  in  a  great  con- 
flagration.* 

A  great  many  non-standard  tin-covered  shutters  were  used  in 
San  Francisco,  "and  anybody  who  visited  that  city  shortly 
after  the  catastrophe  and  saw  the  number  of  walls  with  shutters 
hanging  up  in  place  with  the  sheets  of  tin  fluttering  like  leaves 
on  a  tree,  must  have  been  impressed  with  the  fact  that  they 
were  not  of  much  value. "f  A  typical  example  of  the  failure  of 
tin-covered  shutters  in  the  San  Francisco  conflagration  is  shown 
in  Fig.  115. 

The  test  of  a  tin-covered  door  made  by  the  British  Fire  Pre- 
vention Committee  is  described  under  later  paragraph  "  Tin- 
covered  Doors." 

Advantages  and  Disadvantages  of.  —  Advantages  include  cheap- 
ness, — general  availability  according  to  standard  requirements — 
and  usual  efficiency  because  both  good  workmanship  and  proper 
application  are  now  well  understood. 

Disadvantages  include  deterioration  under  action  of  weather, 
and  the  rotting  of  the  concealed  wood  core,  —  cost  and  uncer- 
tainty of  proper  maintenance  owing  to  such  deterioration,  — 
and  appearance.  See  also  " Shutters  vs.  Wire  Glass  Windows/' 

Sheet-iron  Shutters  were  one  of  the  earliest  types  of  sup- 
posedly efficient  window  protections.  While  still  employed  to 
a  limited  extent,  and  recognized  by  the  National  Board  of  Fire 
Underwriters  in  their  standard  requirements  for  fire  shutters,  it 
will  be  found  that  a  great  majority  of  those  at  present  in  service 
were  installed  at  some  date  when  incombustibility  and  fire- 
resistance  were  supposed  to  be  synonymous  —  in  other  words, 
before  anything  very  much  better  was  known. 

The  principal  standard  requirements  as  to  construction  are 
as  follows: 

(a)  To  be  made  of  No.  14  gauge  sheet-iron  or  steel  and  so 
as  to  lap  the  wall  at  least  1J  inches  all  around.  The  bottom  of 
the  shutter  to  fit  the  sill  closely  if  it  is  not  practical  to  lap  it. 

*  From  address  of  Mr.  John  R.  Freeman  at  the  annual  banquet  of  the 
National  Board  of  Fire  Underwriters,  May,  1904. 

t  1911  Proceedings  National  Fire  Protection  Association,  page  56. 


FIRE-RESISTING    WINDOWS,    SHUTTERS    AND    DOORS      431 


FIG.   115,  —  Tin-covered  Shutters  in  San  Francisco  Conflagration. 


432         FIRE    PREVENTION    AND    FIRE    PROTECTION 


FIG.   116.  —  Plate-iron  Shutters  in  San  Francisco  Conflagration. 


FIG.   117.  —  Plate-iron  Shutters  in  San  Francisco  Conflagration. 


FIRE-RESISTING   WINDOWS,    SHUTTERS   AND   DOORS      433 

(6)  Frames  to  be  of  1^-  by  j-inch  angle  iron  with  not  less 
than  two  cross  bars  of  the  same  material.  Shutters  over  six 
feet  in  height  to  have  cross  bars  not  exceeding  two  feet  apart. 
Frame  to  enter  wall  opening  when  shutter  is  closed. 

Continuous  welded  frames  and  cross  bars  of  1J-  by  J-inch 
iron  are  often  used,  but  are  not  considered  the  full  equivalent 
of  the  angle-iron  frame.  The  welded  frame  is  often  necessary 
when  folding  shutters  are  used. 


FIG.    118.  —  "Saino"  Corrugated-iron  Fire  Shutter. 

Efficiency:  Fire  Tests.  —  While  sheet-iron  shutters  have  per- 
formed good  service  in  many  fires  under  moderate  test,  they  are 
not  dependable  under  conditions  at  all  severe.  The  test  of  a 
sheet-iron  door  (practically  the  equivalent  of  a  sheet-iron  shutter) 
made  by  the  British  Fire  Prevention  Committee,  is  described 


434         FIRE    PREVENTION    AND    FIRE    PROTECTION 

under  later  paragraph  " Sheet-iron  Doors,"  while  the  warping  of 
such  shutters  under  conflagration  conditions  is  illustrated  in 
Figs.  116  and  117  which  show  the  alley  elevations  of  two  build- 
ings after  the  San  Francisco  fire.  See  also  "  Inside  Folding 
Shutters." 

Advantages  and  Disadvantages  of.  —  Advantages  include  en- 
durance under  wear  and  tear  and  exposure  to  weather,  and  im- 
proved appearance  over  tin-covered  shutters. 

Disadvantages  include  difficulty  of  obtaining  standard  con- 
struction and  hanging,  expansion  and  warping  under  severe  heat, 
radiation  of  heat,  excessive  weight,  thus  making  closing  more 
difficult  and  hence  less  likely,  and  increased  cost  over  tin-covered 
shutters. 

Corrugated-iron  Shutters.  —  Very  efficient  corrugated- 
iron  shutters  made  by  the  Saino  Fire  Door  and  Shutter  Com- 
pany, Memphis,  Tennessee,  are  largely  used  locally  and  are 
highly  spoken  of  by  officers  of  the  Memphis  Fire  Department. 
They  are  made  of  No.  22  gauge  corrugated  galvanized  steel, 
the  2J-inch  corrugations  of  the  outer  plates  running  horizontally 
(thus  giving  the  appearance  of  any  ordinary  wood  slatted  blind), 
while  the  corrugations  of  the  inner  sheets  are  vertical.  A  sheet 
of  12-pound  asbestos  is  placed  between.  The  general  appear- 
ance of  these  shutters  is  illustrated  in  Fig.  118,  while  the  stiffen- 
ing rib  which  is  placed  along  all  of  the  long  edges  of  the  shutters 
is  shown  at  one-fourth  size  in  Fig.  119.  The  pin  shown  pro- 
Vertical  Sheet  #  22  Galv.  Corrug-. 


Stiffening. 


Rib  \_J Horizontal  Sheet  #  22  Galv.  Corrug-. 


HORIZONTAL  SECTION  AT  SIDE   EDGE 
FIG.    119.  —  Detail  of  "Saino"  Fire  Shutter. 

jecting  through  the  shutter  in  Fig.  118  is  attached  to  the  inside 
latch,  so  that  the  shutters  may  be  opened  from  the  outside  by  a 
fireman's  pike  pole. 

Inside  Iron  Folding  Shutters,  like  outside  sheet-iron  shut- 
ters, are  now  seldom  used.  They  were  frequently  installed  in 
the  earlier  types  of  so-called  fireproof  buildings,  but  they  possess 
the  same  disadvantages  as  the  outside  shutters,  with  the  further 
objection  that  merchandise  is  liable  to  be  so  placed  as  to  prevent 
their  closing.  When  made  to  fold  back  into  pockets  or  recesses 
in  the  window  jambs,  this  objection  may  be  overcome  (except 


FIRE-RESISTING    WINDOWS,    SHUTTERS    AND    DOORS       435 

in  storage  buildings  and  the  like),  but  such  arrangement  requires 
thicker  walls  than  are  now  usual.  The  proper  de'sign  and  hang- 
ing vitally  affect  the  efficiency. 

Efficiency  of  Inside  Shutters.  —  In  the  Baltimore  fire  the  one- 
story  Safe  Deposit  and  Trust  Company's  Building  had  its  win- 
dows protected  by  cast-iron  frames  and  by  inside  folding  shutters 
made  of  j-inch  plate  with  1-inch  by  J-inch  flat  battens  around 
the  edges.  In  spite  of  a  severe  exposure  on  one  side,  owing  to 
the  burning  of  the  "Sun"  Building  across  a  ten-foot  alley,  these 
shutters  formed  efficient  protection.  This  was  made  possible 
through  the  fact  that  no  combustible  material  was  near  them  on 
the  inside  of  building. 

In  commenting  on  this,  Mr.  Freeman  considers  that  the  favor- 
able result  was  due  to  the  fact  that  the  shutters  were  free  from 
ribs  (which  are  required  in  the  National  Board  rules),  and  that 
they  were  so  set  in  iron  frames  as  to  permit  free  expansion  with- 
out opening  up  cracks. 

The  record  of  inside  folding  shutters  in  the  San  Francisco 
conflagration  has  been  previously  mentioned  (see  report  of  Mr.  S. 
Albert  Reed,  page  424).  The  United  States  Mint,  however, 
which  Mr.  Reed  mentions  as  an  example  showing  the  efficiency 
of  inside  folding  shutters,  was  principally  saved  through  the 
efforts  of  employees  in  using  fire  hose  and  pumps,  connected  to 
an  artesian  well. 

Great  improvement  is  possible  along  the  line  of  efficient  inside 
folding  shutter  protection. 

Steel  Rolling  Fire  Shutters  are  placed  either  on  the  outside 
of  window  openings,  or  in  the  window  reveals  immediately  in 
front  of  the  window  frames  and  sash.  The  operation  of  such 
shutters  may  be  manual,  chain-hoist,  automatic,  or  a  combina- 
tion of  these  operations. 

Rolling-  Shutters  in  Wall  Reveals  may  be  arranged  as  shown  in 
Fig.  120.  The  operating  hand  chain  hangs  down  at  one  jamb 
between  the  inside  of  shutter  and  the  window.  Thus  no  operat- 
ing parts  are  inside  the  building. 

If  desired,  the  window  head  may  be  arranged  to  conceal  the 
coil,  as  shown  in  Fig.  121.  Medium-sized  shutters  may  be 
operated  manually,  or  shutters  for  large  openings  may  be  ar- 
ranged with  a  chain  hoist,  in  which  case  the  chain  and  sprocket 
wheel  are  placed  on  the  trim  at  one  side  of  the  opening,  being 
connected  to  the  shutter  coil  by  means  of  bevel  gearing  in  the 


436 


FIRE    PREVENTION   AND    FIRE    PROTECTION 


head  space.     In  such  constructions  the  head  casing  or  panel 
must  be  removable  to  permit  access  to  the  coil. 


FIG.   120.  —  Steel  Rolling  Shutter  in 
Wall  Reveal. 


FIG.   121.  — Steel     Rolling     Shutter 
with  Concealed  Coil. 


Outside  rolling  shutters  may  be  arranged  to  operate  manually, 
in  which  case  the  opening  and  closing  is  effected  through  the  use 
of  a  removable  crank  applied  on  the  inside  of  wall,  —  or  by  means 
of  a  chain  hoist,  in  which  case  an  inside  chain  hoist,  similar  to 
that  shown  in  Fig.  121,  is  connected  with  a  bevel  gear  and  a  rod 
running  through  the  wall,  at  one  end  of  the  top  coil,  —  or  they 
may  operate  automatically. 

Automatic  rolling  shutters  are  the  only  type  of  steel  rolling 
shutters  approved  by  the  Underwriters'  Laboratories,  Inc.  for 
use  in  window  openings.  The  "  Abacus  No.  4,"  manufactured 
by  the  Kinnear  Manufacturing  Company,  is  approved  for 


FIRE-RESISTING   WINDOWS,    SHUTTERS   AND   DOORS      437 

window  use  in  openings  not  exceeding  10  feet  wide  by  10  feet 
high. 

This  shutter  is  normally  open,  closure  being  effected  by  means 
of  an  automatic  release  which  is  actuated  by  a  fusible  link.  The 
releasing  device  admits  of  testing  without  fusing  the  link,  and 
the  shutter  may  then  be  recoiled  manually  by  means  of  a  handle 
at  the  bottom  of  shutter. 

The  appearance  when  normally  open  is  shown  in  Fig.  122, 


FIG.   122.  —  "Abacus  No.  4"  Steel  Window  Shutter. 

while  an  installation  of  such  shutters  in  the  light  court  of  the 
Corn  Exchange  Bank  Building,  Chicago,  is  shown  in  Fig.  123. 
The  shutter  is  made  to  overlap  the  window  opening  at  sides 
and  top,  traveling  in  side  grooves  which  are  applied  to  the  face 


— jj 


438         FIRE    PREVENTION   AND    FIRE    PROTECTION 

of  wall.     The  curtain  is  composed  of  interlocking  slats  made  of 
No.  22  IT.  S.  gauge  galvanized  steel.     The  coil  is  protected  by 


FIG.   123.  —  Light  Court  of  Corn  Exchange  Bank  Building,  Chicago. 

a  galvanized  steel  hood,  and  the  automatic  release  by  a  cast- 
iron  housing  placed  at  end  of  hood. 

In  the  United  States  Appraisers'  Warehouse  in  New  York  City 
the  windows  of  one  important  story  are  provided  with  rolling 


FIRE-RESISTING    WINDOWS,    SHUTTERS    AND    DOORS      439 

steel  shutters  so  arranged  as  to  be  operated  simultaneously  by 
electric  connection. 

Efficiency  of  Steel  Rolling  Shutters.  —  Tests  made  by  the  British 
Fire  Prevention  Committee  on  steel  rolling  doors,  described  later 


FIG.  124.  —  Pacific  States  Tel.  &  Tel.  Co.'s  Building,  San  Francisco 
Conflagration. 

in  this  chapter,  show  conclusively  that  such  constructions  possess 
a  very  high  degree  of  fire-resistance,  and  also  that  the  radiation 
of  heat  through  the  curtains  is  not  as  great  as  would  naturally 
be  expected.  Also,  the  numerous  tests  of  steel  rolling  shutters 
and  doors  afforded  by  the  San  Francisco  fire  constitute  a  decided 


440         FIRE    PREVENTION    AND    FIRE    PROTECTION 

recommendation  for  this  means  of  protecting  window  and  door 
openings. 

The  case  of  the  Pacific  States  Telephone  and  Telegraph  Com- 
pany's Building  has  been  previously  mentioned  (see  report  of 
Mr.  S.  Albert  Reed,  page  424).  This  building,  shown  in  Fig.  124, 
had  all  openings  on  the  front  elevation  fitted  with  wood  and 
plate  glass  windows,  protected  by  Kinnear  rolling  shutters.  All 
other  openings  in  the  building,  save  one,  were  protected  by  wire 
glass  windows  and  sliding  tin-covered  shutters.  Had  not  one 


*IG.  125.  —  Second  Floor  Interior  of  Pacific  States  Tel.  &  Tel.  Co.'s  Building 
after  San  Francisco  Conflagration. 

opening  been  unprotected,  —  viz.,  a  large  rear  door  at  the  south- 
west corner,  —  it  is  probable  that  this  building  would  have  es- 
caped without  damage.  As  it  was,  almost  the  entire  damage 
resulted  from  the  interior  fire  which  was  so  severe,  due  to  the 
burning  of  insulated  wire  and  other  supplies,  as  to  melt  glass 
and  weld  nails.  In  spite  of  this,  the  rolling  shutters  were  not 
materially  damaged,  and  were  re-used  with  the  exception  of 
one  shutter.  They  were  intended  to  protect  the  exterior  against 
exposure  fire,  but  incidentally  they  amply  proved  their  efficiency 
and  value  by  protecting  the  fagade  from  the  fire  within.  The 
experience  in  the  Baltimore  buildings  showed  how  serious  this 


FIRE-RESISTING    WINDOWS,    SHUTTERS   AND   DOORS      441 

damage  might  have  been,  especially  around  window  openings. 
Fig.  125  shows  the  conditions  on  the  interior  of  the  second  floor. 
The  openings  at  the  bottoms  of  the  shutters  were  caused  by  the 
burning  out  of  the  wooden  window  sills. 

Advantages  and  Disadvantages.  —  Rolling  shutters,  whether 
open  or  closed,  form  the  least  objectionably  appearing  type  of 
shutter  protection  for  windows.  Indeed  they  have  been  adapted 
to  many  buildings  of  even  monumental  appearance,  such  as,  for 
instance,  the  Pacific  Mutual  Life  Building,  at  Los  Angeles,  Cal. 
For  the  better  class  of  buildings  the  writer  believes  that  their  use 
should  decidedly  be  encouraged,  as  the  preceding  instances  show 
that  they  are  entirely  adequate  for  all  ordinary  exposure  tests. 
For  severe  conditions,  open  sprinklers  placed  in  front  of  shutters 
in  wall  reveals  should  answer  all  requirements. 

Disadvantages  include  deterioration  under  exposure  to 
weather,  requiring  constant  maintenance  to  insure  absence 
from  rusting  and  consequent  inoperation,  —  the  fact  that  pro- 
tected hose  holes  are  not  possible,  but  that  the  shutter  must  be 
raised  to  be  used  by  firemen  when  working  behind  same,  —  and 
the  radiation  of  heat  under  very  near  or  very  severe  exposure. 

FIRE-RESISTING  WINDOWS 

Types  of.  —  If  the  exposure  is  not  severe  enough  to  require 
the  use  of  hinged  or  rolling  shutters,  or  if  the  appearance  of 
shutters  is  objected  to,  then  recourse  may  be  had  to  a  less  efficient 
construction,  but  one  of  more  pleasing  appearance,  namely,  metal 
or  metal-covered  frames  in  combination  with  wire,  prism  or  elec- 
tro-glazed glass.  The  more  ordinary  types  of  this  nature  may 
be  divided  into  hollow  sheet-metal,  kalamine,  cast-  or  wrought- 
iron,  and  drawn-  or  cast-bronze.  In  all  of  these  constructions, 
if  used  without  additional  outside  or  inside  shutters,  it  must  be 
remembered  that  the  glass  employed  within  the  sash,  whether 
plate,  wire,  prism  or  electro-glazed,  will  still  permit  the  passage 
of  radiated  heat  through  the  openings.  Hence,  if  there  are  no 
means  of  coping  with  numerous  window  fires,  or,  if  the  exposure 
is  very  near  or  very  severe,  these  types  are  not  to  be  recom- 
mended, unless  used  in  combination  with  shutters,  or  outside 
sprinklers,  or  both. 

Prospective  users  should  first  ascertain  from  the  underwriters 
having  jurisdiction  which  type,  if  any,  of  wire  glass  windows 


442 


FIRE    PREVENTION    AND    FIRE    PROTECTION 


will  be  accepted  in  the  location  desired,  and  should  make  con- 
tracts subject  to  approval  by  them  of  the  installation,  glazing, 
and  automatic  attachments. 

Hollow  Sheet-Metal  Windows.  —  Hollow  sheet-metal  win- 
dow frames  and  sash  in  combination  with  wire  glass  comprise  by 
far  the  greatest  percentage  of  fire-resisting  windows  now  in  use. 
They  also  constitute  one  of  the  best  types  of  moderate  cost  in 
common  practice,  as  great  improvements  have  been  made  during 
recent  years,  both  in  design  and  in  manufacture,  owing  partly 
to  the  recommendations  and  standardization  of  the  National 
Fire  Protection  Association,  and  partly  to  the  tests  and  labeling 
system  of  the  Underwriters'  Laboratories.  The  extent  of  their 

use  is  indicated  by  the  fact 
that  67  manufacturers,  covering 
22  distinct  types  of  windows, 
have  each  had  from  one  to  18 
types  approved  by  the  Labora- 
tories. 

Hollow-metal  windows  are 
made  of  galvanized-iron  or  cop- 
per, or  sometimes  of  copper  or 
bronze-plated  sheet  metal.  The 
lights  are  of  wire  glass,  either 
plate  or  maze  where  light  and 
appearance  are  essential  con- 
siderations, or  rough  or  ribbed 
wire  glass  where  it  is  desired  to 
secure  light  without  the  distrac- 
tion to  the  operatives  of  facto- 
ries, etc.,  from  outside  sights. 
The  details  of  construction  of 
such  frames  and  sash,  and  the 
maximum  permissible  sizes  of 


glass  openings,  are  all  fixed 
within  certain  limits  by  the 
rules  and  regulations  of  the 
National  Board  of  Fire  Under- 
writers, which  may  be  obtained  on  request.  The  principal 


FIG.  126.  —  Double-hung  Hollow 
Sheet-metal  Windows. 


regulations  are  as  follows: 

Maximum  Size  of  Frame.  —  Metal   frame   containing  the 
sash  or  glass  not  to  exceed  5  feet  by  9  feet  between  supports, 


FIRE-RESISTING    WINDOWS,    SHUTTERS   AND   DOORS      443 

The  above  size  is  designed  to  take  the  maximum  glass 
sizes  with  allowance  for  the  metal  parts  and  is  as  large  as  can 
safely  be  permitted. 

Size  of  Glass.  —  (a)  The  unsupported  surface  of  the  glass 
allowed  shall  be  governed  by  the  severity  of  exposure  and  be 
determined  in  each  case  by  the  Underwriters  having  jurisdic- 
tion, but  in  no  case  shall  it  be  more  than  48  inches  in  either 
dimension  or  exceed  720  square  inches. 

(6)  The  glass  to  be  of  such  dimensions,  after  selvage  is 
removed,  that  the  bearing  in  the  groove  or  rabbet  is  not  less 
than  f-inch. 

Material.  —  (a)  To  be  of  at  least  No.  24  gauge  galvanized- 
iron  and  of  a  quality  soft  enough  to  permit  all  necessary  bending 
without  breakage.  The  galvanizing  not  to  flake  or  break  badly 
in  bending. 

This  applies  to  all  parts  of  the  frame  and  sash. 

Experience  has  demonstrated  that  a  metal  too  light  to 
insure  a  substantial  and  durable  frame  is  liable  to  be  used,  par- 
ticularly in  the  larger  frames. 

(b)  To  be  of  20-ounce  copper  or  heavier  where  copper 
frames  or  sash  are  used. 

The  copper  frame  is  not  considered  the  full  equivalent  of 
the  iron  frame  as  a  fire-retardant  on  account  of  the  compara- 
tively low  fusing  point  of  copper.  In  localities  subject  to 
unusually  corrosive  atmospheric  influences  and  where  galvanized- 
iron  will  rust  out  rapidly,  the  copper  frame  may  be  recommended 
providing  the  exposure  is  not  extreme.  The  copper  frame 
should  not  be  used  in  elevator  shafts,  ventilators,  partitions  or 
where  liable  to  be  subjected  to  intense  internal  fires. 

Various  types  of  hollow-metal  windows  include  sash  arranged 
as  follows: 

Stationary. — -Hinged  upper,  stationary  lower.     Also  with  sta- 
tionary, pivoted  or  hinged  transom. 

Casement.  —  Double  hung.     Also  with  stationary,   hinged  or 
pivoted  transom. 

Pivoted;  — •  Single  sash,  top  and  bottom  pivots. 
Upper  and  lower  sashes  pivoted. 
Upper  sash  side  pivoted,  lower  sash  stationary. 
Lower  sash  side  pivoted,  upper  sash  stationary. 
Pivoted  middle  sash,  upper  and  lower  stationary. 
Upper,  middle  and  lower  sashes  pivoted. 
Pivoted  upper,  two  lower  stationary. 
Pivoted  upper  and  lower,  middle  stationary. 
Combination.  —  Pivoted  upper  sash,  double  hung  lower  sash. 
"  Twin ' '  or  Double  Windows.  —  See  later  paragraph  "  Double- 
glazed  Sash." 

A  double-hung  sheet-metal  window,  made  by  S.  H.  Pomeroy 
Company,  Inc.,  is  illustrated  in  Fig.  126, 


444 


FIRE    PREVENTION   AND    FIRE    PROTECTION 


The  principal  disadvantage  pertaining  to  sheet-metal  windows 
is  their  rapid  deterioration  under  neglect. 

Kalamine  Windows.  —  Kalamine  window  frames  and  sash, 
or  sheet  metal  over  wood  cores,  are  principally  used  for  light 
exposures  where  the  danger  from  flying  sparks  is  intended  to 
be  guarded  against,  rather  than  where  any  direct  exposure  is  to 
be  met.  They  are  non-combustible  rather  than  fire-resisting. 


FIG.   126A.  —  Section  and  Plan  of  Kalamine  Window. 

The  lights  are  usually  of  plate  glass,  especially  if  kalamine  trim 
is  used  simply  to  cover  the  law  in  those  cities  where  non-com- 
bustible windows  and  doors,  etc.,  are  required  in  buildings  of  a 
certain  class  or  of  a  height  above  fixed  limits.  Previous  mention 
has  been  made  of  their  efficiency  as  demonstrated  in  the  burning 
of  the  Kohl  Building  in  San  Francisco,  and  their  value,  even  as 
a  sub-standard  protection,  has  been  pointed  out;  but  for  efficient 
fire-resistance,  kalamine  windows,  especially,  are  an  unknown 


FIRE-RESISTING    WINDOWS,    SHUTTERS   AND   DOORS      445 

quantity,  as  the  resistance  offered  by  the  lighter  members,  such 
as  sash  rails,  is  questionable. 

Such  frames  and  sash  are  made  of  steel,  galvanized-iron  or 
copper,  and  the  better  examples  of  the  work  present  pleasing 
workmanship  and  finish.  If  some  composition  could  be  used 
for  the  body  instead  of  wood,  without  producing  chemical  action 
harmful  to  the  metal,  a  superior  type  of  kalamine  work  would 
result  which  would  be  of  great  value. 

Fig.  126A  illustrates  section  and  plan  of  a  kalamine  window  as 
made  by  the  Thorp  Fireproof  Door  Company,  Minneapolis, 
Minn. 

Wrought-  and  Cast-iron  Windows.  —  Wrought-iron  frames 
can  be  used  to  advantage  in  localities  subject  to  severe  exposure 
or  to  unusually  corrosive  atmospheric  conditions,  although  their 
use  is  not  limited  to  such  locations.  The  pivoted  sash  and 
stationary  window  seem  to  be  best  adapted  for  use  with  such 
frames,  but  the  specifications  may  be  applied  to  other  forms  in 
all  essential  points. 

Size  of  Glass.  —  (a)  The  unsupported  surface  of  the  glass 
illowed  shall  be  governed  by  the  severity  of  exposure  and  be 
determined  in  each  case  by  the  Underwriters  having  jurisdic- 
tion, but  in  no  case  shall  it  be  more  than  48  inches  in  either 
dimension  or  exceed  720  square  inches. 

(6)  The  glass  to  be  of  such  dimensions,  after  selvage  is 
removed,  that  the  bearing  in  the  groove  or  rabbet  is  not  less 
than  f  inch. 

(c)  The  glass  to  be  retained  by  the  structural  part  of  the 
frame  or  sash  independently  of  the  material  which  may  be 
used  for  weatherproof  purposes.  Only  non-inflammable  mate- 
rial to  be  used  in  setting  glass  in  the  sash. 

Frames.  —  (a)  To  be  made  of  3^-  by  f-inch  flat  iron, 
welded  so  as  to  be  continuous,  or  fastened  at  the  corners  with 
suitable  angles  securely  riveted  on  outside  of  the  frame. 

(6)  To  be  set  next  to  the  masonry  and  anchored  to  the 
wall  by  2-  by  |-inch  anchor  irons  securely  riveted  to  the  frame 
and  bent  so  as  to  enter  the  wall. 

Sash.  —  To  be  made  of  1^-  by  1^-  by  J-mch  angle  iron. 
The  rails  and  stiles  to  be  welded  together  at  the  corners  so  as  to 
be  continuous. 

Muntins.  —  To  be  of  If-  by  1^-  by  |-inch  tee  iron  welded 
to  each  other  at  each  intersection  and  also  to  the  stiles  and  rails 
so  as  to  form  proper  rabbets  for  the  glass. 

Stops.  —  Inside  angles  holding  the  glass  in  the  frame  to 
be  of  1-  by  1-  by  |-inch  angle  iron  fastened  with  bolts  so  that  they 
can  be  removed  for  reglazing. 


446 


FIRE    PREVENTION   AND    FIRE    PROTECTION 


Casement  windows  made  of  especially  rolled  wrought-iron 
sections,  as  illustrated  in  Chapter  XXIV,  are  quite  frequently 
used  in  England  and  in  European  practice,  but  have  never  been 
introduced  to  any  great  extent  in  this  country  except  in  resi- 


FIG.  127.  —  Cast-iron  Entrance  Screen,  Pennsylvania  Railroad  Station,  N.  Y. 

dences.  The  nearest  comparable  type  is  the  window  made  of 
rolled  steel  sections,  with  pivoted  sash,  usually  limited  to  factory 
buildings,  etc.,  as  described  under  the  "Fenestra"  and  " United 
Steel"  systems,  etc.,  in  Chapter  XXV. 


FIRE-RESISTING   WINDOWS,    SHUTTERS   AND   DOORS      447 

Cast-iron  frames  and  sash,  when  used  in  combination  with  wire 
glass,  will  insure  a  construction  as  thoroughly  fire-resisting  as 
can  probably  be  devised  with  the  use  of  glass.  An  extensive 


FIG.    12S.  —  Drawn-bronze  Window,  Boston  Art  Museum. 

field  for  cast-iron  window  construction  has  been  developed  in 
the  modern  design  of  power  houses,  etc.,  where  large  and  high 
window  areas  are  needed  for  light  and  ventilation.  In  such 
cases,  groups  of  sash  are  connected  by  a  system  of  vertical  and 


448         FIRE   PREVENTION  ,AND   FIRE   PROTECTION 

horizontal  operating  rods  which  may  easily  be  controlled  from 
the  floor  level.  A  typical  arrangement  of  this  character,  but 
without  wire  glass,  is  illustrated  in  Fig.  127  which  shows  an 
entrance  screen  at  the  new  Pennsylvania  Railroad  station,  New 
York. 


FIG.  129.  —  Drawn-bronze  Sash,  Grand  Central  Station  Building,  N.  Y. 

Drawn-bronze  Windows.  —  For  vast  or  imposing  fire-re- 
sisting buildings,  where  appearance  is  an  essential  consideration, 
nothing  better  can  be  used  (either  from  the  standpoint  of  finish 
or  efficiency)  than  drawn-bronze  sections  for  window  frames  and 
sash.  Such  open  or  closed  sections  as  the  architect  may  desire 
for  frames  or  sash  (but  without  ornamentation)  are  " drawn"  out 


FIRE-RESISTING    WINDOWS,    SHUTTERS   AND    DOORS      449 


of  sheet  brass  or  bronze  by  pulling,  on  a  "draw  bench,"  the  plates 
of  the  required  perimeter  through  especially  made  dies  of  the 
necessary  shapes.  Closed  sections,  such  as  the  sash  members, 
are  made  seamless  by  brazing  the  joints  before  " drawing." 
Fig.  128  illustrates  a  typical 
drawn-bronze  window  as  used 
in  the  Boston  Art  Museum, 
Mr.  Guy  Lowell,  architect. 

Drawn-bronze  sash  may  also 
be  used  in  combination  with 
cast-  or  wrought-iron  frames, 
etc.  Thus  Fig.  129  illustrates 
a  portion  of  the  new  Grand 
Central  Station  Building,  New 


FIG.  130—  Detail  of  Sash  and  Frame, 
Grand  Central  Station  Building, 
N.  Y. 

York,  Warren  and  Wetmore, 
architects,  in  which  the  sash, 
stop  beads,  etc.,  are  of  drawn- 
bronze,  while  the  frames,  mul- 
lions,  facias,  etc.,  are  of  cast- 
iron.  A  detail  of  the  frame 
and  sash  is  indicated  in  Fig. 
130. 

Automatically  Closing 
Windows.  —  Sash  so  arranged 
as  to  close  automatically  and 
lock  under  fire  by  the  fusing  of 
a  link  or  other  means  to  accom- 
plish the  same  result,  should  be 
provided  when  the  conditions 
warrant.  This  to  be  deter- 
mined by  the  Underwriters 
having  jurisdiction. 

The  fusible  device  should  be 
outside  of  the  window  when  it 

is  open  and  in  position  to  receive  the  direct  heat  from  exposing 
fire.      Attachments  for  opening   or  holding   the   window   open 


FIG. 


131.  —  Automatically     Closing 
Sheet-metal  Window. 


450         FIRE    PREVENTION    AND    FIRE    PROTECTION 

should  not  interfere  with  the  action  of  the  automatic  device  or 
prevent  the  sash  from  closing. 

Fig.  131  illustrates  a  window  made  by  S.  H.  Pomeroy  Com- 
pany, Inc.,  with  pivoted  upper  and  lower  sash,  arranged  to  close 
automatically  by  the  release  of  fusible  links. 

Mullioned  Windows.  —  The  construction  of  mullioned 
sheet-metal  windows  has  passed  through  various  stages  of  de- 
velopment, all  for  the  better.  First,  the  mullion  was  built  of 
hollow  sheet-metal  similar  to  the  mullion  in  an  ordinary  wooden 
window.  Second,  to  reinforce  this  construction,  steel  structural 
shapes,  such  as  tees,  channels  or  beams,  were  placed  within  the 
mullions  for  added  strength  and  stiffness.  Third,  and  as  at 
present  called  for  by  the  rules  of  the  National  Board  of  Fire 
Underwriters,  all  windows  exceeding  5  feet  by  9  feet  in  size  (the 
limiting  dimensions  for  single  windows),  are  divided  by  mullions 
into  areas  not  exceeding  the  aforesaid  limit,  and  such  mullions 
are  reinforced  by  I-beams  properly  fireproofed. 

I-beams  to  be  securely  fastened  into  the  brickwork,  proper 
allowance  being  made  for  expansion  of  the  beams  when  heated. 

In  new  buildings  the  reinforcing  members  should  be  in- 
stalled as  the  building  is  erected. 

The  depth  of  the  I-beam  to  be  not  less  than  5  inches. 
This  should  be  increased  where  the  openings  are  in  excess  of 
9  feet. 

I-beam  to  be  provided  with  at  least  2  inches  of  tile,  con- 
crete or  other  approved  material  on  the  flanges  and  at  least  2J 
inches  next  to  the  web.  The  amount  of  fireproofing  next  to 
the  web  should  be  increased  on  large  beams. 

Metal  frames  to  be  securely  attached  to  the  reinforcing 
members. 

In  most  cases  the  reinforcing  members  should  be  thor- 
oughly enclosed  by  the  metal  parts  of  the  frames,  care  being 
taken  to  rivet  or  otherwise  fasten  the  parts  at  points  of  junc- 
tion so  as  to  resist  fire.  Purely  ornamental  parts  may  be  fas- 
tened by  soldering. 

In  view  of  the  experience  gained  in  the  Baltimore  and  San 
Francisco  conflagrations,  the  next  rational  step  in  the  design  of 
mullioned  windows  will  be  to  discontinue  entirely  the  use 
of  metal  mullions  or  metal  in  mullions,  and  to  employ  only 
solid  masonry  mullions,  for  reasons  more  fully  explained  in 
Chapter  XX. 

Wire  Glass  in  Windows.  —  The  different  kinds  and  patterns 
of  wire  glass,  available  sizes  and  thicknesses,  and  general  fire- 


FIRE-RESISTING    WINDOWS,    SHUTTERS   AND    DOORS      451 

resisting  properties  have  been  described  in  Chapter  VII  (see 
page  264). 

When  used  in  window  construction,  the  rules  and  require- 
ments of  the  National  Board  of  Fire  -Underwriters  should  be 
carefully  followed.*  The  more  important  rules  are  those  per- 
taining to  the  allowable  sizes  of  lights,  and  to  the  bearing  of 
lights  in  rabbets  or  stops,  as  per  requirements  a  and  b  on 
page  443. 

The  radiation  of  heat  through  wire  glass,  and  the  possible 
danger  to  trim  or  contents  of  a  building  arising  therefrom,  are 
points  about  which  there  is  more  .or  less  difference  of  opinion, 
depending  upon  the  view-point.  Thus  it  is  often  claimed  that 
firemen  or  occupants  frequently  place  too  much  reliance  upon 
wire  glass  windows,  which,  because  generally  considered  fire- 
resistive,  are,  therefore,  thought  to  be  all  sufficient  in  case  of  ex- 
posure, with  the  result  that  precautions  are  not  taken  to  prevent 
disastrous  radiation  of  heat  through  the  panes.  An  example 
may  be  quoted  of  a  fire  in  Boston,  1911,  which  cost  the  insurance 
companies  $15,000  for  water  damage  in  a  large  department  store 
because  a  wire  glass  window,  overlooking  an  exposure  fire,  was 
not  guarded  on  the  inside  by  the  firemen.  A  wooden  partition 
very  near  the  window  caught  fire,  and  the  injudicious  use  of  the 
standpipe  hose  by  employees  caused  the  large  water  damage 
previously  mentioned,  when  a  chemical  extinguisher,  properly 
used,  would  have  sufficed. 

Also,  the  radiation  of  heat  through  wire  glass  windows  may 
be  very  objectionable  in  sprinklered  risks,  as  many  heads  might 
operate  before  the  fire  danger  was  imminent.  On  the  other 
hand,  wire  glass  windows  have  formed  a  great  step  in  the  direc- 
tion of  universal  window  protection,  and  their  use  should  em- 
phatically be  encouraged.  It  is  probably  safe  to  say  that,  at 
least  in  a- great  majority  of  cases  where  wire  glass  windows  are 
used,  radiant  heat  from  an  exposure  fire  need  not  be  given  serious 
consideration,  as  the  exposure  will  not  be  either  sufficiently  near 
or  sufficiently  severe. 

Both  tests  and  experience,  however,  have  demonstrated  that 
the  radiation  of  heat  through  ordinary  wire  glass  windows  may, 
under  conditions  of  severe  exposure  at  short  range,  be  sufficient 
to  ignite  combustible  contents,  or  even  trim,  as  in  the  case  just 
cited.  In  the  tests  undertaken  by  the  British  Fire  Prevention 
*  See  pamphlet  "  Wired  Glass,"  issued  gratis  by  the  Board. 


452         FIRE    PREVENTION    AND    FIRE    PROTECTION 

Committee,  described  under  a  following  heading,  the  introductory 
notes  state  as  follows: 

Red  Book,  No.  113.  —  The  test,  to  which  these  protected 
windows  were  subjected,  was  more  severe  than  would  be  the 
case  in  an  actual  fire,  as  windows  would  then  face  a  fire  burning 
in  the  open  air  and  not  in  an  enclosed  chamber. 

The  radiation  of  heat  through  the  shutter  was  considerable. 
The  thermometer  on  the  inside,  8J  inches  from  the  glass,  in  35 
minutes  registered  166°  F.  when  the  inside  temperature  was 
1240°  F. 

The  radiation  of  heat  through  the  wired  plate  glass  in 
the  teak  sash,  as  registered  by  the  thermometer  suspended  in  a 
corresponding  position  to  that  previously  described,  reached  in 
55  minutes,  260°  F.,  with  an  inside  temperature  of  1420°  F. 

Red  Book,  ^No^  116.  —  Although  flame  did  not  pass 
through  the  glazing  in  5  out  of  the  6  window  openings  under 
test,  the  radiation  of  heat  raised  the  temperature  on  the  side 
opposite  to  the  fire  above  the  ignition  point  of  textiles,  suggest- 
ing the  provision  of  double  glazing  or  double  casements  or 
frames  in  positions  liable  to  be  exposed  to  fierce  flame  or  great 
heat. 

Practical  tests  made  by  underwriters  have  also  shown  that 
inflammable  merchandise,  such  as  cotton,  may  be  ignited  by 
heat  passing  through  ordinary  wire-glass  windows,  but  that, 
when  the  wire  glass  is  made  double,  with  an  air  space  between, 
ventilated  to  the  outside  air,  cotton  may  be  placed  within  four 
inches  of  the  glass  and  exposed  to  a  temperature  of  2500  degrees 
for  half  an  hour,  without  ignition.*  These  considerations  have 
given  rise  to  "Twin  Windows,"  or 

Double-glazed  Sash,  which  are  made  in  a  variety  of  forms  — 
stationary  sash,  hinged,  double  hung  or  pivoted  or  combinations 
of  these.  An  ordinary  type  with  fixed  lower  sash  and  pivoted 
upper  sash  is  shown  in  Fig.  132.  Each  sash  is  so  made  as  to 
hold  a  fixed  light  of  wire  glass,  and  also  a  removable  frame  con- 
taining another  light  of  wire  glass,  above  and  below  which  are 
rows  of  ventilation  holes.  This  removable  frame  is  an  improve- 
ment over  the  earlier  methods  of  double  glazing,  as  prior  to  this 
arrangement  there  was  no  way  of  cleaning  the  glass  on  the  inside 
faces.  The  National  Board  rules  regarding  double-glazed  sash 
are  as  follows : 

To  comply  essentially  with  the  specifications  for  single- 
glazed  sash,  and  to  be  used  when  the  contents  of  the  building 

*  See  Proceedings  of  Fourth  Annual  Meeting  of  National  Fire  Protection 
Association,  page  128, 


FIRE-RESISTING   WINDOWS,    SHUTTERS   AND   DOORS      453 


are  inflammable  and  the  exposure  severe.  The  application  of 
this  rule  to  be  at  the  discretion  of  the  Underwriters  having 
jurisdiction.  The  air-space  between  the  two  thicknesses  to  be 
at  least  one  (1)  inch  and  be  provided  with  suitable  ventilation 
at  the  top  and  bottom.  Where  two  or  more  sashes  are  used, 
one  above  the  other,  the  air-spaces  between  the  sheets  of  glass 
to  be  arranged  to  be  connected  when  the  window  is  closed. 


FIG.   132.  —  Double-glazed  Sash. 

In  case  of  severe  exposure,  inflammable  contents  within 
36  inches  of  the  window  would  be  in  danger  of  ignition  by  the 
heat  radiated  through  a  single  wired  glass  window.  With  the 
ventilated  double-glazed  sash  36  inches  could  be  allowed,  but  in 
case  the  single-glazed  sash  is  used  the  intervening  distance  be- 
tween the  window  and  the  merchandise  or  inflammable  material 
should  be  at  least  48  inches. 

The  desired  distance  of  inflammable  contents  from  the 
windows  may  be  secured  by  proper  guards  arranged  so  as  not 
to  obstruct  access  to  the  windows.  Guards  constructed  of  iron 
piping  are  recommended. 

Fire  Tests  of  Wire  Glass  Windows.  —  Fire  test  No.  78  of 

the  British  Fire  Prevention  Committee,  made  May  2,  1906  (see 


454         FIRE    PREVENTION    AND    FIRE    PROTECTION 

"Red  Bookj"  No:  113),  Was  to  ascertain  the  relative  fire-re- 
sistance of 

(a)  A  2-inch  deal  sash  glazed  with  plate  glass,  and  protected 
on  the  fire  side  by  a  Kinnear  steel  rolling  shutter,  size  4  feet  by 
4  feet  6  inches,  and 

(6)  A  3-inch  teak  sash  glazed  with  J-inch  wire  glass,  size 
2  feet  3  inches  by  4  feet  6  inches. 

Duration  of  test  one  hour,  temperatuie  increasing  to  1500°  F., 
followed  by  application  of  water  for  two  minutes. 

Summary  of  Test.  —  (a)  In  5  minutes  the  glass  began  to 
crack.  In  25  minutes  a  thermometer  placed  8^  inches  outside 
of  glass  registered  130°  F.  In  40  minutes  the  space  between 
.sash  and  shutter  was  filled  with  black  smoke.  In  47  minutes 
the  sash  burst  into  flame,  all  glass*  dropped  out,  and  sash  was 
destroyed.  After  the  test  the  shutter  was  raised,  to  within  2 
inches  of  the  top,  by  the  united  efforts  of  two  men. 

(6)  In  one  minute  the  glass  began  to  crack,  and  continued 
to  do  so  to  end  of  test.  In  20  minutes  smoke  came  over  head  of 
sash.  In  30  minutes  a  thermometer  placed  8J  inches  outside 
of  glass  registered  170°  F.  In  53  minutes  the  upper  part  of 
sash  was  glowing  on  the  outside.  In  60  minutes  the  sash  burst 
into  flame  on  the  outside.  On  the  application  of  water,  the 
force  of  the  stream  displaced  the  glass  and  it  fell  outwards,  but 
the  glass  held  together. 

This  comparative  test  would  seem  to  settle  the  relative  value 
of  combustible  windows  with  wire  glass,  protected  by  rolling 
shutters,  and  fire-resisting  windows  glazed  with  Wire  glass  —  to 
the  decided  advantage  of  the  latter. 

Fire  tests  Nos.  82  and  83  of  the  same  Committee,  made  July 
18,  1906,  are  described  in  "  Red  Book,"  No.  116.  These  tests 
were  to  compare  the  relative  fire-resistance  of  six  wire  glass  win- 
dow constructions,  subjected  to  a  temperature  of  1500°  to 
1650°  F.,  followed  by  the  application  of  water  for  two  minutes, 
openings  Nos.  1,  2  and  3  being  exposed  for  45  minutes,  and 
openings  4,  5  and  6  for  90  minutes. 

Summary  of  Tests.  —  Immediately  on  lighting  the  gas,  the 
glass  in  each  opening  commenced  to  crack  in  various  directions 
and  continued  to  do  so  during  the  test. 

Opening  No.  1  (2  feet  3  inches  by  4  feet  6  inches  in  size) 
was  filled  in  with  a  teak  frame  divided  into  two  squares,  into 
which  the  glass  was  fixed  with  teak  beads.  Fire  did  not  pass 
through  the  glass,  but  smoke  passed  between  the  glass  and 
frame.  The  upper  part  of  frame  was  charred  on  the  outside, 
and  at  conclusion  of  test  burst  into  flame.  The  glass  remained 


FIRE-RESISTING    WINDOWS,    SHUTTERS   AND   DOORS      455 

in  position  after  the  application  of  water,  but  subsequently  the 
lower  square  fell  out  on  being  tapped,  but  remained  unbroken. 

Opening  No.  2  (2  feet  3  inches  by  4  feet  6  inches  in  size)  was 
filled  in  with  a  steel  channel-iron  frame  with  one  fixed  and  one 
side-pivoted  angle-iron  sash,  each  containing  one  light  of  plate 
wire  glass.  Fire  did  not  pass  through  the  glass.  The  steel 
frame  and  sash  were  uninjured,  but  slightly  twisted.  The  glass 
remained  in  position.  Smoke  passed  between  the  frame  and 
surrounding  brickwork,  and  between  the  meeting  rails  of  sash. 

Opening  No.  3  (2  feet  3  inches  by  4  feet  6  inches  in  size)  was 
filled  in  with  a  galvanized  sheet-steel  frame  and  double-hung 
sash,  each  of  which  was  divided  by  a  muntin.  The  upper  sash 
contained  maze  wire  glass,  the  lower  sash  polished-plate  wire 
glass.  Fire  did  not  pass  through  the  glass.  The  frame  and  sash 
were  intact  and  the  glass  in  position.  Smoke  passed  between  the 
frame  and  brickwork. 

Classification  was  obtained  as  affording  " temporary  pro- 
tection, Class  A,"  see  Chapter  V,  page  116. 

Opening  No.  4  (2  feet  6  inches  by  2  feet  6  inches  in  size)  was 
filled  with  one  square  of  J-inch  maze  wire  glass,  fixed  directly 
into  the  brick  reveal  by  being  imbedded  in  a  composition  of 
asbestos  and  plaster.  Neither  fire  nor  water  passed  through 
the  glass.  There  was  a  bulge  inwards  of  about  J  inch.  Classi- 
fication obtained,  " partial  protection,  Class  A." 

Opening  No.  5  (2  feet  3  inches  by  4  feet  6  inches  in  size) 
was  filled  in  with  a  steel  channel-iron  frame,  with  two  steel 
angle-iron  sash,  the  upper  one  being  fixed  and  containing  i-inch 
rolled-plate  wire  glass,  the  lower  one  being  pivoted  at  sides  and 
containing  j-inch  polished-plate  wire  glass. 

At  the  expiration  of  60  minutes  the  glass  in  the  opening 
was  intact,  but  cracked.  In  65  minutes  the  glass  in  upper  sash 
began  to  bulge.  In  70  minutes  the  glass  in  lower  casement 
began  to  bulge.  In  84  minutes  the  glass  in  upper  sash  had 
drawn  sufficiently  out  of  rebate  to  let  flame  through,  and  in 
87  minutes  the  glass  in  lower  sash  did  likewise.  On  the  applica- 
tion of  water  the  glass  remained  in  the  sash,  although  damaged 
and  bulged. 

Opening  No.  6  (2  feet  3  inches  by  4  feet  6  inches  in  size) 
was  filled  in  with  a  hollow  galvanized  sheet-steel  frame  and  sash, 
identical  'with  opening  No.  3.  Neither  fire  nor  water  passed 
through  the  glass.  Classification  "partial  protection,  Class  A" 
was  obtained. 

These  tests  show  the  decided  superiority  of  hollow  sheet-metal 
windows  over  any  constructions  made  up  of  steel  shapes. 

Wire  Glass  Windows  in  San  Francisco  Fire.  —  Previous 
mention  has  been  made  of  the  saving  of  the  Western  Electric 
Company's  Building  in  the  San  Francisco  fire  (see  report  of 
Mr.  S.  Albert  Reed,  page  424);  and  as  this  example  forms  a 


456         FIRE    PREVENTION   AND    FIRE   PROTECTION 

most  interesting  instance  of  the  protection  which  may  be  afforded 
by  wire  glass  windows,  it  is  worth  considering  in  more  detail. 

The  building,  a  four-story  mill-constructed  warehouse  and 
factory,  is  shown,  looking  in  a  westerly  direction,  in  Fig.  133. 
All  windows,  except  those  in  an  office  portion  on  the  fourth  floor, 
were  of  wire  glass  in  metal  frames.  To  the  northeast  was  a 


FIG.  133.  —  Western  Electric  Co.'s  Building  after  San  Francisco  Conflagration. 

blank  brick  wall,  save  two  shipping  doors  at  the  first  floor  which 
were  protected  by  tin-covered  sliding  fire  doors  (see  photograph). 
The  building  was  equipped  with  sprinklers,  supplied  by  a  50,000- 
gallon  roof  tank  as  shown,  while  a  secondary  supply  consisted 
of  a  120,000-gallon  reservoir  under  the  yard,  with  an  electrically- 
driven  rotary  pump.  The  following  interesting  description  of 
the  fire  is  from  a  report  made  by  Mr.  A.  W.  Hitchcock,  Insurance 
Engineer  of  the  Western  Electric  Company. 

Immediately  following  the  earthquake,  fire  broke  out  in 
the  dwelling  houses  just  north  of  Section  A.*  The  department 
responded,  but  had  absolutely  no  water  from  their  mains,  and 
fought  the  fire  with  the  water  taken  from  the  property  hydrants. 
In  this  way  the  50,000-gallon  tank  was  emptied  early  in  the  day 
and  left  the  sprinklers  with  no  supply  of  water  back  of  them. 
This  appears  to  have  been  a  good  thing,  in  that  no  water  dam- 

*  Section  A  comprises  that  portion  of  building  to  left  of  entrance  doorway 
shown  in  photograph,  and  section  B  the  larger  portion  nearer  the  observer. 
A  brick  fife  wall  separated  the  two  sections. 


FIRE-RESISTING   WINDOWS,    SHUTTERS  AND   DOORS      457 

age  from  the  sprinklers  resulted  later.  The  earthquake,  be- 
sides cutting  off  the  supply  of  water  in  the  street  mains,  wrecked 
the  power  house  so  that  there  was  no  electric  current  available 
for  use  with  the  rotary  pump. 

The  fire  spread  in  both  an  easterly  and  a  westerly  direction, 
wiping  out  during  the  morning  all  of  the  exposure  north  of  the 
plant  and  west  of  Hawthorne  street.  It  did  not  communicate, 
however,  across  Hawthorne  street  at  this  time,  nor  did  it  cross 
California  street  to  the  dwellings  at  the  west  of  Section  A. 

After  the  fight  with  the  exposures  at  the  north,  the  fire  de- 
partment, some  time  about  noon,  left  the  immediate  vicinity  to 
do  duty  elsewhere. 

After  noon  the  conflagration  began  to  work  back  toward 
Third  street  from  the  west,  and,  jumping  Third  street,  attacked 
the  block  of  houses  on  the  west  of  the  property.  The  employees 
finally,  after  considerable  effort,  succeeded  in  persuading  the 
fire  department  working  on  Third  street  that  there  was  a  large 
reservoir  under  our  yard,  and  they  finally  brought  a  fire  engine 
and  dropped  its  suction  into  our  120,000-gallon  yard  reservoir. 
With  the  water  thus  obtained  they  proceeded  to  fight  the  row 
of  dwellings  on  the  east  side  of  Third  street.  Their  efforts 
were  unsuccessful,  and  when  the  fire  finally  caught  the  5-story 
dwelling  house  against  Section  A  they  gave  up  and  left,  saying 
that  the  California  Electrical  Works  was  doomed. 

At  about  four  o'clock  in  the  afternoon,  when  this  occurred, 
the  fire  had  begun  to  work  in  on  the  south  side  of  Folsom  street 
along  the  houses  shown,  and  the  superintendent  instructed  the 
employees  to  leave  before  they  were  completely  surrounded. 
This  they  did  with  the  exception  of  two  men,  one  of  them,  the 
building  superintendent,  sticking  to  the  property  until  all  danger 
to  the  building  was  past. 

It  is,  therefore,  clear  that  during  the  severest  part  of  the 
fire,  that  is,  during  the  last  part  of  the  destruction  of  the  5-story 
building,  there  were  only  two  men  on  the  property  and  there 
was  no  water  available  except  a  small  amount  in  the  mill  tank. 

In  addition  to  the  5-story  building,  there  were  two  car- 
loads of  fir  cross  arms  for  telephone  poles  stored  against  the 
property  wall  on  the  west  side  of  Section  A.  These  burned  up, 
together  with  such  material  as  was  being  shipped  and  stood  on 
the  shipping  platform. 

During  this,  the  hottest  part  of  the  fire,  a  few  pails  of 
water  were  carried  up  onto  the  roof  from  the  toilets  in  the  fifth 
floor  of  A,  and  the  exposed  beams  and  the  woodwork  of  the 
drawing  room  went  down  as  they  caught  fire.  The  inflammable 
material  was  drawn  away  from  the  windows  as  the  heat  grew 
intense,  smoking  curtains  pulled  down,  etc.,  but  desks  were 
badly  scorched,  and  on  the  fourth  floor  a  switch-board  cable 
required  a  pail  of  water  from  the  hand  of  one  of  the  employers. 

On  each  floor  on  the  west  side  of  A,  the  sprinkler  heads 
nearest  the  windows  were  opened  by  the  heat,  but  the  next 
heads  inside,  which  are  about  15  feet  from  the  wall,  were  not 


458        FIRE   PREVENTION   AND   FIRE   PROTECTION 

opened.  The  galvanized-iron  frames  of  the  wire  glass  the 
whole  length  of  this  wall  had  the  paint  all  blistered  off,  but  they 
were  not  sprung  by  the  heat  in  any  case  more  than  half  an 
inch,  and  in  most  cases  not  at  all.  The  wire  glass  stogd  up 
in  every  case,  and  shows  that  it  went  through  only  by  large 
diagonal  cracks.  Nowhere  did  the  glass  sag  in  the  frame. 


FIG.    134.  —  Wire  Glass  Windows  in  Western  Electric  Co.'s    Building  after 
Conflagration. 

On  the  east  side  of  Section  B  in  the  yard  there  were  stored 
a  quantity  of  empty  barrels  and  boxes.  These  were  destroyed, 
and  charred  the  tin-clad  doors  into  the  first  floor,  but  the  doors 
did  not  give  way,  nor  was  the  fire  communicated  into  the  build- 
ing through  the  openings. 

Conclusions.  —  Undoubtedly  the  California  Electrical 
Works  would  not  be  standing  to-day  if  the  windows  had  not 
been  of  wire  glass  in  metal  frames.  Undoubtedly  also  it  would 
be  a  ruin  had  not  the  employees  remained  in  the  building.  But 
it  is  equally  true  that  neither  one  of  these  agencies  alone  saved  the 
day,  and  if  the  men  had  not,  been  there,  heat  passing  through 
the  wire  glass  would  have  started  an  interior  fire  and  destroyed 
the  building;  or,  if  there  had  been  no  wire  glass,  the  men  with 
practically  no  water  would  have  been  entirely  inadequate  to 
grapple  with  the  proposition. 


FIRE-RESISTING   WINDOWS,    SHUTTERS  AND   DOORS      459 

One  of  the  triple  windows  to  be  seen  in  Fig.  133  is  shown, 
looking  from  inside  of  building,  in  Fig.  134. 

That  wire  glass,  however,  is  subject  to  complete  destruction 
under  severe  conditions,  is  shown  by  Fig.  135  which  illustrates 


FIG.  135.  —  Court  of  Wells-Fargo  Building,  San  Francisco,  after  Conflagration. 

the  condition  of  the  interior  court  of  the  Wells-Fargo  Building 
after  the  San  Francisco  fire.  This  photograph  also  shows  the 
failure  of  the  glazed  terra-cotta  tiling  used  in  the  court  walls. 

Prism  Glass  Windows.  —  The  fire-resisting  properties  of 
prism  glass,  especially  when  electro-glazed,  have  previously  been 
discussed  in  Chapter  VII,  page  267.  Several  fire  tests,  both 
experimental  and  actual,  on  both  ordinary  glazed  and  electro- 
glazed  prism  glass  have  shown  that  these  constructions  may 
possess  considerable  value,  but  the  fire-resistance  offered  by  the 
prisms  is  principally  due  to  the  fact  that  the  glass  is  used  in 
small  lights,  held  at  their  entire  perimeter,  rather  than  to  any 
qualities  in  the  prisms  themselves.  Small  lights  of  plate  glass, 
say  4  inches  square,  when  electro-glazed,  also  possess  fire-resis- 
tance about  equal  to  prism  glass. 

An  interesting  photograph  showing  the  almost  perfect  con- 
dition of  Luxfer  prisms  in  the  transom  lights  over  the  demolished 
plate  glass  show  windows  of  the  McClurg  store  in  Chicago, 


4:60         FIRE   PREVENTION   AND   FIRE   PROTECTION 

destroyed  by  fire,  was  published  in  The  Insurance  Press, 
March  8,  1899. 

Electro-glazed  prism  windows  have  been  installed  in  a  number 
of  buildings  where  both  appearance,  added  light,  and  fire  pro- 
tection were  desiderata.  Thus  the  windows  on  a  side  alley  of 
the  Rookery  Building  in  Chicago  are  so  glazed,  also  the  windows 
on  one  of  the  narrower  street  fronts  of  the  mammoth  Prudential 
Life  Insurance  Company's  Building  in  Newark,  N.  J. 

The  conclusions  of  the  National  Board  of  Fire  Underwriters 
regarding  prism  glass  when  used  as  a  fire-retardant  are  as  follows : 

Prisms,  as  installed  for  the  purpose  of  increased  light,  are 
usually  not  contained  in  frames  which  are  designed  to  with- 
stand severe  heat,  as  the  requirements  for  strength  under  the 
different  conditions  of  actual  installation  do  not  necessitate  a 
frame  which  can  be  relied  on  as  a  fire-retardant. 

The  metallic  ribbons  between  the  prisms  used  for  the 
purpose  of  light  only  are  not  heavy  enough,  are  not  continuous 
and  unbroken  in  both  directions,  and  are  not  attached  to  the 
metal  border  securely  enough  to  withstand  severe  conditions  of 
heat.  The  ribbons  in  one  direction  are  usually  formed  of  short 
pieces  slipped  in  between  the  unbroken  ribbons  running  in  the 
opposite  direction,  and  are  held  in  position  by  solder. 

In  frames  for  this  service  the  ribbons  are  usually  of  com- 
paratively light  metal  and  are  fastened  to  the  metallic  border 
by  soldering. 

It  has  been  demonstrated  by  fire  tests  that  prism  frames 
constructed  as  described  do  not  possess  sufficient  fire-resisting 
properties  to  warrant  consideration.  But  where  constructed 
for  the  purpose  of  withstanding  severe  conditions  of  heat  they 
may  be  made  of  service. 

In  all  cases  where  electro-glazed  frames  are  to  be  installed 
as  a  protection  against  fire  they  should  be  specially  constructed 
for  this  purpose  and  framed  in  as  careful  and  secure  a  manner  as 
wired  glass.* 

Shutters  vs.  Wire  Glass  Windows.  —  Decided  objections 
to  the  extensive  use  of  outside  hinged  shutters  are  found  in  their 
unsightliness  and  their  annoyance  to  tenants. 

For  the  rear  or  side  walls  of  stores,  warehouses  and  the  like, 
outside  shutters  will  generally  be  unobjectionable;  but  for  prin- 
cipal facades,  or  in  buildings  occupied  by  many  tenants,  either 
the  appearance  or  the  annoyance  of  their  use  would  make  their 
installation  impracticable.  Thus  in  office  buildings  it  would 
be  almost  impossible  to  place  window  shutters  and  keep  them 

*  For  full  rules  and  requirements,  see  National  Board  of  Fire  Underwriters' 
pamphlet  "Wired  Glass." 


FIRE- RE  SI  STING   WINDOWS,    SHUTTERS   AND    DOORS      461 

closed,  even  were  the  appearance  not  objectionable.  There 
could  be  no  systematic  method  of  closing  them  without  giving 
serious  cause  .for  complaint  on  the  part  of  those  tenants  who 
wished  to  use  their  offices  for  night  work,  while  if  there  were  not 
some  inviolable  rule  regarding  their  closing,  their  mere  presence 
would  be  useless,  as  in  the  case  of  the  Vanderbilt  Building  fire, 
described  in  Chapter  VI. 

A  further  objection  to  outside  hinged  shutters,  inside  folding 
shutters,  and  to  outside  or  inside  rolling  shutters  (unless  normally 
open)  is  the  fact  that  if  all  such  shutters  are  closed  at  night,  an 
internal  fire  may  attain  serious  headway  before  even  the  presence 
of  fire  is  known  from  the  street.  This  has  occurred  a  number  of 
times  in  completely  shuttered  factory  buildings,  etc.,  and,  to 
prevent  such  an  occurrance,  the  Boston  Board  of  Fire  Under- 
writers requires  that,  where  shutters  are  used  at  all  openings, 
one  tier  of  windows  on  some  street  front  be  left  with  the  shutters 
open  to  allow  interior  fire  to  be  discovered.  The  chance  of  serious 
internal  fire  in  a  completely  shuttered  building  is  considered 
more  than  an  offset  to  the  chance  of  exposure  fire  entering  the 
tier  of  unshuttered  windows  before  the  shutters  could  be  closed. 

Rolling  shutters  of  the  normally  open,  automatic  type  do 
not  possess  the  objections  above  stated  as  applying  to  hinged 
shutters,  and  the  fact  that  they  are  always  open  makes  them 
unobjectionable  in  appearance,  while  the  automatic  release 
insures  their  being  ever  ready  in  time  of  emergency.  Their 
behavior  in  the  San  Francisco  fire,  especially  in  the  Bush  Street 
Telephone  Building  before  described,  shows  them  to  be  as 
efficient  as  any  other  single  form  of  window  protection. 

Wire  glass  windows  are  pleasing  in  appearance,  —  more  gen- 
erally applicable  to  average  conditions  than  shutters  —  always 
in  place  and  ready  for  service,  —  but  subject  to  limitations  of 
exposure  a_s  has  previously  been  pointed  out.  They  must  be  used 
with  great  caution  in  sprinklered  risks,  as  radiated  heat  might 
cause  far  more  water  damage  than  would  result  from  fire  damage. 

Window  Protection  as  Recommended  by  Various  Au- 
thorities. —  The  recommendations  of  Mr.  S.  Albert  Reed  have 
previously  been  given  (see  page  423). 

After  the  Baltimore  fire,  Mr.  John  R.  Freeman  made  the 
following  recommendations:* 

*  From  address  at  annual  banquet  of  the  National  Board  of  Fire  Under- 
writers, May,  1904. 


462         FIRE    PREVENTION   AND   FIRE    PROTECTION 

The  path  of  safety  from  exposure  fires  for  office  buildings 
and  the  like,  lies  in  a  window  casing  formed  so  that  we  can 
attach  to  it  a  shutter  of  a  form  similar  to  the  ordinary  house 
blind.  Our  ordinary  business  buildings  have  walls' thick  enough, 
so  that  by  making  the  shutter  in  four  folds,  or  leaves,  two 
being  hinged  together,  and  these  two  in  turn  attached  to  the 
wall,  making  each  fold  in  the  shutter  only  about  15  inches 
wide,  the  window  will  be  wide  enough  for  all  practical  purposes, 
and  we  can  fold  the  shutter  back  within  the  window  jamb, 
very  much  as  we  do  the  inside  blind. 

To  do  that  with  the  present  ordinary  tin-clad  shutter 
would  be  almost  impossible,  because  of  the  thickness  of  that 
form  of  shutter.  It  can  be  done  with  a  steel  plate  shutter, 
without  ribs,  and  the  radiation  can  be  checked  by  some  thin 
incombustible  porous  covering  like  asbestos  board.  .  .  . 

It  is  entirely  possible  to  design  a  window  opening  adapted  to 
receive  a  safe  shutter,  so  that  it  will  be  just  as  convenient  for 
ordinary  business  purposes  as  the  type  now  common.  I  think 
it  probable  that  the  best  place  for  the  shutters  is  inside  the 
glass,  sacrificing  the  glazed  sash  outside  them  in  case  of  any 
great  conflagration.  .  .  . 

In  short,  if  you  want  to  provide  against  an  exposure  fire,  I 
believe  the  only  way  to  do  it  is: 

First,  by  a  wall  either  of  brick  or  concrete, 

Second,  by  properly  designed  window  openings  and  cas- 
ings, and 

Third,  by  good  shutters  in  those  windows. 

As  a  result  of  extensive  investigations  regarding  the  San 
Francisco  conflagration,  Captain  Sewell  reported  as  follows:* 

While  there  is  no  doubt  that  commercial  standards  of  fire  - 
proofing  are  dangerously  inadequate,  the  greatest  trouble  of 
all  is  the  fact  that  so  little  attention  is  paid  to  protecting  the 
exterior  openings  in  a  building.  Even  a  very  inefficient  type 
of  fire  shutter  would  probably  have  saved  some  of  the  buildings 
in  San  Francisco,  which  were,  as  a  matter  of  fact,  burned  out. 
A  light  metal  shutter  combined  with  a  window  sprinkler  would 
probably  resist  a  rather  fierce  fire  for  a  long  time.  Although 
the  failure  of  the  water  supply  in  San  Francisco  might  be  urged 
as  one  reason  why  a  window  sprinkler  would  have  been  of  no 
avail,  it  is  a  fact  that  water  can  be  obtained  by  driving  wells 
into  the  sand  which  underlies  the  business  portion  of  San  Fran- 
cisco almost  everywhere.  Under  these  circumstances,  if  the 
fireproof  buildings  had  been  fitted  with  metal  shutters,  even  no 
better  than  those  in  the  windows  of  the  Hall  of  Records,  and  if 
each  window  had  been  provided  with  a  sprinkler  and  the  build- 
ing itself  with  its  own  well  and  fire  pump,  it  is  probable  that  the 
fire  could  have  been  kept  out  of  a  large  number  of  the  buildings. 
The  protection  of  external  openings  is  by  all  odds  the  most  im- 

*  See  Bulletin  No.  324,  pages  122  and  123. 


FIRE-RESISTING    WINDOWS,    SHUTTERS    AND    DOORS      463 

poil ant  constructive  problem  involved  in  the  efforts  to  make 
cities  proof  against  conflagration,  and  it  seems  probable  that  at 
the  present  time  adequate  protection  of  windows  and  doors  is 
available  at  a  reasonable  cost.  In  my  judgment,  windows  pro- 
tected in  the  following  way,  even  without  sprinklers,  might  keep 
out  the  fire,  though  the  buildings  were  shut  up  and  abandoned. 

1.  The  outer  opening  should  be  protected  with  some  form 
of  rolling  steel  shutter  or,  preferably,  with  a  shutter  composed 
of  sheets  of  steel  sliding  in  very  deep  rebates  in  the  walls.     The 
sheets  of  steel  should  be  anchored  in  these  rebates  by  means  of 
angle  irons  or  rivets  driven  so  as  to  interlock  with  a  bead  to  be 
placed  in  position  after  the  sheet  of  steel  is  itself  in  position. 
By  providing  a  pocket  in  the  masonry  just  above  the  window 
head  and  making  these  shutters  in  three  or  four  parts,  overlap- 
ping and  interlocking  at  the  overlap,  the  whole  shutter  could  be 
slid  up  into  the  wall  practically  out  of  sight.     This  arrangement 
would  necessitate  window  openings  slightly  lower  than  those 
used  in  many  commercial  buildings,  but  the  loss  of  light  would 
not  be  very  serious.     The  metal  shutters  when  closed  should 
overlap  the  window  opening  in  all  directions  by  at  least  6  inches. 
This   overlapping   could   be   accomplished   at   the   sill   without 
making  a  pocket  to  catch  water  and  dust,  by  forming  a  step  in 
the  sill  itself. 

2.  The  windows  should  be  made  entirely  of  wire  glass, 
with  sheet-metal  or  metal-covered  sash,  hung  in  metal  or  metal- 
covered  frames.     Clear  wire  glass  can  be  used  if  desired. 

3.  On  the  inside  of  the  window  there  should  be  a  sliding 
shutter,  either  of  wood  covered  with  sheet  metal  or  of  sheet 
metal  such  as  that  described  for  the  outside.     If  the  outer  wall 
is  furred,  a  pocket  could  be  made  between  the  furring  and  the 
wall,  so  that  the  inside  shutters  could  be  slid  sidewise. 

It  is  probable  that  under  a  fairly  bad  exposure  to  fire  the 
outer  shutters  here  described  would  be  so  damaged  that  they 
would  have  to  be  removed.  In  a  conflagration  they  would 
probably  be  warped  to  such  an  extent  as  to  let  the  heat  in,  and 
possibly  to  soften  the  wire  glass  and  damage  the  windows  them- 
selves, so  that  they  also  might  have  to  be  renewed  —  at  least 
so  far  as  the  sash  were  concerned.  But  it  is  very  doubtful  if 
any  conflagration  would  ever  get  through  the  sash,  much  less 
through  the  inside  shutters.  Any  damage  to  the  window  pro- 
tection,  however,  would  be  a  very  small  matter  compared  with 
the  total  destruction  of  the  contents  of  the  building  and  a 
damage  of  65  to  80  per  cent,  to  the  building  itself. 

Window  protection  of  the  kind  just  described  could  be  so 
designed  that  it  would  not  be  objectionable  even  on  the  prin- 
cipal fronts  of  buildings.  The  San  Francisco  and  Baltimore 
fires  have  demonstrated  that  all  the  exterior  openings  of  even 
fireproof  buildings  need  protection.  It  would  seem  that  the 
time  has  arrived  when  building  ordinances  should  require  it. 

If  to  the  triple-window  protection  described  above,  a  win- 
dow sprinkler  with  adequate  water  supply  is  added,  a  defense, 


464         FIRE    PREVENTION    AND    FIRE    PROTECTION 

which  will  probably  not  only  be  adequate  for  its  purpose, 
but  which  will  suffer  small  damage  itself,  will  be  provided. 
This  system  of  protection,  while  it  has  never  been  applied,  can 
be  applied  at  a  cost  which  is  not  prohibitive,  especially  if  un- 
necessary and  expensive  finish  is  omitted. 

Selection  of  Window  Protection.  —  A  choice  of  the  several 
types  of  window  protection  which  have  been  considered  will 
involve  the  questions  of  distance  in  exposure,  severity  of  ex- 
posure, appearance,  and  efficiency  of  protection  contemplated, 
maintenance  of  same,  and  first  cost. 

If  the  exposure  is  very  light,  as  in  buildings  of  good  con- 
struction across  a  street  as  wide  as  100  feet,  open  sprinklers 
should  be  sufficient,  except  for  a  risk  particularly  dangerous  in 
itself. 

If  the  exposure  is  moderate,  say  at  a  distance  of  50  to  75  feet, 
and  the  building  is  not  especially  hazardous  in  itself,  wire  glass 
windows  would  be  preferable. 

If  the  exposure  is  severe  and  at  a  distance  of  say  40  to  50  feet, 
tin-covered  shutters  should  be  used  where  the  appearance  is  not 
essential;  or,  if  such  shutters  are  objectionable,  rolling  steel 
shutters,  or  wire  glass  windows  with  open  sprinklers  could  be 
used. 

If  the  exposure  is  both  near  and  severe,  and  appearance  need 
not  be  considered,  tin-covered  shutters  in  combination  with 
either  wire  glass  windows  or  open  sprinklers  may  be  used;  or, 
where  appearance  must  be  considered,  either  inside  or  rolling 
steel  shutters  in  combination  with  wire  glass  windows  would 
be  efficient,  or  rolling  steel  shutters  and  open  sprinklers. 

Of  course,  the  above  recommendations  are  merely  suggestive. 
Each  building  is  more  or  less  a  problem  unto  itself,  according  to 
its  construction,  occupancy,  exposure,  etc.,  but  the  minimum 
degree  of  window  protection  to  be  accorded  each  exposure  must 
not  fall  below  the  requirements  of  the  Underwriters  having 
jurisdiction.  The  experience  of  the  past,  however,  shows  that 
it  is  often  advisable  to  exceed  such  requirements  rather  than 
seek  to  evade  them. 

The  present  practice  of  the  New  York  Fire  Insurance  Ex- 
change regarding  allowances  for  the  installation  of  approved 
shutters  or  wire  glass  windows,  or  both,  is  as  follows:  * 

*  See  circular  of  New  York  Fire  Insurance  Exchange  dated  January  2,  1912. 


FIRE-RESISTING    WINDOWS,    SHUTTERS   AND    DOORS      465 

Exposure  Table.  —  The  Rate  Committee  rules  that  hereafter 
the  office  is  to  apply  the  provision  in  the  exposure  table  of  the 
Exchange  for  reduction  of  exposure  charge  for  presence  of  ap- 
proved fire  shutters,  so  as  to  make  the  same  allowances  for  ap- 
proved wire  glass  windows  as  for  shutters,  and  to  increase  those 
allowances  by  one-half  when  both  standard  fire  shutters  and  ap- 
proved wire  glass  windows  are  present.  The  effect  of  this  ruling 
is  to  make  available  an  allowance  or  deduction  from  exposure 
charge  of  40  per  cent,  if  window  openings  of  risk  are  protected 
by  approved  fire  shutters  or  wire  glass  windows,  and  of  60  per 
cent,  if  they  are  protected  by  both  such  shutters  and  such  win- 
dows; an  allowance  of  33 J  per  cent,  where  window  openings  of 
exposure  are  protected  by  standard  fire  shutters  or  wire  glass 
windows,  and  of  50  per  cent,  if  so  protected  by  both  the  standard 
fire  shutters  and  the  approved  wire  glass  windows;  and  an  allow- 
ance of  45  per  cent,  where  window  openings  of  both  risk  and  ex- 
posure are  protected  either  by  standard  fire  shutters  or  wire  glass 
windows,  and  of  67|  per  cent,  if  protected  by  both.  But  in  order 
to  obtain  the  allowance  noted  above  for  wire  glass  windows,  in 
addition  to  or  without  the  shutters,  where  the  exposure  is  within 
30  feet  of  the  risk,  the  wire  glass  windows  must  be  of  the  double 
glazed  type;  if  the  exposure  be  adjoining  and  lower  than  the 
risk,  thus  constituting  overhead  exposure,  then  for  three  stories 
or  30  feet  above  the  exposure  wire  glass  windows  must  be  of  the 
double  glazed  type.  Beyond  a  distance  of  30  feet,  either  horizon- 
tal or  vertical,  a  single  glazing  is  the  equivalent  of  the  standard 
shutter,  but  within  that  distance  is  entitled  to  only  half  the  reg- 
ular allowance.  The  increased  allowance  provided  for  under  this 
rule  where  both  standard  shutters  and  approved  wire  glass  win- 
dows are  installed  will  not  apply  in  those  cases  where  the  wire  glass 
windows  are  single  glazed,  unless  the  exposure  be  more  than  30 
feet  distant. 


Costs  are  very  difficult  to  generalize,  as  so  much  depends  upon 
the  locality,  the  conditions  of  installation,  and  the  quantity 
ordered;  but  fair  average  prices  will  run  about  as  follows: 

Tin-covered  shutters,  installed  complete  with  all  necessary 
hardware;  30  cents  per  square  foot. 

Hollow  galvanized-iron  windows  glazed  with  rough,  ribbed  or 
figured  wire  glass,  about  75  cents  per  square  foot  for  pivoted 
windows,  and  about  one  dollar  per  square  foot  for  double-hung 
windows,  both  installed  complete.  Polished-plate  wire  glass 
may  be  taken  at  about  one  dollar  per  square  foot  additional. 

Copper  windows  will  average  about  75  cents  per  square  foot 
higher  than  galvanized-iron. 

The  cost  of  rolling  steel  shutters  will  depend  entirely  upon  the 
dimensions  of  openings,  difficulty  of  installation,  etc. 


466         FIRE    PREVENTION    AND    FIRE    PROTECTION 


FIRE-RESISTING  DOORS 

Consistent  construction  requires  that  fire-resisting  doors,  like 
windows,  should  not  be  materially  weaker  from  the  standpoint 
of  fire-resistance  than  the  partition  or  wall  in  which  they  are 
placed.  The  fact  that  but  one  inadequately  protected  door 
opening  may  prove  the  ruin  of  an  otherwise  impregnable  building, 
is  well  exemplified  in  the  case  of  the  Pacific  States  Telephone 
and  Telegraph  Company's  Building  in  the  San  Francisco  con- 
flagration, as  previously  described  in  this  chapter. 

Types.  —  Ordinary  types  of  fire-resisting  doors  include  tin- 
clad,  plate-iron,  composite,  or  iron  filled  with  some  fire-resisting 
material,  corrugated-iron,  rolling  steel  doors,  kalamine,  and  hol- 
low metallic.  Various  modifications  of  these  types  also  exist, 
as  will  be  pointed  out. 

The  best  type  for  use  in  any  particular  location  will,  princi- 
pally, be  dependent  upon  acceptability  to  Underwriters  having 
jurisdiction;  but  availability,  appearance  and  adaptability  will 
often  prove  determining  factors. 

For  interior  doors  in  factories,  warehouses  and  the  like,  or  in 
inconspicuous  locations  in  office  and  store  buildings,  etc.  (such 
as  boiler,  engine,  elevator-machine  rooms,  roof  houses,  etc.), 
tin-clad,  plate-  or  corrugated-iron  doors  are  generally  used. 
Where  appearance  is  a  factor  to  be  considered,  or  where  openings 
are  especially  large,  rolling  steel  or  composite  doors  are  often 
preferable;  or,  if  appearance  is  of  paramount  importance,  as 
for  stair  and  elevator  doors  in  office  buildings,  hotels,  etc.,  choice 
will  be  confined  to  rolling  steel,  kalamine  or  hollow-metallic 
doors. 

About  the  same  process  of  selection  will  apply  to  exterior 
doors.  For  small,  unimportant  openings,  tin-clad,  plate-  or 
corrugated-iron  doors  are  usual.  For  larger  or  better  appearing 
openings,  steel  rolling  doors  are  general,  while  for  conspicuous 
entrance  doors,  etc.,  kalamine  or  hollow  metallic,  or  solid  plate- 
or  cast-bronze  are  suitable. 

It  should  be  noted  especially  that  all  openings  in  fire  walls, 
i.e.,  walls  between  two  separate  buildings  or  fire  sections  of  a 
building,  require  doors  on  both  sides  of  such  openings  (see  later 
paragraph  "Double  Fire  Doors,"  page  489). 

Requisites  for  Fire  Doors.  —  The  advantages  and  disad- 
vantages of  various  types  will  be  discussed  in  following  para- 


FIRE-RESISTING    WINDOWS,    SHUTTERS   AND    DOORS      467 

graphs,  but  any  fire  door  to  be  acceptable  should  combine,  like 
fire  shutters,  the  requisites  of  fire-resistance  and  ability  to  resist 
excessive  radiation  of  heat.  The  adaptability  for  use  as  a  fire 
shield  by  firemen  in  fighting  fire  is  also  often  important.  To 
fulfil  this  requirement,  single  doors  in  fairies,  warehouses,  etc., 
should  be  provided  with  protected  hose  holes. 

Frames,  hardware,  and  methods  of  hanging  are  especially 
vital  points  in  connection  with  fire  doors.  For  full  rules  and 
regulations  concerning  the  making  and  hanging  of  tin-clad, 
plate-iron  and  steel  rolling  doors,  see  illustrated  pamphlet  "Fire 
Doors  and  Shutters"  issued  by  the  National  Board  of  Fire 
Underwriters. 

Tin-clad  Doors.  —  A  few  of  the  more  important  standard 
rules  concerning  tin-clad  doors  are  as  follows: 

Openings  in  Wall.  —  To  be  as  few  and  made  as  small  as 
the  nature  of  the  business  will  permit,  but  in  no  case  to  exceed 
80  square  feet.  Walls  to  present  smooth  masonry  surface 
without  any  wood  trimming. 

Underwriters  having  jurisdiction  should  be  consulted  re- 
garding size  before  openings  are  made. 

Woodwork.  —  (a)  Core  to  be  made  of  well-seasoned  white 
pine  or  similar  non-resinous  wood.  Stock  to  be  of  a  good 
sound  quality,  practically  free  from  sap  and  large  or  loose  knots. 
Boards  to  be  plain  (not  beaded),  to  be  tongued  and  grooved, 
dressed  on  both  sides  and  not  to  exceed  8  inches  in  width.  Fin- 
ished thickness  of  boards  to  be  ^f  inch  full. 

(6)  Door  to  be  made  of  three  thicknesses  of  boards  dressed 
to  ^|  inch  (full),  the  outside  layers  to  be  vertical  and  the  inner 
layer  horizontal. 

(c)  Layers  to  be  securely  fastened  together  by  wrought- 
iron  clinch  nails  driven  in  flush  and  clinched  so  as  to  leave 
smooth  surfaces  on  both  sides  of  the  door.  Vertical  and  hori- 
zontal rows  of  nails  not  to  exceed  8  inches  apart,  placing  the 
outer  rows  near  the  edges  of  the  door. 

Tin  -Covering.  —  The  fire-resisting  value  of  a  wood  door 
encased  in  tin  depends  upon  the  exclusion  of  oxygen  from  the 
wood,  thereby  retarding  or  preventing  combustion,  and  also 
upon  the  degree  to  which  bulging  in  the  covering  can  be  pre- 
vented when  the  door  is  exposed  to  fire.  To  obtain  these  re- 
sults the  covering  must  be  so  applied  that  the  joints  between 
the  plates  will  remain  intact  and  provision  made  for  the  escape 
of  the  gases  generated  from  the  wood  core.  In  covering  the 
door  follow  carefully  every  specification  given. 

(See  National  Board  Rules  for  full  description  in  re  making 
of  woodwork  and  applying  tin.) 

(i)  When  the  covering  is  complete,  cut  a  hole  three  or 
r  inches  in  diameter  through  the  middle  plate  on  the  exposed 


468         FIRE   PREVENTION   AND   FIRE   PROTECTION 

side  of  the  door  but  not  through  the  wood  core.  Secure  the  tin 
around  this  opening  with  small  nails  and  thoroughly  paint  the 
wood  thus  exposed.  (See  Fig.  136.) 


FIG.   136.  —  Swing  Tin-covered  Door. 


Note.  —  The  hole  will  prevent  bulging  of  the  covering  and 
rupture  of  the  joints  by  permitting  the  escape  of  gases  generated 
from  the  wood  core  when  the  door  is  exposed  to  fire.  Care 
should  be  taken  to  ascertain  which  is  the  exposed  side  of  the  door 
before  the  hole  is  made.  Usually  the  hole  should  be  made 
after  the  door  is  mounted.  Three-inch  holes  should  be  made  for 
doors  under  fifty  square  feet  in  area  and  four-inch  holes  for  doors 
in  excess  of  fifty  square  feet. 

The  caution  concerning  the  proper  making  of  tin-covered 
shutters,  previously  given  on  page  428,  is  equally  applicable  to 
doors. 

Swing  Doors.  —  Swinging  fire  doors  to  shut  into  a  brick 
rabbet  in  wall,  rabbet  to  be  at  least  4  by  4  inches  and  to  have 
true  sides  and  angles  so  that  door  will  close  snugly  into  same,  or, 
door  to  shut  into  3-by  3-by  |-inch  angle-iron  rabbet  set  into  and 


FIRE-RESISTING   WINDOWS,    SHUTTERS   AND   DOORS      469 

secured  through  the  wall  by  lj-by  J-inch  iron  bars  spaced  not 
over  24  inches  apart.  Or,  door  to  shut  into  an  approved  door 
frame  of  iron. 

The  question  of  hardware  is  important.  Doors  in  excess  of 
7  feet  in  height  or  6  feet  in  width  must  have  3  hinges.  Hinges 
must  extend  three-fourths  the  width  of  door,  and  must  be  bolted 
through  from  side  to  side.  Doors  to  be  secured  by  at  least  3 
latches,  also  bolted  through,  and  so  arranged  as  to  be  easily 
operated  from  either  side  of  door. 

Swinging  tin-covered  doors  in  pairs  do  not  furnish  as  satisfac- 
tory protection  as  single  doors. 

Sliding  Doors.  —  Sliding  doors  to  overlap  sides  and  top 
of  opening  four  inches.  Top  of  door  to  conform  to  incline  of 
track,  f  inch  to  one  foot. 

Where  steel  lintels  are  used,  door  to  overlap  brickwork  four 
inches  above  upper  flange  of  I-beam  unless  such  lintels  are  pro- 
tected in  a  manner  satisfactory  to  Underwriters  having  jurisdic- 
tion. 

The  proper  hanging  of  sliding  doors  is  very  essential  to  secure 
efficiency,  so  much  so,  that  the  Underwriters'  Laboratories, 
Inc.,  have  made  many  tests  to  determine  which  types  and 
makes  are  acceptable.  Hardware  for  sliding  doors  especially 
should,  therefore,  preferably  be  selected  from  those  makes 
which  have  been  inspected  and  labeled  by  the  Underwriters' 
Laboratories,  Inc.,  as  being  in  accordance  with  the  requirements 
of  the  National  Board  of  Fire  Underwriters.  A  full  list  of 
such  makes  may  be  obtained  on  request.  Some  of  the  better 
known  manufacturers  of  fire-door  hardware  include  the  Geo.  T. 
McLauthlin  Company,  Boston,  the  Allith  Manufacturing  Com- 
pany and  the  Variety  Manufacturing  Company,  both  of  Chicago, 
the  Coburn  Trolley  Track  Manufacturing  Company,  Holyoke, 
Mass.,  and  the  McCabe  Hanger  Manufacturing  Company, 
New  York. 

Fire-resisting  Qualities.  —  The  tin-clad  fire  door  is  the  recog- 
nized standard  among  insurance  interests.  Like  the  tin-clad 
shutter,  it  is  probably  equal  to  the  best  low-priced  protection 
which  can  be  obtained,  but  other  types  are  certainly  as  efficient. 
Tin-clad  doors  are  not  infallible,  and  any  severe  exposure  will 
always  require  double  doors,  as  is  pointed  out  later. 

Fire  tests  of  tin-clad  doors  compared  with  other  types  are 
given  in  following  paragraphs. 


470         FIRE    PREVENTION    AND    FIRE    PROTECTION 

Advantages  and  Disadvantages.  —  Tin-covered  doors  are  cheap, 
generally  available,  made  according  to  standard  requirements, 
fire-resistive,  and  non-radiant.  On  the  other  hand,  they  are 
subject  to  deterioration,  especially  in  damp  locations,  and  sus- 
ceptible to  damage,  as  from  trucking,  opening  and  closing,  etc. 
Careful  maintenance  is  essential. 

Tin  and  Asbestos-clad  Doors.  —  Tests  of  what,  in  England, 
are  called  " armoured"  or  tin-clad  doors,  lined  also  with  asbestos 
board,  have  been  made  by  the  British  Fire  Prevention  Committee. 

"Red  Book"  No.  146  describes  a  test  made  May  24,  1909,  on 
such  a  3-ply  sliding  door,  7  feet  6  inches  wide  by  8  feet  3J  inches 
high,  overlapping  the  opening  6J  inches  at  the  top  and  3  inches 
on  either  side.  The  test  was  for  four  hours,  temperature  in- 
creasing to  1800°  F.,  followed  by  application  of  water  on  fire 
side  for  five  minutes,  with  a  view  to  fulfilling  the  requirements 
for  classification  "Full  protection"  class  B.  On  the  application 
of  water  the  upper  portion  of  door  collapsed.  Classification  was 
not  obtained.  The  following  "Note"  prefaced  this  report: 

The  test  reported  upon  in  the  following  pages  practically 
concludes  a  series  of  important  investigations  with  doors  known 
as  'armoured'  (i.e.,  tin-clad),  doors. 

Various  types  and  sizes  have  been  under  test,  and  the  series 
has  included  examples  where  linings  of  asbestos  board  have  been 
applied. 

Generally  speaking,  the  confidence  accorded  to  the  ordi- 
nary ' armoured7  door  by  those  concerned  in  fire  insurance 
matters  is  entirely  misplaced,  and  the  various  public  authori- 
ties who  have  refused  to  recognize  them  as  affording  any  high 
degree  of  fire-resistance  were  certainly  well  advised. 

If  well  made  and  well  fitted, . '  armoured '  doors  afford  what 
this  committee  describes  as  *  temporary'  or  'partial'  fire  pro- 
tection, but  they  do  not  afford  —  even  when  supplemented  with 
asbestos  linings  —  what  is  termed  'full  protection.' 

A  comparative  test  between  a  tin-  and  asbestos-clad  door  and 
a  plate-iron  door  is  given  under  heading  "Plate-iron  Doors." 

Copper-covered  Doors  are  often  used  on  roofs,  pent-houses, 
etc.,  where  continually  exposed  to  the  weather.  They  are  more 
expensive  than  tin-covered  doors,  but  their  maintenance  is  more 
satisfactory  for  outside  use.  If  the  copper  covering  is  lock- 
jointed  over  a  wood  core,  exactly  the  same  as  for  tin-covered 
doors,  they  will  generally  be  accepted  by  Underwriters  as  a 
substitute  for  the  latter  type,  although  inferior  from  the  stand- 
point of  fire-resistance. 


FIRE-RESISTING   WINDOWS,    SHUTTERS   AND    DOORS      471 

Plate-iron  Doors.  —  The  National  Board  Rules  cover  two 
types  of  iron  doors,  viz.,  the  "standard  sheet-iron  door,"  made 
of  No.  12  gauge  sheet-iron,  which  may  be  used  in  locations  where 
exposure  is  not  liable  to  be  severe,  but  which  is  not  recom- 
mended; and  the  standard  "  Vault  pattern,"  for  which  some  of 
the  principal  requirements  are  as  follows: 

Openings  not  to  exceed  50  square  feet  in  area.  Doors  for 
larger  openings  require  special  treatment. 

Door  Plates.  —  (a)  To  be  of  ^-inch  iron  or  steel  thoroughly 
straightened.  Single  plates  to  be  used  where  practicable. 

(6)  To  overlap  wall  frame  at  least  one  inch  on  all  sides; 
or  if  doors  are  flush,  to  shut  into  at  least  f-inch  rabbet  all  around, 
formed  by  angle  on  back  of  wall  frame. 

(c)  To  be  securely  riveted  to  the  panel  frame  and  panel 
bars. 

(d)  Where  two  plates  are  used  the  joint  to  be  reinforced 
by  3  by  jVmcn  strip  or  splice  plate  securely  riveted  to  each 
plate.     Rivets  on  splice  plate  to  be  staggered  and  not  to  exceed 
9  inches  apart  on  each  plate. 

Panel  Frame.  —  (a)  To  be  made  of  2-by  2-by  f-inch  angle 
iron,  continuous  with  bent  corners  or  with  corners  reinforced  by 
fillet  angles  where  joined.  Fillet  angles  to  be  securely  riveted 
in  place. 

(6)  To  be  stiffened  with  2-by  2-by  f-inch  angle-iron  panel 
bars  with  ends  off-set  so  as  to  extend  over  sides  of  frame,  or 
ends  may  be  fastened  with  fillet  angles. 

(c)  Each  frame  to  be   provided  with  at  least  two  panel 
bars,  and  where  doors  exceed  seven  (7)  feet  in  height  panel  bars 
not  to  exceed  two  feet  apart. 

(d)  To  be  placed  as  near  the  edges  of  the  door  plate  as 
practicable. 

Riveting.  —  Rivets  to  be  of  Norway  iron,  at  least  f  of  an 
inch  in  diameter  and  spaced  not  over  six  inches  apart.  Steel 
rivets  should  not  be  used. 

As  the  fire-resisting  qualities  of  the  iron  door  depends 
largely  on  proper  riveting,  the  rivets  should  be  properly  placed 
and  carefully  drawn  up. 

A  typical  plate-iron  door  is  shown  in  Fig.  150. 

Fire-resisting  Qualities.  —  "Red  Book"  No.  25,  of  the  British 
Fire  Prevention  Committee,  describes  a  comparative  fire  test, 
made  June  14,  1899,  between  a  tin-clad  and  a  plate-iron  door. 
The  test  was  for  one  hour,  temperature  gradually  increasing  to 
2000°  F.,  followed  by  application  of  cold  water  for  five  minutes. 
Each  opening  was  3  feet  9  inches  by  7  feet  6  inches.  The  tin- 
clad  door  was  2  inches  thick,  hung  to  fit  closely  against  the  face 
of  brick  wall,  with  3  inches  overlap  at  sides  and  top.  The  plate- 


472         FIRE    PREVENTION   AND    FIRE    PROTECTION 

iron  door  was  made  of  J-inch  plate,  reinforced  on  fire  side  by 
3-inch  by  J-inch  battens  along  all  edges,  across  the  middle,  and 
up  the  center,  thus  dividing  the  main  plate  into  four  panels. 

Summary  of  Effect.  —  The  wood  door  covered  with  tinned- 
steel  plates  remained  in  position,  but  was  much  buckled  and 
bulged,  and  the  upper  part  gradually  inclined  inwards  to  a  con- 
siderable extent,  permitting  the  passage  of  flame.  The  first 
spurt  of  flame  over  the  top  of  door  was  seen  after  five  minutes. 

The  iron-framed  and  panelled  door  remained  in  position, 
but  became  red  hot,  buckled  and  warped  considerably,  together 
with  its  rebated  frame.  The  upper  corner  on  the  lock  side 
gradually  inclined  inwards  to  a  considerable  extent,  permitting 
the  passage  of  flame.  The  first  spurt  of  flame  between  door  and 
frame  was  seen  after  twenty  minutes. 

Observations  After  Test. 

Tin-clad  Door.  —  All  the  woodwork  between  the  tinned- 
steel  plates  was  wholly  reduced  to  charcoal,  and  had  fallen  to 
pieces  within  the  steel  casing.  The  tin  was  melted  off  the  door. 
Some  of  the  plates  were  forced  out  of  position  and  the  welted 
edges  opened.  The  steel-plate  casing  was  considerably  bulged 
on  the  fire  side,  and  also  on  the  outside,  so  that  the  distance 
taken  at  the  center  between  the  inner  and  outer  casing  was 
9£  inches.  The  top  of  the  door  had  inclined  towards  the  fire 
side  to  the  extent  of  6  inches,  and  was  bent  1  inch  towards  the 
fire  side  at  the  bottom. 

Iron  Door.  —  The  iron-framed  and  panelled  door  had 
buckled  and  warped,  as  had  also  the  rebated  frame  in  which  it 
was  hung.  The  door  had  fallen  over  at  the  top  corner  on  the 
lock  side  to  the  extent  of  4|  inches.  The  rebated  frame  had 
bulged  to  the  extent  of  2|  inches  from  the  vertical  straight  line. 

"Red  Book"  No.  141  describes  a  second  comparative  test  made 
between  a  3-ply  tin-clad  door  hinged  to  built-in  pintles,  and 
J-inch  plate-iron  door  with  stiles  and  rails  3  inches  wide  on  both 
sides,  hung  in  an  angle-iron  frame.  The  test  was  of  a  tem- 
perature not  exceeding  4000°  F.  for  four  hours,  for  classification 
"Full  protection,"  class  B. 

The  tin-clad  door  allowed  both  fire  and  water  to  pass  through. 
The  maximum  reading  of  thermometer  hanging  in  front  of  door 
was  130°  F.  at  240  minutes.  Classification  was  not  obtained. 

The  iron  door  did  not  permit  the  passage  of  flame  through  the 
door,  or  between  the  door  and  frame.  The  door  became  a  bright 
red  heat,  the  outside  thermometer  registering  380°  F.  at  240 
minutes.  The  door  bulged  inwards  about  one  inch.  Classi- 
fication was  not  obtained. 


FIRE-RESISTING   WINDOWS,    SHUTTERS   AND   DOORS      473 

A  comparative  test  between  a  tin-  and  asbestos-clad  door  and 
a  plate-iron  door  is  described  in  "Red  Book"  No.  147.  The  test 
was  made  May  24,  1909,  duration  four  houis,  temperature  in- 
creasing to  1800°  F.,  followed  by  application  of  water  for  five 
minutes  on  fire  side.  The  openings  measured  3  feet  3  inches 
by  6  feet  9  inches.  The  " armoured"  door  was  2-ply,  hinged  to 
built-in  pintles,  overlapping  the  opening  3  inches  at  the  top  and 
4  inches  at  either  side.  The  plate-iron  door  was  made  of  a 
i-inch  steel  plate,  reinforced  by  4-by  J-inch  battens  on  both 
sides,  around  all  edges  and  across  the  center,  and  was  hung  in 
an  angle-iron  frame. 

The  maximum  readings  of  the  hanging  thermometers  in  front 
of  the  doors  were,  at  240  minutes,  180°  F.  for  the  armoured  door, 
and  375°  F.  for  the  plate-iron  door.  The  former  door  allowed 
both  fire  and  water  to  pass  through.  The  latter  door  did  not 
allow  the  passage  of  flame  through  the  door  or  between  the  door 
and  frame.  Classification  "Full  protection,"  class  B,  was  not 
obtained  in  either  case.  The  introductory  note  to  this  report 
is  as  follows: 

It  may  be  noted  that  the  radiation  of  heat  through  the  iron 
door  is  considerably  greater  than  through  the  asbestos-lined 
'armoured'  door,  yet  towards  the  conclusion  of  the  tests  the 
fire  came  over  the  top  of  the  latter. 

It  may  also  be  noted  that  the  iron  door  is  the  type  of  door 
now  required  under  the  London  Building  Act,  further,  that  the 
'armoured'  door  in  this  case  had  one  thickness  of  boarding  less 
than  required  by  the  British  Insurance  Companies,  whilst  the 
asbestos  lining  (two  thicknesses)  was  in  excess  of  their  require- 
ments. 

A  comparative  test  (made  July  25,  1900)  on  two  plate-iron 
doors,  practically  identical  except  that  one  had  stiles  and  rails 
on  one  side  only,  and  the  other  on  both  sides,  is  described  in 
"Red  Book"  No.  60.  Each  door  was  3  feet  3  inches  by  6  feet 
9  inches  in  size,  made  of  |-inch  steel  plate,  reinforced  with  ]-inch 
stiles  and  rails,  hung  in  an  angle-iron  frame.  The  double- 
battened  door  made  somewhat  the  better  showing. 

Advantages  .and  Disadvantages.  —  The  foregoing  tests  show 
conclusively  that,  as  far  as  fire-resistance  ij  concerned,  plate- 
iron  doors  are  superior  to  tin-clad  doors,  but  the  radiation  of 
heat  permitted  by  plate-iron  construction  —  375  degrees  in  one 
test  as  compared  with  180  degrees  for  the  tin-clad  door  —  con- 
stitutes a  most  serious  objection.  Plate-iron  doois  may  be 


474         FIRE    PREVENTION    AND    FIRE    PROTECTION 

made  of  better  appearance  than  tin-covered,  but  at  considerably 
greater  cost. 

"Composite"  Doors,  i.e.,  sheet-  or  plate-iron  doors  filled 
with  asbestos  or  other  fire-resisting  material,  have  been  investi- 
gated by  the  British  Fire  Prevention  Committee  through  a  series 
of  valuable  tests,  which  may  be  briefly  summarized  as  follows: 

"Red  Book"  No.  117. —Test  of  two  " Ferro-asbestic "  doors, 
made  October  3,  1906.  Test  for  "Full  Piotection,"  class  A, 
150  minutes  duration,  temperature  not  exceeding  2000°  F.,  water 
applied  2  minutes  on  fire  side.  Doors  3  feefc  10  inches  by  7  feet 
7  inches,  If  inches  thick  at  stiles  and  rails,  and  f-inch  thick  in 
panels,  made  of  channel-iron  frame  and  sheet -iron,  one  door 
panelled  and  moulded  on  both  sides,  the  other  having  faces  with 
vertical  indentations  similar  to  V-shaped  boarding.  Each  hinged 
to  an  angle-iron  frame. 

Door  No.  1.  The  panels  bulged  after  5  minutes,  flame 
pa3se:l  between  door  and  frame  at  120  minutes. 

Door  No.  2.  Door  and  frame  buckled  after  10  minutes, 
flame  passed  between  door  and  frame  at  30  minutes. 

Neither  door  received  the  classification  sought.  These  par- 
ticular doors  are  capable  of  improvement,  but  even  as  they  stand 
they  have  shown  up  under  test  as  well  as  many  other  doors 
which  are  dubbed  with  the  title  ' fireproof.' 

"  Red  Book"  No.  141.  —  Test  of  two  composite  doors,  made  Feb- 
ruary 24,  1909.  Test  for  "Full  protection,"  class  B,  4  hours, 
2000°  F.,  water  for  5  minutes.  Doors  2  feet  9  inches  by  6  feet 
5  inches,  made  of  iron  and  asbestos  composition  filled.  One 
door  hinged  in  angle-iron  frame,  the  other  in  brick  rebate. 
Classification  was  not  obtained  for  either. 

"Red  Book"  No.  149. — Test  of  two  large  ferro-asbestic  or 
"Dreadnought"  doors,  made  January  12,  1910,  for  classification 
"Full  protection,"  class  B,  for  door  No.  1,  and  "Full  Protec- 
tion" class  A,  for  door  No.  2  (compare  page  116). 

Door  No.  1  was  7  feet  by  8  feet  opening,  1J  inches  thick,  made 
of  sheets  of  No.  19  gauge  steel  with  hydraulically  stamped  panels, 
with  inner  and  outer  frames  of  channel-iron,  and  with  filling  of 
asbestos  and  kieselguhr.  This  door  was  hung  to  an  overhead 
track. 

Door  No.  2  was  7  feet  by  7  feet  6  inches  opening,  sliding  on 
bottom  runners,  the  construction  of  door  being  the  same  as  No.  1 


FIRE-RESISTING    WINDOWS,    SHUTTERS   AND    DOORS      475 

except  that  it  had  vertical  V-shaped  grooves  on  surface  instead 
of  panels. 

Summary  of  Test.  —  Door  No.  1..  After  170  minutes,  a 
maximum  oulge  of  2|  inches  was  recorded.  On  the  application 
of  water  at  240  minutes  the  force  of  the  stream  broke  down  the 
inner  steel  casing  and  washed ,  out  the  interior  composition, 
causing  the  outer  steel  covering  to  bulge  outwards.  Fire  did 
not  pass  through.  Classification  "Full  protection,"  class  B, 
was  obtained. 

Door  No.  2.  At  130  minutes  a  maximum  bulge  of  3j 
inches  was  recorded.  At  110  minutes  flame  passed  through, 
owing  to  the  pulling  away  from  brickwork  of  one  side  of  channel 
frame.  Classification  not  given. 

Introductory  Note.  —  This  report  continues  the  investiga- 
tion with  doors  of  a  composite  type.  The  former  (see  "  Red 
Book"  No.  117,  quoted  above)  Was  a  test  with  comparatively 
small  doors  of  a  similar  character.  This  one  is  with  large  doors, 
and  the  satisfactory  results  of  the  test  demonstrate  that  this 
type  of  door,  if  properly  hung,  may  be  considered  ' fire-resisting.' 
The  great  advantage  of  a  door  of  this  type  from  the  fire-protec- 
tion point  of  view  is  the  small  amount  of  heat  radiated  through 
it.  In  former  tests  with  'all-iron'  doors,  it  was  found  that 
although  the  doors  resisted  the  passage  of  fire,  the  radiation  of 
heat  through  them  was  sufficient  (unless  double  doors  were  used) 
to  ignite  combustible  material  in  close  proximity  on  the  side 
opposite  to  the  fire,  and  in  doors  of  the  'Armoured'  or  tin-clad 
type,  the  doors  failed  by  reason  of  the  interior  being  consumed 
and  letting  the  fire  round  or  over  them  before  the  conclusion 
of  the  test. 

One  of  the  doors  in  this  report  failed  by  reason  that  the 
channel  into  which  the  door  closed  was  insufficiently  secured  to 
the  brickwork. 

The  "Ajax"  Fire  Door,  manufactured  by  the  Kinnear  Manu- 
facturing Company,  is  a  composite  door  2J  inches  thick,  made  of 
horizontal  sections  of  No.  26  gauge  interlocking  galvanized-steel, 
8  inches'  wide,  assembled  on  an  interior  skeleton  framework 
made  of  fVinch  bars  and  angles.  The  sections  of  sheet  steel 
are  tongued  and  grooved  at  the  intersections.  Vertical  rods, 
\  inch  diameter,  and  18  inches  centers,  pass  through  the  interior, 
which  is  filled  with  mineral  fiber. 

This  type,  shown  in  Fig.  137,  is  approved  by  the  Underwriters* 
Laboratories,  Incorporated,  as  a  standard  door  for  openings  not 
exceeding  80  square  feet  in  area.  Automatic  closing  device 
may  be  attached  if  desired.  Double  doors  are  required  at  fire- 
wall openings. 


476         FIRE    PREVENTION    AND    FIRE    PROTECTION 


FIG.   137.  —  "Ajax"  Fire  Door. 


Corrugated-iron  Doors,  as  made  by  the  Saino  Fire  Door 
and  Shutter  Company,  of  Memphis,  Tenn.,  are  accepted  by  the 
Underwriters'  Laboratories,  Incorporated,  as  the  equivalent  of 
the  standard  2^-inch  fire  door,  for  openings  not  exceeding  6  feet 
in  width.  These  doors  are  made  of  No.  22  gauge  galvanized 
corrugated-iron,  with  a  jo-inch  sheet  of  asbestos  between.  The 
face  of  door  is  made  of  a  single  sheet  of  the  corrugated-iron  with 
the  corrugations  running  vertically.  To  provide  for  expansion 
and  contraction,  the  rear  side  of  door  is  made  of  several  sections 
of  the  corrugated -iron  (with  corrugations  running  horizontally), 
fastened  together  loosely  by  means  of  bolts  in  slotted  holes.  The 
stiffening  frame  is  also  sectional,  corresponding  to  the  number 
of  sections  in  the  rear  wall.  These  doors  weigh  less  than  the 
standard  tin-clad  door,  the  cost  being  about  the  same. 

Fig.  138  shows  a  Saino  fire  door  after  a  severe  two-hour  fire 
test  in  a  building  at  Knoxville,  Tenn. 

Steel  Rolling  Fire  Doors,  when  single,  are  approved  by  the 
Underwriters'  Laboratories,  Inc.,  for  use  as  stair  or  elevator 


FIRE-RESISTING    WINDOWS,    SHUTTERS   AND    DOORS      477 


FIG.   138.  —Fire  Test  of  "Saino"  Fire  Door. 

doors  when  made  automatic  in  action,  and  in  shafts  which 
do  not  communicate  with  more  than  one  fire  section,  provided 
openings  do  not  exceed  8  feet  in  width  and  9  feet  in  height, 
doors  to  be  mounted  on  face  of  wall.  Approved  doors  of  this 
type  comprise  "  Variety  No.  33,"  made  by  the  Variety  Manu- 
facturing Company,  Chicago,  "Abacus  No.  1,"  made  by  the 
Kinnear  Manufacturing  Company,  Columbus,  Ohio,  and  "Wil- 
eon  Arrangement  No.  1,"  made  by  J.  G.  Wilson  Manufacturing 
Company,  New  York. 


478 


FIRE    PREVENTION    AND    FIRE    PROTECTION 


The  latter  door  is  illustrated  in  elevation,  section  and  plan 
in  Fig.  139,  while  Fig.  140  shows  a  detail  of  the  hood  and  coil,  etc., 
when  the  door  is  closed.  The  main  constructional  points  of  this 
type  may  be  briefly  described  as  follows: 


Line  of  Hood- 
FIG.   139.  —  "Wilson  Arrangement  No.  1"  Steel  Rolling  Door. 

1.  General  Design  and  Construction.  —  Single  door,  spring 
counterbalanced,  for  openings  in  stair  and  elevator  shafts  not 
exceeding  8  feet  wide  by  9  feet  high.     Mounted  on  the  face  of 
the  wall,  overlapping  at  the  sides  and  top.     Manually  operated 
by  handle  placed  on  bottom  bar  of  curtain.     Automatically 
closed  by  a  releasing  device  actuated  by  a  fusible  link.     Pro- 
vided with  internal  baffle  plates  closing  the  space  between  the 
curtain  and  hood  on  both  sides. 

2.  Curtain.  —  Made  of  interlocking  slats  formed  of  No.  20 
U.  S.  gauge  galvanized  open-hearth  steel.     Finished  slats  ap- 
proximately 2J  inches  wide,  center  to  center,  slipped  together 
and  provided  with  special  malleable-iron   castings   on   side   of 
each  slat.     Curtain  to  extend  into  the  grooves  If  inches  for 


FIRE-RESISTING    WINDOWS,    SHUTTERS   AND    DOORS      479 


openings  6  feet  in  width  and  less,  and  two  inches  for  openings 
6  to  8  feet  in  width. 

The  upper  slat  of  curtains  to  be  reinforced  by  two  1  by  f 
inch  iron  strips  riveted  together  by  J-inch  rivets  spaced  not  to 
exceed  12  inches  apart  and  attached  to  the  barrel  or  rings  by 
^j-inch  stove  bolts  with  washers  on  outside.  Bolt  holes  slotted 
and  bolts  spaced  not  exceeding  18  inches  apart.  Bottom  of 
the  curtain  to  be  fitted  with  a  bar. 

3.  End  Locks.  —  Each  end  of  each  slat  to  be  provided  with 
a  special  malleable  iron  casting  on  one  side  riveted  through  the 
slat  by  two  J-inch  rivets.     Cast- 
ings are  designed  to  hold  the  I 

slats  in  place,  to  take  the  wear 
in  the  grooves,  to  keep  the  joints 
between  the  slats  in  close  con-  ( 
tact,  to  stiffen  the  shutter  verti- 
cally and  to  act  as  fire  stop  at  I 
the  end  of  the  slats. 

4.  Bottom  Bar.  —  Made  of 
two  H  by  H  by  T3^-inch  angles 
and  4  by  ^  inch  plate  riveted  or 
bolted  together  through  slotted  I 
holes,  spaced   not   to   exceed   9 


inches  apart.  Bolts  or  rivets 
inch  in  diameter  and  provided 
with  steel  and  vulcanized  wood- 
fiber  washers.  Plate  to  be 
riveted  or  bolted  to  the  lower 
slat  at  not  to  exceed  9-inch  in- 
tervals. Bars  to  be  provided 
with  an  angle  clip  at  each  side 
at  the  center. 

The    bottom    is    also    pro- 
vided with  self-locking  side  bolts 


Hood 


SECTION  THROUGH 
SIDE  GROOVES 


FIG.  140.  —  Detail  of  Hood  and  Coil, 
"Wilson  Arrangement  No.  1." 

at  each  end  that  can  be  unfastened  from  either  side. 

5.  Barrel.  —  Made  of  2-,  3-  or  4 -inch  commercial  steel  pipe, 
depending  on  the  width  of  the   curtain.     The  barrel  is  sup- 
ported at  each  end  by  means  of  short  sections  of  1  J-inch  shafts 
rigidly  secured  to  the  iron  brackets  and  projecting  into  the  ends 
of  barrel  through  cast-iron  bushings  provided  with  babbitted 
bearings.     Ball  bearings  may  be  substituted  for  the  babbitted 
bearings  specified.     Within  the  shaft  is%  placed  a  helical  steel 
spring,  of  such  size   and  length  as  properly  to  counterbalance 
the  shutter  and  make  it  operative.     One  end  of  spring  is  fas- 
tened to  inner  surface  of  barrel,  and  the  other  end  to  the  fixed 
steel  shaft  carrying  one  end  of  the  barrel.     Where  rings  are 
used  on  barrel,  they  are  to  be  spaced  2  to  3  feet  apart,  secured 
to  the  barrel  by  two  f-inch  pins  or  set  screws. 

6.  Brackets.  —  Made  of  cast-iron  of  a  pattern  suitable  for 
the  support  of  the  barrel,  coil  and  hood,  and  to  close  the  open- 
ings at  the  ends  of  the  hood  when  the  parts  are  in  place.     Each 


480         FIRE    PREVENTION    AND    FIRE    PROTECTION 

bracket  provided  with  three  ^-inch  holes  for  bolting  to  the 
wall. 

7.  Hoods.  —  Made  of  at  least  No.  24  U.  S.  gauge  galvanized- 
iron  formed  to  fit  the  brackets  and  attached  by  J-inch  machine 
screws  or  bolts  spaced  not  to  exceed  6  inches  apart  and  with 
washers  under  heads.     The  edges  are  stiffened  by  a  2  by  2  by  f 
inch  angle  at  the  bottom  and  a  2  by  2  by  J  inch  angle  at  the  top, 
riveted  in  place  by  J-inch  rivets  spaced  not  to  exceed  9  inches. 
Ends  of  angles  rest  on  lugs  cast  on  brackets  and  fastened  through 
slotted  holes  by  f-inch  bolts. 

8.  Baffle  Plates.  —  The  curtain  is  provided  with  continuous 
baffle  plates  on  each  side,  attached  by  hinges  spaced  not  to 
exceed  12  inches  apart.     Projections  at  each  end  engage  guide 
strips  which  force  baffle  plates  against  wall  and  against  angle 
at  lower  edge  of  hood,  when  the  door  is  completely  closed. 
Guide  strips  are  bolted  to  the  upper  end  of  grooves  which  extend 
into  the  hood.     See  Fig.  140. 

9.  Grooves.  —  Made  of  two  steel  plates  3J  by  T%  inches, 
riveted  together  through  a  continuous  separator  made  of  one 
channel  or  of  two  angles  of  -j\-inch  steel,  about  1  by  1  inch. 
Holes  for  rivets  are  slotted.     Groove  is  secured  to  the  wall  by 
means  of  f-inch  angle  riveted  to  the  groove  proper.     Rivet  and 
bolt  holes  are  slotted.     Fiber  packing  is  used  under  iron  washers 
in  the  case  of  all  slotted  holes.     Upper  wall  bolt  is  not  more 
than  6  inches  from  end  of  groove,  and  bolts  are  spaced  not  more 
than  18  inches  apart.     Lower  bolt  not  more  than  3  inches  from 
end  of  groove. 

Steel  rolling  doors  may  be  placed  with  the  hood  and  coil,  etc., 
within  the  wall  reveal  of  elevator  openings.  The  ' '  Abacus  No.  2  " 
door  manufactured  by  the  Kinnear  Manufacturing  Company 
may  be  so  used  for  openings  not  exceeding  8  feet  in  width  and 
9  feet  in  height  in  standard  elevator  shafts  which  do  or  do  not 
communicate  with  more  than  one  fire  section.  This  door  is 
manually  operated  by  a  handle  at  bottom  of  curtain,  and  is 
automatically  closed  by  a  releasing  device  which  is  actuated  by 
two  fusible  links  which  operate  at  an  approximate  temperature 
of  160  degrees. 

Fire-resisting  Qualities.  —  A  considerable  number  of  fire  and 
water  tests  of  steel  rolling  doors  have  been  made  by  the  British 
Fire  Prevention  Committee,  among  which  may  be  mentioned 
the  following: 

Red  Book  No.  144  describes  test  of  a  single  steel  rolling  door 
of  the  "Wilson"  type.  The  size  of  opening  was  7  feet  wide  by 
8  feet  high.  The  object  of  test  was  to  record  the  effect  of  a 
fire  of  2 §  hours'  duration  at  a  temperature  gradually  increasing 


FIRE-RESISTING    WINDOWS,    SHUTTERS   AND    DOORS      481 

to  1800°  F.,  followed  by  the  application  of  water  for  two  minutes 
on  the  fire  side,  with  a  view  to  being  classified  as  affording  "Full 
protection/'  class  A.  The  summary  of  test  was  as  follows: 

After  48  minutes  the  paper  attached  to  the  north  wood 
post  (12  inches  away  from  face  of  shutter)  caught  fire.  After 
66  minutes  the  paper  attached  to  the  south  wood  post  caught 
fire.  At  the  conclusion  of  2^  hours  the  wooden  blocks  were 
consumed.  Flame  passed  between  the  shutter  and  the  groove 
on  the  north  side  after  85  minutes.  The  shutter,  grooves  and 
gear  remained  in  position  and  were  slightly  damaged.  The 
maximum  bulge  of  the  shutter  was  3  inches  when  examined  two 
days  after  test.  The  shutter  could  not  be  worked  or  raised 
after  the  test.  Classification  'Full  protection/  class  A,  was  not 
obtained. 

Kalamine  Doors.  —  The  rough,  unfinished  appearance  of 
the  standard  tin-clad  door  led  to  attempts  fco  provide  a  more 
architectural  product  for  use  in  the  interiors  of  buildings  where 
appearance  has  to  be  considered.  One  result  was  the  kalamine 
method,  which,  while  producing  work  of  superior  finish,  does  not, 
however,  equal  the  tin-clad  construction  in  efficiency  under 
fire  test.  Hence  kalamine  doors  are  generally  limited  to  interior 
corridors  and  partitions,  and  to  stair  and  elevator  openings. 
They  are  quite  extensively  used  in  office  and  public  buildings, 
hotels  and  the  like.  Kalamine  doors  are  not  approved  by 
Underwriters  for  use  in  openings  in  fire  walls. 

Among  the  better  known  manufacturers  of  kalamine  work 
whose  doors  are  inspected  and  labeled  by  the  Underwriters' 
Laboratories,  Inc.,  are  the  Thorp  Fireproof  Door  Company  of 
Minneapolis,  and  the  United  States  Metal  Products  Com- 
pany, New  York  City.  The  " Richardson"  seamless  doors, 
made  by  the  former  company,  are  among  the  oldest  and  best  of 
this  type  on  the  market.  These  are  made  of  a  3-ply  built-up, 
cross-construction  pine  core,  covered  with  asbestos  paper,  and 
enclosed  with  sheet-metal,  —  either  steel,  which  may  be  painted, 
grained  to  match  wood  trim,  or  electro-plated  with  copper, 
brass  or  bronze,  —  or  with  solid  sheet  copper,  brass  or  bronze. 

For  doors  up  to  3  feet  4  inches  wide  and  8  feet  hi^h,  each  side  is 
made  of  one  continuous  sheet  of  metal,  with  hydraulically  pressed 
panels  made  therein  without  joints  or  seams.  These  face  sheets 
overlap  in  a  groove  on  all  edges  of  the  door,  being  held  in  place 
by  a  continuous  band  inserted  in  the  groove,  through  which  are 
placed  screws  which  pass  through  the  edges  of  both  face  plates. 


482 


FIRE    PREVENTION    AND    FIRE    PROTECTION 


Fig.  141  illustrates  the  construction,  and  also  a  typical  door  jamb 
and  casing  of  kalamine  work.  The  standard  thickness  of  door 
is  2|  inches. 


FIG.   141.  —  "Richardson"  Kalamine  Door. 

When  doors  wider  than  3  feet  4  inches  are  required,  each  face 
is  made  in  two  sheets  which  are  locked  together  with  a  flush 
double  lock-joint  at  a  central  stile,  as  shown  in  Fig.  142,  thus 
giving  a  double  row  of  panels. 


FIG.  142.  —  Lock-jointed  Central  Stile,  "Richardson"  Door. 

Kalamine  doors  are  also  made  to  receive  plate-  or  wire-glass 
panels;  and  corridor  windows  and  trim  of  kalamine  work  are 
frequently  used  throughout  entire  buildings. 

Although  standard  panel  sizes,  mouldings,  etc.,  are  usually 
employed,  special  details  may  be  executed  in  kalamine  work  at 
increased  cost.  All  hardware,  if  furnished,  is  fitted  to  the  doors, 
etc.,  at  the  factory,  without  extra  charge. 

Fire-resisting  Qualities.  —  The  behavior  of  kalamine  interior 
doors  and  trim  in  the  Kohl  Building  in  the  San  Francisco  fire  has 
previously  been  referred  to  on  page  423.  There  was  sufficient 
evidence  to  show  that  the  doors  and  trim  both  retarded  and  con- 
fined the  fire,  frequently  to  such  an  extent  as  to  confine  the 


FIRE-RESISTING   WINDOWS,    SHUTTERS   AND    DOORS      483 


flames  to  rooms  where  the  fire  was  communicated  through  win- 
dows. A  great  mistake,  however,  was  in  the  use  of  plate-  instead 
of  wire  glass  in  the  doors. 

Metallic  Doors.  —  Hollow  sheet-metal  doors,  when  expertly 
made,  undoubtedly  constitute  the  most  efficient  well-appearing 
door  construction  which  has  yet  been  devised.  Like  kalamine 
doors,  they  are  not  approved  by  the  Underwriters'  Labora- 
tories, Inc.,  or  by  other  insurance  authorities  for  use  in  fire 
walls  where  severe  exposure  is  to  be  expected;  but  for  corridor, 
partition,  stair  or  elevator  doors,  no  more  satisfactory  type 
possessing  a  high  degree  of  finish  can  be  selected,  and  many  of 
the  finest  examples  of  thoroughly  fire-resisting  buildings  are 
being  equipped  with  this  style  of  doors  and  trim. 

Among  the  best  known  manufacturers  of  this  type  are  the 
Dahlstrom  Metallic  Door  Company  and  the  Art  Metal  Con- 
struction Company,  both  of  Jamestown,  N.  Y.,  and  the  United 
States  Metal  Products  Company,  N.  Y. 


Steel  Strap 
^—  Air  Chambers 


Wood  Buck 
Air  Chamber 
Asbestos         Compressed 
Uumg  Joint      Cork 


Angle-Iron  Frame 
Construction 


Joint 
X  Hinge  Bar 


Felt  Lining         / 
Lock  Strip 


Wood  Buck 
Construction 


FIG.    143.  —  "Dahlstrom"  Metallic  Door. 

The  Dahlstrom  doors  are  made  from  two  No.  20  gauge  steel 
plates,  one  complete  side  stile  and  one  panel  face  being  formed 
from  each  sheet.  These  two  halves  are  then  connected  together 
by  means  of  interlocking  seams  on  opposite  sides  of  the  door  and 
panel.  See  points  marked  " Joint"  in  Fig.  143.  The  panels 
are  lined  with  a  sheet  of  asbestos  next  to  the  steel  on  each  side, 
the  center  space  being  filled  with  a  layer  of  hair-felt  paper,  mak- 
ing a  resilient  and  non-heat-conducting  filling.  The  stiles  are 
left  hollow  with  the  exception  of  strips  of  cork  running  through 
the  center  of  each,  these  being  for  the  purpose  of  deadening  the 
metallic  ring.  The  Danel  is  then  completed  by  planting  on  and 
welding  properly  formed  cross  rails  at  the  top  and  bottom,  or 
if  more  than  one  panel  is  desired,  they  are  formed  by  planting 


484         FIRE   PREVENTION   AND   FIRE   PROTECTION 

on  intermediate  rails,  which  are  coped  over  the  moulded  side 
stiles.  The  top  and  bottom  edges  are  then  reinforced  with 
channels  and  bars,  making  the  doors  perfectly  straight,  and 
very  rigid.  The  fire-resisting  qualities  of  thess  doors  are  greatly 
augmented  by  the  fact  that  no  rivets  or  screws  are  allowed  to 
pass  through  from  one  side  to  the  other,  thus  avoiding  the  trans- 


FIG.  144.  —  "  Dahlstrom"  Elevator  Doors,  Forest  Chambers  Apartments,  N.  Y. 

mission  of  heat.  Especial  provision  must  be  made,  in  making 
the  doors,  for  the  attachment  of  all  hardware,  and  for  reinforce- 
ment at  such  points. 

The  doors  are  then  sent  to  the  finishing  department  where 
the  steel  is  thoroughly  cleaned  from  all  rust,  grease  or  other 
impurities  before  the  enamel  coating  is  put  on.  They  are  then 
treated  from  6  to  8  times,  each  coat  being  baked  in  large  ovens. 
After  the  final  coat  of  varnish  is  put  on,  the  doors  are  usually 
rubbed  to  an  egg-shell-gloss  finish,  equal  in  quality  to  any  hard- 


FIRE-RESISTING    WINDOWS,    SHUTTERS   AND    DOORS      485 

wood  finish,  and  more  durable  on  account  of  being  baked  on. 
Any  wood,  such  as  quartered  oak,  Circassian  walnut,  etc.,  may 
be  faithfully  imitated.  The  corridor  and  partition  doors  and 
trim,  etc.,  in  the  new  Singer  Building  and  tower  in  New  York 


FIG.  145.  —  "Dahlstrom"  Elevator  Doors,  Forest  Chambers  Apartments,  N.  Y. 

City,  are  of  the  Dahlstrom  metallic  type.  Fig.  143  gives  a 
section  through  a  typical  door,  with  four  different  styles  of 
casings  (for  trim,  etc.,  see  later  paragraph).  Fig.  144  illustrates 
the  Dahlstrom  combination  slidejand-swing  elevator  doors,  as 
used  in  the  Forest  Chambers  Apartments,  Broadway  and  113th 


486         FIRE    PREVENTION    AND    FIRE    PROTECTION 

St.)  New  York  City,  G.  and  E.  Blum,  architects.  The  same 
doors  are  shown  in  more  detail  in  Fig.  145.  They  are  finished 
in  Circassian  walnut.  The  transom  bar  shown  over  the  doors 
is  attached  to  the  swing  door,  on  the  back  of  which  are  a  track 
and  hangers  for  the  sliding  door.  When  it  is  desired  to  use  the 
full  width  of  the  opening,  the  sliding  door  is  opened,  then,  by 
opening  flush  bolts  at  the  bottom  of  the  swing  door  and  in  the 
end  of  the  transom  bar,  the  swing  door  and  sliding  door  may  be 
swung  open  together. 

Standard  metallic  doors,  approved  by  underwriters  for  uses 
above  mentioned,  vary  in  thickness  from  1J  to  2|  inches. 

For  hospitals,  metallic  doors  are  especially  sanitary  on  account 
of  the  non-absorbent  qualities  of  the  baked  enamel  finish.  They 
are  easily  cleaned,  and  may  be  made  still  more  so  by  eliminating 
all  mouldings,  making  them  perfectly  flat,  or  with  smooth  de- 
pressions for  panels. 

Automatically  Closing  Doors.. —  Automatic  steel  rolling 
doors  have  been  described  in  a  previous  paragraph.  The 
following  rules  of  the  National  Board  of  Fire  Underwriters  cover 
sliding  and  swing  automatic  doors: 

Automatic  Sliding  Doors.  —  (a)  To  be  specified  by  the 
Underwriters  having  jurisdiction.  To  be  operated  by  at  least 
one  link  placed  above  the  door  and  near  but  not  in  contact  with 
the  ceiling.  Where  desired,  the  door  may  also  be  arranged  to 
close  by  the  fusing  of  an  additional  link  placed  near  the  top 
of  the  door  opening.  Fusible  links  to  fuse  between  160  and 
165°  F. 

(b)  The  fusible  link  to  be  so  arranged  that  when  it  gives 
way  under  heat  a  sufficient  excess  in  weight  will  be  exerted  to 
pull  and  latch  the  door  closed. 

(c)  The  cord  on  the  latch  side  to  be  of  flexible  phosphor 
bronze,  securely  attached  to  the  door.     The  cord  to  which  the 
link  is  attached  may  be  of  the  usual  form  if  desired. 

(d)  The  cord  sheaves  to  be  securely  fastened  to  the  wall 
with  expansion  bolts,  to  be  provided  with  bronze  bearings,  and 
so  constructed  that  the  cord  cannot  jump  the  groove. 

(e)  The  weight  on  the  side  toward  which  the  door  closes 
to  be  inclosed  in  a  suitable  box  to  prevent  molestation. 

(/)  Latch  to  be  provided  with  a  suitable  coiled  spring  for 
holding  it  in  place  and  to  insure  fastening. 

Automatic  Swinging  Doors  require  a  different  arrange- 
ment of  the  link  and  weights  closing  the  doors.  Weights  1o  be 
properly  boxed  and  placed  between  doors.  Cords  to  pass 
through  holes  drilled  in  wall 'frame  and  to  be  so  arranged  in 
sheaves  that  the  fusing  of  the  link  will  release  sufficient  weight 


FIRE-RESISTING   WINDOWS,    SHUTTERS   AND   DOORS      487 

to  pull  and  latch  the  door  closed.  Fusible  links  to  be  placed 
near  the  ceiling  and  arranged  so  that  the  fusing  of  the  link  on 
either  side  of  the  wall  will  operate  both  doors.  Several  links 
may  be  placed  on  either  side  if  desired.  The  cords  closing 
doors  should  be  sufficiently  weighted  to  keep  them  taut  when 
the  doors  are  opened  and  closed. 

Automatic  Swinging  Doors  in  Pairs.  —  To  be  so  arranged 
that  the  right-hand  doors  will  fold  over  left-hand  doors.  This 
requires  an  automatic  stop  or  trigger  at  the  top  of  the  doors 
which  will  hold  the  right-hand  door  sufficiently  open  to  allow 
the  left-hand  door  to  close  first.  The  closing  of  the  left-hand 
door  releases  the  trigger  and  allows  the  remaining  door  to  close. 
The  left-hand  door  to  be  provided  with  spring  bolts  or  latches 
at  both  top  and  bottom.  These  to  be  operated  from  either  side 
of  the  door  by  proper  handles  at  the  center."  * 


FIG.   146.  —  Automatic  Vertical  Fire  Doors. 


Automatic  Vertical  Doors.  —  Under  special  conditions, 
where  swinging  or  horizontally  sliding  doors  cannot  be  used, 
an  automatic  vertical  door  may  be  arranged  as  shown  in  Fig.  146. 
The  construction  of  the  door  proper  should  be  the  same  as  that 
of  other  fire  doors,  but  special  hardware  is  necessary. 


488         FIRE    PREVENTION   AND    FIRE   PROTECTION 

The  cord  connecting  with  fusible  links  is  attached  to 
lower  part  of  door  passing  over  its  proper  pulley  to  the  left  and 
supporting  the  smaller  weight.  Cord  to  be  provided  with  a 
fusible  link  at  the  bottom  of  the  door  and  also  one  near  the 
ceiling  when  the  door  is  open.  The  heavier  weight  is  perma- 
nently connected  by  a  wire  cable  to  the  upper  loop  at  top  of 
door,  and  is  adjusted  to  prevent  the  sudden  dropping  ®f  the 
door,  but  allowing  it  to  close  when  link  fuses. 

Automatic  Horizontal  Trolley  Fire  Door.  —  In  some  loca- 
tions where,  on  account  of  low  ceilings  or  obstructions  on  both 
sides  of  the  opening,  neither  a  swing,  sliding  nor  vertical  door  can 
be  used,  a  door  may  be  arranged  to  hang  on  sheaves  or  trolleys 
which  run  on  tracks  suspended  at  right  angles  to  the  wall.  Thus, 
when  open,  the  door  is  parallel  to  and  any  reasonable  distance 
away  from  the  wall.  When  installed  for  fire  protection,  a  fusible- 
link  automatic  closing  device  should  be  used.  This  system 
should  never  be  used  unless  absolutely  necessary,  and  then  only 
with  permission  of  Underwriters. 

Fusible  Links  of  the  approved  "Voigtmann"  type,  as  used 
for  automatic  closing  devices  in  connection  with  doors  and  win- 
dows, are  illustrated  at  full  size  in  Fig.  147.  The  link  consists 


FIG.   147.  —  "Voigtmann"  Fusible  Links. 

of  two  pieces  of  galvanized-iron  of  the  shape  shown,  connected 
together  by  a  soft  solder  which  melts  at  approximately  165 
degrees.  These  are  approved  where  the  loads  to  which  the 
links  are  subjected  do  not  exceed  5  pounds,  where  a  factor  of 
safety  of  5  is  required. 


FIRE-RESISTING   WINDOWS,    SHUTTERS  AND   DOORS      489 


Fia. 


148.  —  Weight-reducing    De- 
vices for  Fusible  Links. 


Where     heavy   loads    must    be    controlled,    weight-reducing 
devices    may   be  employed  as  shown  in  Fig.  148.     Such  de- 
vices  are  made  for  use  under 
both    horizontal    and    vertical 
pulls. 

Trap  Doors,  closing  hori- 
zontally over  either  elevator  or 
stair  wells,  are  now  seldom 
employed.  Fire-resisting  verti- 
cal enclosures  and  doors  are 
much  to  be  preferred.  How- 
ever, if  used  for  elevators,  doors 
which  are  opened  and  closed 
by  the  moving  elevator  are  superior  to  other  devices. 

Double  Fire  Doors.  —  Openings  in  any  interior  fire  wall  — 
i.e.,  a  division  wall  between  two  separate  buildings  or  sections 
of  a  building  —  should  be  provided  with  approved  automatic 
sliding  or  rolling  fire  doors  on  each  side  of  the  wall;  or,  when 
acceptable  to  the  Underwriters  having  jurisdiction,  one  door 
may  be  made  sliding  or  rolling  and  the  other  swinging.  In 
other  words,  where  the  exposure  is  liable  to  be  severe,  —  as  at 
a  division-wall  opening  when  one  of  the  sections  or  buildings  is 
well  ablaze,  —  no  single  form  or  construction  of  door  now  in 
use  can  be  absolutely  counted  on. 

The  best  we  can  do  in  any  important  case  is  to  use  two 
fire  doors,  one  on  either  side  of  the  wall.  One  will  receive  the 
brunt  of  the  onslaught,  and  perhaps  in  the  course  of  half  an 
hour  or  an  hour  will  warp  or  break  down.  The  second,  shielded 
behind  the  first,  will  stand  up  to  its  work  until  any  ordinary 
fire  is  over.* 

Tin-covered  Doors.  —  Where  the  appearance  of  tin-clad  doors 
is  objectionable,  —  as,  for  instance,  in  department  stores  where 
several  more  or  less  old  buildings  are  connected  by  doorways 
in  party  walls,  —  it  is  customary  to  enclose  such  doors  in  es- 
pecially built  pockets.  These  are  often  made  of  metal  furring, 
metal  lath  and  plaster.  A  party-wall  pocket  for  a  single  sliding 
door  is  shown  in  Fig.  149.  For  double  doors,  the  arrangement 
shown  may  be  duplicated  on  the  other  side  of  the  wall.  Such 
pockets  also  possess  the  advantage  of  keeping  the  doors  free 

om  merchandise,  shelving,  etc. 

*  Mr,  John  R,  Freeman. 


490         FIRE   PREVENTION   AND   FIRE   PROTECTION 


'ki"Ls 


FIG.   149.  —  Party  Wall  Door  Pocket. 

Plate-iron  Doors.  —  Swing  plate-iron  doors  in  pairs,  on  both 
sides  of  wall,  are  shown  in  Fig.  150.  Doors  to  be  of  general  con- 
struction previously  given  for  standard  ''Vault  Pattern"  doors, 
also 

(6)  To  have  two  opposite  doors  fastened  together  by  hooks 
of  f-inch  round  iron,  bolts  or  spring  catches  at  top  and  bottom. 

(c)  Right-hand  door  to  fold  over  left-hand  door,  lapping 
at  least  one  inch,  or,  wheie  the  doors  are  flush,  to  fold  into 
rabbet  of  at  least  f  of  an  inch. 


FIRE-RESISTING    WINDOWS,    SHUTTERS   AND    DOORS      491 

(d)  Catches  to  be   of   ^-inch  Norway  iron  securely  riveted 
through  door  plate  and  angle-iron  panel  frame. 


FIG.   150.  —  Double  Plate-iron  Doors. 


Steel  Rolling  Doors.  —  For  openings  not  exceeding  8  feet  wide 
and  9  feet  high,  where  standard  sliding  doors  cannot  be  used  on 
account  of  interference  with  stairways,  elevator  enclosures,  etc., 
double  automatic  steel  rolling  doors  may  be  used  if  mounted  in 
the  reveal  on  each  side  of  wall,  overlapping  at  sides,  and  spring 
counterbalanced.  For  such  locations  the  "Abacus  No.  3"  door, 
manufactured  by  the  Kinnear  Manufacturing  Company,  may 
be  used  (see  Fig.  151). 

A  very  novel  and  effective  arrangement  of  double  steel  rolling 
doors  has  been  suggested  by  Mr.  James  G.  Wilson  for  proposed 
use  at  fire-wall  openings  in  storage  warehouse  buildings,  large 
department  stores  and  the  like.  The  idea  is  to  construct  solid 
masonry  division  walls  which  are  provided  with  arched  vestibules 
at  all  door  openings,  such  vestibules  to  be  formed  of  double 
masonry  walls  projecting  into  the  rooms  as  shown  in  Fig.  152. 
Each  vestibule  would  have  a  separate  ventilating  flue  running 


492 


FIRE    PREVENTION    AND    FIRE    PROTECTION 


up  in  one  of  the  side  piers,  so  that  heat  or  smoke  might  be  carried 
off.  Steel  rolling  doors  are  applied  at  both  entrances  to  each 
vestibule  in  such  a  manner  that  all  fixtures,  grooves,  brackets, 
etc.,  come  within  the  vestibule  space. 


ELEVATION  ,  VERTICAL  SECTION 

FIG.  151.  —  Double  Steel  Rolling  Doors,  Kinnear  "Abacus  No.  3." 


Fire-resisting  Qualities.  —  Two  sets  of  double  steel  rolling 
doors  have  been  tested  by  the  British  Fire  Prevention  Committee. 

11  Red  Book  "  No.  Ill  describes  a  test  to  record  the  effect  of  a 
fire  at  four  hours'  duration  at  a  temperature  gradually  increasing 
to  1800°  F.,  followed  by  the  application  of  water  for  five  minutes 
on  the  fire  side,  with  a  view  to  being  classified  as  affording  "Full 
protection,"  class  B. 


FIRE-RESISTING    WINDOWS,    SHUTTERS   AND    DOORS      493 

The  door  opening  was  7  feet  wide  by  8  feet  high.  On  either 
side  of  the  opening  in  a  14-inch  wall  were  placed  "Kinnear"  steel 
rolling  doors.  The  summary  of  test  is  given  as  follows:/ 


Flues- 


FIG.  152.  —  Double  Automatic  Rolling  Doors  with  Arched  Lobbies. 

After  two  hours  the  heat  radiated  through  the  shutters 
began  to  scorch  a  newspaper  on  a  wooden  post  placed  12  inches 
away  from  the  outer  face  of  the  outer  shutter.  After  2  hours 
and  45  minutes,  the  newspaper  and  wood  caught  fire.  No 
flames  passed  through  or  around  the  outer  shutter  or  over  the 
hood  during  the  four  hours  of  the  test.  Both  the  inner  and 
outer  shutters,  frames  and  gears  remained  intact.  The  maxi- 
mum bulge  on  the  inner  shutter  at  the  conclusion  of  the  test 
did  not  exceed  1J  inches.  The  maximum  warping  to  the  hood- 
protecting  gear  of  inner  shutter  did  not  exceed  3  inches.  The 
outer  shutter  retained  its  alignment.  Both  shutters  could  be 
easily  worked  and  raised  at  the  conclusion  of  the  test.  A 
break-down  of  the  testing  plant  prevented  classification. 

"Red  Book "  No.  135  describes  an  exactly  similar  test  of 
''Wilson77  steel  rolling  doors.  The  summary  of  test  is  given  as 
follows : 

At  the  conclusion  of  4  hours  the  wooden  blocks  with 
paper  attached,  placed  12  inches  in  front  of  thev  outside  of  the 
shutter,  were  not  burnt.  No  flame  passed  through  or  around 


494 


FIRE   PREVENTION   AND   FIRE   PROTECTION 


the  outer  shutter  or  over  the  hood  during  the  four  hours  of  the 
test.  Both  the  inner  and  outer  shutters,  frames  and  gear  re- 
mained in  position.  The  maximum  bulge  of  the  inner  shutter 
at  the  conclusion  of  the  test  did  not  exceed  6  inches.  The 
maximum  warping  of  the  hood-protecting  gear  of  inner  shutter 
did  not  exceed  4J  inches  at  the  conclusion  of  the  test.  The 
maximum  bulge  of  the  outer  shutter  at  the  conclusion  of  the 
test  was  |  inch.  The  outer  shutter  could  be  worked  and  raised 
at  the  conclusion  of  the  test.  Classification  'Full  protection/ 
class  B,  was  obtained. 

Rough  Door  Frames  and  Sills.  —  Unfinished  fire  doors 
such  as  tin-covered,  plate-  or  corrugated-iron,  etc.,  may  be  hung 
in  a  variety  of  ways,  but  the  rules  and  requirements  of  the 
National  Board  of  Fire  Underwriters  should  be  carefully  con- 
sulted, especially  as  regards  hardware,  etc. 

Swing  Doors  may  be  "hung  as  follows: 

(a)  Against  an  unplastered  brick  wall,  if  overlapping  at  sides 
and  top  at  least  4  inches,  hung  to  hinge  eyes  or  so-called  ''shutter 
hooks"  built  into  wall,  as  shown  in  Fig.  153. 


Hinge  Eye 


FIG.  153.  —  Swing  Fire  Door  Hung 
to  Hinge  Eyes. 


FIG.    154.  —  Swing   Fire    Door   in 
Wall  Reveal,  Hung  to  Hinge  Eyes. 


(6)  In  reveal  of  opening,  with  angle  iron  to  form  rabbet  se- 
cured by  expansion  bolts,  hung  to  hinge  eyes,  as  in  Fig.  154. 


V       TX 

Pintle 


FIG.   155.  —  Swing  Fire  Door  in 
Wall  Rabbet. 


FIG.   156.  —  Swing  Fire  Door  Hung 
to  Angle-iron  Frame. 


FIRE-RESISTING   WINDOWS,    SHUTTERS   AND    DOORS       495 


(c)  In  a  4-by  4-inch  truly  built  rabbet  in  the  brickwork,  so  that 
door  will  fit  snugly  in  same,  hung  to  hinge  eyes,  as  in  Fig.  155. 

(d)  In  an  angle-iron  rabbetted  frame,  as  is  most  commonly 
employed,  hung  to  pintles  riveted  to  the  frame,  as  in  Fig.  156. 

(e)  In  a  rabbetted   channel-iron   frame,   often  employed   in 
terra-cotta  or  other  interior  partitions,  hung  to  pintles,  or  on 
butts  tapped  to  frame,  as  in  Fig.  157. 


5"x  stf 


FIG.  157.  —  Swing  Fire  Door  Hung 
to  Channel-iron  Frame. 


FIG.  158.  —  Concrete  and  Angle- 
iron  Door  Sill. 


Sliding  Doors  may  be  hung 

(/)  Against  wall,  without  metal  door  frame,  but  closing  in 
" binders"  or  socket  knees. 

(g)  Against  wall,  without  metal  door  frame,  but  closing  against 
continuous  metal  stop. 

(h)  Same  as  either  /  or  g,  but  with  angle-iron  or  channel  frame 
added  at  opening  to  protect  jambs. 

(i)  Against  wall,  surrounded  by  fire-resisting  pocket,  as  pre- 
viously described. 

Sills.  —  On  account  of  the  number  of  methods  specified. 
Underwriters  having  jurisdiction  should  be  consulted  before 
the  installations  of  sills. 

(a)  To  be  of  concrete  not  less  than  4  inches  in  thickness 
and  placed  between  a  3^-by  5-by  flinch  angle  iron  on  each  side 
of  the  wall.  Angles  to  extend  at  least  6  inches  past  the  opening 
on  each  side.  Long  side  of  angles  to  rest  against  the  face  of 
the  wall  and  short  sides  to  extend  out  under  the  bottom  of  the 
door.  Angles  to  be  fastened  together  through  the  wall  by  J- 
inch  bolts  placed  close  to  each  side  of  the  wall  opening  and  not 
to  exceed  18  inches  apart  at  any  point.  Bolts  to  have  nuts  at 
each  end.  See  Fig.  158. 

Where  sliding  fire  doors  are  used  the  upper  face  of  the 
angle  should  be  notched  out  at  one  end  on  each  side  of  the  wall 
or  angles  drilled  and  f-inch  bolts  installed  so  as  to  permit  the 
proper  installation  of  the  stay  roll  for  holding  the  door  in  posi- 


496         FIRE   PREVENTION   AND   FIRE   PROTECTION 

tion.  In  new  buildings  this  should  be  done  before  the  angles 
are  installed. 

Where  the  wall  is  rabbetted  for  a  swinging  fire  door,  an 
iron  plate  not  less  than  f  inch  thick  and  5  inches  wide  may  be 
used  in  place  of  the  angle-iron  on  that  side  of  the  wall,  or. the 
angle-iron  may  be  installed  so  that  the  short  side  extends  into 
the  wall. 

(&)  To  be  constructed  as  specified  in  rule  (a)  and  covered 
by  J-inch  steel  plate  extending  out  flush  with  the  outer  edges  of 
the  angles  on  each  side  of  the  wall  and  held  securely  in  position 
by  f-inch  countersunk  machine  screws  spaced  not  to  exceed 
9  inches  apart. 

Checkered  steel  plate  is  recommended  for  the  top  of  this  sill  as 
it  is  less  likely  to  become  smooth  and  slippery. 

(c)  To  be  of  concrete  not  less  than  3^  inches  in  thickness 
and  placed  between  a  3J  X  6  X  f-inch  angle-iron  on  each  side 

^e  wall.  Angles  to  extend  at 
least  6  inches  past  the  opening  on 
each  side.  The  short  side  of  the 
angle  to  be  parallel  with  and  set 
out  4  inches  from  the  face  of  the 
wall. .  The  long  side  of  the  angle 
to  extend  into  the  wall.  Angles 
to  be  fastened  together  through 
the  wall. 

In  new  walls,  two  courses  of 
1  m      r-    K  i  A  r  «  A     the  brickwork  to  be  corbeled  out 

FIG.  159.-  Corbeted  Concrete  and     t      support    the    angle-iron,    the 
Angle-uon  Door  Sill.  upper    course    to   b!    1J    inches 

back  from  the  perpendicular  face  of  the  angle.     See  Fig.  159. 

Where  a  large  amount  of  heavy  trucking  is  done,  the 
concrete  should  be  at  least  6  inches  in  thickness,  the  iron  in- 
creased proportionately  and  three  courses  of  the  brick  corbeled 
out  to  the  outer  edges  of  the  sill. 

In  old  walls  Z-bars  made  of  two  4-inch  angles  f  inch  thick 
bolted  together,  or  equivalent  solid  Z  bars,  may  be  used  in  place 
of  the  angle-iron  and  corbeling.  The  concrete  to  be  not  less  than 
7  inches  in  thickness  and  the  Z-bars  fastened  together  by  J-inch 
wall  bolts  through  both  perpendicular  faces. 

^yhen  sliding  fire  doors  are  used  the  angles  or  Z-bars  should 
be  drilled  and  f-inch  bolts  installed  so  as  to  permit  the  proper 
installation  of  standard  sta}^  roll  for  holding  the  door  in  position. 
In  new  buildings  this  should  be  done  before  the  steel  work  is 
placed  in  the  sill. 

Where  the  wall  is  rabbetted  for  a  swinging  fire  door,  an 
iron  plate  not  less  than  f  inch  thick  and  8  inches  wide  may  be 
used  in  place  of  the  angle-iron  or  Z-bars  on  that  side  of  the  wall. 

(d)  To  be  of  wrought-iron  or  steel  plate  not  less  than  J 
inch  in  thickness  on  concrete  support  not  less  than  six  inches 
thick.     Concrete  support  and  steel  plate  to  be  built  into  wall 
at  least  six  inches  on  each  side  of  the  opening  and  extend  under 


FIRE-RESISTING   WINDOWS,    SHUTTERS   AND    DOORS       497 

and  flush  with  the  outer  surface  of  the  door.  Three  courses  of 
the  brickwork  under  sill  to  be  corbeled  out  flush  with  the  outer 
surface  on  each  side  of  the  wall. 

Checkered  steel  plate  is  recommended  for  the  top  of  this  sill, 
as  it  is  less  likely  to  become  smooth  and  slippery. 

Where  sliding  fire  doors  are  used  the  steel  plate  should  be 
notched  out  at  one  end  on  each  side  of  the  wall  so  as  to  permit  the 
proper  installation  of  the  stay  roll  for  holding  the  door  in  position. 
In  new  buildings  this  should  be  done  before  the  plate  is  installed. 

(e)  To  be  constructed  in  accordance  with  any  of  the  above 
methods,  raised  H  to  2  inches  above  the  surface  of  the  floor  and 
provided  with  inclines  on  each  side. 

Raised  sills  are  of  advantage  in  preventing  water  from  run- 
ning through  door  openings  at  time  of  fire. 

Underwriters  having  jurisdiction  should  be  consulted. 

Lintels.  —  A  brick  arch  is  preferable,  but  lintels  made  of 
steel  I-beams  may  be  used  when  installed  and  protected  as  re- 
quired by  Underwriters  having  jurisdiction. 

Stone  or  tin-clad  wood  lintels  are  not  approved. 

Jambs,  Trim,  etc.,  for  Finished  Fire  Doors.  —  The  corri- 
dor, partition,  stair  and  elevator  doors  previously  described 
must,  as  well  as  rough  fire  doors,  be  approved  not  only  as  to 
the  type  of  door  itself,  but  also  as  to  "size,  mounting,  hardware 
and  frame;"  and  a  study  of  the  fire  tests  previously  given  of 
doors  constructed  and  hung  in  various  fashions  will  show  that 
the  question  of  hanging  and  the  type  of  frame  is  often  a  very 
important  factor. 

Cement,  terra-cotta,  metal-covered  concrete,  fireproofed  wood, 
and  cast-iron  trim  have  previously  been  described  in  Chapter 
XIII.  There  remain  to  be  considered  kalamine  and  metallic 
frames  and  trim. 


FIG.    160.  —  Kalamine  Door  Trim. 


Kalamine  Frames  and  Trim    are    usually    furnished  for 
kalamine  doors  by  the  manufacturer  making  the  doors.     Kala- 


498 


FIRE    PREVENTION    AND    FIRE    PROTECTION 


mine  doors  are  sometimes  hung  in  angle-iron  or  channel  frames 
without  trim,  but  usually,  where  the  expense  of  a  kalamine  door 
is  warranted,  frame  and  trim  of  the  same  character  are  desired 
for  appearance. 

A  typical  kalamine  door  frame  and  casing,  over  a  rough  wooden 
frame,  are  shown  in  Fig.  141. 

A  better  detail,  combining  a  rough  channel-iron  frame  with 
kalamine  trim,  is  shown  in  Fig.  160. 

A  detail  of  kalamine  window  trim,  as  for  windows  in  an  in- 
terior 4- inch  partition,  is  shown  in  Fig.  161. 


FIG.   161.  —  Kalamine  Window  Trim. 

Metallic  Door  Trim.  —  Fig.  162  illustrates  Dahlstrom  me- 
tallic trim  surrounding  combination  slide  and  swing  elevator 
doors,  as  used  in  building  at  southeast  corner  of  Broadway  and 


FIG.  162.  —  "Dahlstrom"  Metallic  Door  Trim. 


FIRE-RESISTING   WINDOWS,    SHUTTERS   AND    DOORS       499 

77th  St.,   New  York.     These  doors  are  operated  similarly  to 
those  described  on  page  485. 

Special  Openings  and  Constructions.  —  Passenger  elevator 
enclosure  doors  may  be  of  kalamine  or  metallic  construction  as 
previously  described,  or  of  iron  and  wire  glass,  as  described 
in  Chapter  XVI. 

Freight  elevator  enclosure  doors  may  be  made  of  almost  any 
of  the  types  previously  described,  in  addition  to  which  a  few 
special  constructions  may  be  mentioned,  as  follows: 

Counter-balanced  (or  Meeker)  doors,  as  manufactured  by  the 
Richmond  Safety  Gate  Company,  Richmond,  Ind.,  are  applied 
to  the  inside  of  the  enclosure  and  are  arranged  in  two  sections. 
One  section  slides  upward,  the  other  downward. 

The  door  can  be  opened  to  the  full  height  of  opening,  and  when 
closed  forms  a  protection  from  fire,  at  the  same  time  affording 
the  employees  of  the  building  ample  protection  against  the 
danger  of  an  unguarded  hatchway. 

The  doors  slide  on  a  continuous  track  made  of  "Z"-bars  or 
angles  fastened  to  the  inside  of  the  hatchway,  and  are  supported 
by  heavy  cable  chains  which  operate  over  roller-bearing  sheaves 
riveted  to  the  track.  Doors  can  be  made  of  one  or  two-ply  flat- 
or  corrugated-iron  riveted  to  angle-iron  frame,  or  of  wood  covered 
with  lock-joint  tin  set  in  angle-iron  frames.  In  connection  with 
any  form  of  construction,  a  closing  device  with  or  without  an 
automatic  check  can  be  furnished  when  desired. 

Vertical  telescoping  doors  are  made  in  two  sections,  both 
sections  sliding  vertically.  The  arrangement  of  pulleys  is  such 
that  the  lower  section  maintains  a  speed  ratio  of  two  to  one  as 
compared  with  the  upper  section.  The  weight  necessary  for 
counter-balancing  a  door  of  this  type  is  approximately  three- 
fourths- of  the  total  weight  of  door. 

The  doors  slide  on  a  double  angle  track  fastened  to  the  wall 
and  are  supported  by  chains  or  cables  operating  over  roller- 
bearing  sheaves  fastened  to  the  track  and  upper  section  of  door. 
Doors  proper  are  usually  made  of  one-  or  two-ply  corrugated-iron, 
surrounded  by  and  riveted  to  angle-iron  frames.  Wood  paneled 
doors  or  doors  made  of  flat  sheets  can  also  be  furnished.  When 
installed  for  fire  protection  the  doors  are  provided  with  an  auto- 
matic closing  device. 

"  Peelle  "  and  "  Turnover  "  doors  are  described  in  Chapter 
XXVI. 


500         FIRE    PREVENTION   AND    FIRE    PROTECTION 

Care  and  Maintenance  of  Fire  Doors.  —  "Fire  doors 
should  be  ready  for  instant  use  at  all  times,  therefore  it  is  neces- 
sary to  keep  the  surroundings  clear  of  everything  that  would  be 
likely  to  obstruct  or  interfere  with  their  free  operation.  They 
should  be  kept  closed  and  fastened  at  night  and  on  Sundays  and 
holidays,  and  whenever  the  openings  are  not  in  use.  All  parts 
should  be  kept  thoroughly  painted. 

The  following  notice  should  be  posted  at  each  opening  pro- 
tected by  fire  doors,  preferably  stenciled  on  each  side  of  the 
fire  door  itself:  Keep  This  Fire  Door  Shut." 


CHAPTER  XV. 
STAIRWAYS   AND   FIRE   ESCAPES. 

INTERIOR  STAIRWAYS.* 

Requirements  in  Design.  —  The  theoretical  and  practical 
design  of  interior  stairways  involves  location,  isolation,  capacity 
and  general  safety,  as  well  as  a  knowledge  of  constructional 
details.  All  of  these  factors  are  matters  of  planning  and  design, 
subject,  of  course,  to  local  building  laws  in  force. 

Location.  —  Stairways,  to  be  safe  and  efficient,  must  be  lo- 
cated at  a  sufficient  number  of  readily  accessible  points  to  ac- 
commodate the  maximum  number  of  people  liable  to  use  them. 
(See  "  Means  of  Egress,"  Chapter  IX,  page  300,  and  "  Capacity 
of  Stairs,"  page  509.) 

It  is  a  great  mistake  to  relegate  stairs  to  almost  any  convenient 
location,  and  to  leave  the  layout  or  arrangement  of  the  runs  and 
platforms  to  be  fitted  in  as  may  be  found  possible  after  other  less 
important  considerations  have  been  allowed  to  determine  the 
stair  plan.  The  fact  that  stairs  are  relied  on  for  service  in  time 
of  possible  emergency  by  both  occupants  and  firemen  should  be 
sufficient  argument  to  provide  a  location  at  once  convenient  and 
safe,  and  a  plan  which  shall  be  simple,  without  unnecessary 
windings  or  confusing  turns;  in  fact,  as  simple  and  safe  a  con- 
struction as  may  be  devised. 

The  lighting  of  a  stair  well  will  often  determine  its  location, 
but  it  must  always  be  borne  in  mind  that,  in  city  blocks,  the  dan- 
ger from  external  fire  is  usually  quite  as  great  as  the  danger  from 
internal  sources.  Stairways  are  very  apt  to  be  lighted  from 
exterior  courts  or  areas  reserved  from  th  lot  limits  for  the  pur- 
pose of  light  and  ventilation.  These  may  be  of  very  restricted 
dimensions,  thus  bringing  the  windows  very  near  a  dangerous 
neighboring  risk.  The  safest  possible  exposure  should,  therefore, 
be  chosen  for  windows  lighting  stair  wells;  facing  blank  walls 

*  Stairways  in  theaters  and  schools,  etc.,  require  more  or  less  special  treat- 
ment. Hence  compare  with  Chapters  XXII  and  XXIII. 

501 


502 


FIRE    PREVENTION   AND    FIRE    PROTECTION 


if  practicable,  otherwise  the  windows  should  be  made  with  metal 
frames  and  sash  and  wire  glass. 

The  source  of  light  within  the  stair  well  will  also,  in  many  cases, 
serve  to  determine  the  shape  of  the  latter,  and  the  character  of 
its  enclosing  partitions.  If  lighted  from  an  overhead  skylight, 


FIG.   163.  —  Circular  Stairs  around  enclosed  Elevator  Shaft. 

the  surrounding  walls  may  be  made  of  brick  or  tile  if  the  plan 
provides  for  an  ample  light  well  down  the  center.  If  the  stairs 
must  be  wholly  or  largely  lighted  from  adjacent  floor  areas,  metal 
and  wire  glass  partitions  become  necessary. 

Stairways  should  never  surround  elevator  shafts  if  any  other 
independent  location  is  possible;  but  if,  on  account  of  limited 
room  or  for  other  reasons,  a  stairway  must  surround  an  elevator 


STAIRWAYS   AND    FIRE    ESCAPES 


503 


wellroom,  a  fire-resisting  and  smoke-proof  partition  should  sep- 
arate one  from  the  other.  Fig.  163  shows  a  circular  stairway 
surrounding  an  enclosed  elevator  shaft,  as  used  in  the  tower  of 
the  Park  Row  Building,  New  York  City,  R.  H.  Robertson, 
architect. 

A  clever  expedient  as  to  the  location  and  treatment  of  stairway 
was  carried  out  by  Messrs,  Peabody  and  Stearns,  architects,  in 
the  Chandler  store,  Boston.  This  was  to  place  the  stairway 
immediately  next  to  the  two  passenger  elevator  wells,  separating 
the  stairs  from  the  elevator  shaft  by  a  brick  wall,  but  treating  the 


FIG.    164.  —  Stairway  adjacent  to  Elevator  Well. 

opening, of  the  stair  well  on  to  the  various  floors  exactly  like 
the  adjacent  elevator  -fronts,  as  shown  in  Fig.  164.  Thus  the 
iron  pilasters  and  cornice  surrounding  the  elevator  openings  are 
also  carried  up  the  sides  and  across  the  heads  of  the  stair  openings, 
the  latter  being  closed  by  means  of  standing  panels  and  sliding 
doors,  all  of  same  design  as  the  elevator  front,  the  doors  being 
kept  open  by  means  of  fusible  links.  The  appearance  from  the 
floor  side  is,  therefore,  that  of  practically  three  elevators  side  by 
side,  but  in  case  of  any  sudden  rise  of  temperature  on  any  floor, 
the  melting  of  the  overhead  fusible  link  would  liberate  the  sliding 
stair  well  door,  which  would  then  close  by  gravity. 


504         FIRE    PREVENTION   AND    FIRE    PROTECTION 

Isolation  of  Stair  Wells.  —  The  importance  of  enclosing  all 
vertical  openings  such  as  stair  and  elevator  shafts  has  previously 
been  pointed  out.  See  "  Vertical  Openings,"  page  312. 

Many  practical  or  commercial  considerations  make  it  extremely 
difficult  to  reconcile  the  unquestioned  theoretical  advantages  of 
isolated  stair  wells  with  the  disadvantages  arising  from  such 
isolation;  for  when  the  requirements  of  adequate  fire  protection 
seriously  interfere  with  the  conventional  architectural  treatment 
of  the  building  or  with  commercial  necessities,  the  adoption  of  any 
innovations  to  secure  such  ends  is  almost  impossible  to  obtain. 
Thus  in  office  and  public  buildings  the  usual  conspicuous  loca- 
tion of  the  main  stairway  and  grille-work  elevator  enclosure  has 
resulted  in  making  these  items  among  the  most  prominent  archi- 
tectural features  of.  the  interior  design,  and  when  investors  in 
this  class  of  property  are  vying  with  one  another  to  provide  rich 
and  inviting  interiors  to  attract  tenants,  the  relegating  of  stairs 
and  elevators  to  isolated  and  protected  enclosures,  separated 
from  the  main  corridors  by  means  of  fire-resisting  doors,  would 
by  many  be  considered  the  height  of  folly  and  unnecessary  pre- 
caution. 

Again,  in  retail  stores  or  other  commercial  centers,  large  unob- 
structed and  easily  accessible  areas  are  demanded  to  create  the 
impression  of  magnitude,  to  present  to  the  vision  many  alluring 
displays,  and  to  render  the  interior  appointments  attractive  and 
artistic,  regardless  of  safety  in  time  of  possible  panic. 

But,  in  spite  of  the  plea  that  appearance  and  commercialism 
are  quite  as  important  as  safety,  it  is  still  unquestionably  true 
that  stair  and  elevator  shafts  should  be  completely  isolated  from 
the  floor  areas  by  means  of  fire-resisting  partition's  and  fire  doors, 
especially  in  all  buildings  accommodating  large  numbers  of 
people,  and  that  such  stairways  should  preferably  have  inde- 
pendent connection  with  the  sidewalks. 

Stairways  and  Exits.  —  No  building  should  have  less  than 
two  stairways  remote  from  each  other  and  enclosed  in  fireproof 
shafts  with  fire  doors  at  communications  to  floors.  Additional 
stairways  should  be  provided  when  necessary  so  that  no  point 
on  any  floor  will  be  more  than  90  feet  from  a  stairway.  Other 
approved  means  of  exit  such  as  protected  openings  through  fire 
walls  may  replace  to  advantage  one  or  more  stairways.  Revolv- 
ing doors  if  used  should  be  in  addition  to  the  necessary  exit  doors. 

There  was  only  one  continuous  stairway  in  the  Equitable 
Building.  The  fire  soon  cut  off  access  to  it  on  the  upper  floors, 


STAIRWAYS  AND   FIRE   ESCAPES  505 

and  the  first  collapse  of  the  floors  carried  away  part  of  the  stair 
landing.  Had  the  fire  occurred  during  business  hours  the  loss 
of  life  would  probably  have  been  appalling.  As  it  happened, 
three  persons  on  the  upper  floors  were  trapped.  They  jumped 
into  Cedar  Street  and  were  killed.  .  .  . 

This  fire  furnished  further  evidence  of  the  fact  that  the 
fire  department  cannot  be  expected  to  fight  fires  effectively  above 
the  5th  floor  of  buildings  except  by  means  of  smokeproof  towers 
and  6-inch  or  larger  standpipes  conveniently  accessible  thereto.* 

Unless  distinctly  required  by  the  local  building  laws,  it  is 
still  only  in  occasional  instances  that  such  stairways  are  pro- 
vided, even  in  so-called  fire-resisting  buildings.  But  building 
ordinances  are  gradually  requiring  the  extension  of  this  principle 
to  all  structures  liable  to  contain  many  people,  and  at  least  one 
stairway  is  now  often  required  to  be  enclosed  within  fire-resisting 
walls  for  all  such  buildings  as  hotels,  apartment  houses,  stores, 
factories  and  office  buildings.  As  to  schoolhouses,  opinions 
differ  regarding  the  cutting  off  of  stair  wells,  as  is  pointed  out  in 
Chapter  XXIII,  page  747. 

Enclosing  Partitions.  —  In  buildings  containing  any  ma- 
terial fire  hazard,  the  enclosures  around  vertical  openings  are 
second  only  in  importance  to  fire  walls.  The  latter  prevent 
horizontal  communication  of  fire;  the  former  prevent  the  vertical 
spread.  Hence  stair  enclosures  in  such  buildings  should  be  made 
of  a  construction  which  will  adequately  resist  the  severest  possible 
fire  and  water  test  to  which  the  structure  may  be  subjected,  and 
their  construction  should  especially  possess  rigidity  and  stability. 

Rigidity  is  necessary  for  the  proper  mounting  of  fire  doors. 
Thin  plaster  partitions  or  any  form  of  block  partitions  are  not 
satisfactory  from  this  standpoint,  as  such  constructions  possess 
little  rigidity  unless  braced  by  metal  door  bucks,  etc.  Such 
metal  reinforcements  are  liable  to  buckle  under  fire  test,  thus 
destroying  the  efficient  mounting  of  the  fire  doors. 

Stability  is  necessary  to  prevent  damage  in  the  wellrooms  of 
either  stairs  or  elevators,  caused  by  the  falling  of  partition  ma- 
terial. Experience  in  the  San  Francisco  fire  showed  that  block 
partitions  frequently  caused  the  wreck  of  stairways,  and  damage 
to  mechanical  equipment  by  falling  through  the  elevator  shafts 
to  the  basement.  Hence  solid  masonry  partitions  of  brick  or 
of  reinforced  concrete  are  decidedly  preferable. 

*  "  Report  on  Fire  in  the  Equitable  Building,"  by  F.  J.  T.  Stewart,  Superin- 
tendent, New  York  Board  of  Fire  Underwriters. 


506         FIRE    PREVENTION   AND   FIRE    PROTECTION 

Metal  and  Wire  Glass  Enclosures.  —  Any  stair  enclosure 
consisting  of  a  metal  framework  filled  in  with  wire  glass,  even 
although  completely  surrounding  the  stairs  and  landings  at  each 
and  every  floor,  can  only  be  rated  as  partial  protection.  Such 
construction  is  not  comparable  in  efficiency  to  either  brick, 
reinforced  concrete,  or  to  substantially -braced  terra-cotta  par- 
titions, but  where  considerations  of  appearance  or  light  preclude 
the  use  of  opaque  enclosures,  the  vertical  fire  hazard,  if  not 
severe,  may  be  practically  eliminated  by  the  use  of  wire  glass 
partitions  with  automatic  fire  doors. 

The  frameworks  of  such  enclosures  should  preferably  be  of 
cast-iron,  as  cast  metal  will  resist  distortion  by  heat  far  better 
than  steel  shapes.  A  typical  example  has  been  illustrated  in 
Fig.  164.  Similar  enclosures  have  been  used  in  many  of  the 
latest  examples  of  fire-resisting  hotels,  department  stores,  etc. 
Galvanized-iron  frames  in  combination  with  plate  glass  have 
been  used  in  some  instances,  but  such  constructions  would  prove 
practically  worthless  under  fire  test. 

Partial  Enclosures.  —  If  the  exigencies  of  the  building  plan 
or  design,  or  considerations  of  expense  absolutely  prohibit  the 
isolation  of  stairways  in  thoroughly  fire-resisting  enclosures, 
several  expedients  may  be  adopted  to  insure  the  cutting-off  of 
one  floor  from  another,  thus  preventing  the  stair  well  from  acting 
as  a  horizontal  means  of  fire  communication.  Thus  a  fire- 
resisting  enclosure  around  the  stair  well  at  every  alternate  floor 
will  prevent  the  well  from  acting  as  a  vertical  flue,  provided 
fire  doors  (held  open  by  means  of  approved  fusible  links)  are 
placed  at  the  start  of  the  flight  going  up,  and  at  the  landing  or 
top  of  the  flight  leading  down.  If  such  enclosures  are  placed 
on  the  second,  fourth, .  sixth  stories,  etc.,  an  ornamental  open 
staircase  may  still  be  retained  in  the  first  story;  but  this  make- 
shift renders  the  stairs  of  no  value  as  a  fire  escape,  and  decidedly 
insecure  for  use  by  firemen. 

Another  form  of  partial  enclosure  for  straight  runs  of  stairs 
may  be  made  by  placing  a  fire  door  at  the  head  of  each  flight  of 
stairs  and  then  filling  in  the  spaces  between  the  floors  arid  the 
soffits  of  the  stair  strings  with  partitions.  Such  partial  enclo- 
sures of  metal  framework  and  wire  glass  are  illustrated  in  Fig.  165. 
This  expedient  is  also  sufficient  to  eliminate  the  vertical  hazard 
under  very  moderate  conditions,  but  the  value  of  the  stairway 
as  a  fire  escape  is  slight. 


STAIRWAYS  AND    FIRE    ESCAPES 


507 


FIG.   165.  —  Partial  Stair  Enclosure  of  Metal  and  Wire  Glass. 

Improper  Enclosing  Walls.  —  A  common  mistake  in  stair 
design  and  location  lies  in  confounding  incombustibility  and  fire- 
resistance,  as,  for  instance,  enclosing  what  should  be  a  fire-re- 
sisting stairway  within  an  exterior  wall  made  of  cast-iron  and  glass. 
Such  enclosures  are  frequently  seen  —  sometimes  of  a  semi- 
circular shape,  protruding  from  the  main  wall  of  the  building, 
often  into  a  court  or  area;  or  even  as  an  integral  part  of  the 
structure  itself,  where  the  front  and  rear  portions  of  the  building 
are  built  to  the  full  lot  dimensions,  and  connected  near  the  center 
of  the  lot  area  by  a  connecting  passageway,  narrower  than  the 
front  and  rear  portions,  thus  leaving  light  and  ventilation  courts 
on  either  side.  Such  constructions  sometimes  have  a  load-carry- 
ing framework  of  steel,  which  is  simply  faced  or  ornamented  by 
cast-iron,  but  the  detail  is  also  common  of  making  such  designs 
entirely  of  cast-iron  columns  with  facias  or  ornamental  panels 
at  the  various  floor  levels,  so  arranged  as  to  provide  the  largest 
possible  window  areas,  the  whole  construction  being  thus  exposed 
to  possible  external  or  internal  fire.  Many  examples  of  such 
design  may  be  found,  in  which  the  sole  means  of  exit,  viz.>  the 


508         FIRE   PREVENTION   AND   FIRE    PROTECTION 

stairways  and  elevators,  are  placed  within  unprotected  frame- 
works of  cast-iron  and  glass,  regardless  of  the  character  of  the 
neighboring  buildings  abutting  the  light  courts.  If  such  adjacent 
structures  are  dangerous  risks  and  severe  fire  ensues,  the  expan- 
sion and  warping  of  the  exposed  framework  and  the  failure  of 
the  window  areas  is  almost  sure  to  result.  The  ultimate  effect 
will  be  the  stoppage  of  elevator  service,  and  the  distortion  or  un- 
safe condition  of  the  stairway,  if  not  the  complete  wrecking  of 
this  portion  of  the  building.  That  such  a  possibility  is  not  merely 
theoretical  speculation  is  sufficiently  attested  by  the  action  of 
such  cast  frameworks  in  several  well-recorded  instances.  In  the 
side  court  of  the  Home  Life  Building,  where  the  brunt  of  the  fire 
occurred  through  the  burning  of  the  adjacent  lower  building, 
the  expansion  of  the  cast-iron  sills  and  lintels  under  and  over 
the  windows  lighting  the  stair  well  and  elevator  shaft,  was  suffi- 
cient to  force  18-inch  brick  piers  about  an  inch  out  of  line,  and 
to  develop  cracks  in  the  masonry  from  the  same  cause.  Had  the 
construction  been  of  cast-iron  and  glass  only,  without  masonry 
walls,  far  more  distortion  and  damage  would  undoubtedly  have 
resulted. 

For  such  designs  in  metal  construction  cast-iron  is  much  to  be 
preferred  to  steel,  as  the  cast  metal  will  retain  its  shape  under 
severe  heat  far  better  than  thin  facings  or  frameworks  of  steel; 
but  a  much  better  and  safer  method  is  to  design  all  ornamental 
facings  or  coverings  so  that  their  warping  or  displacement  will 
not  affect  the  integrity  of  an  inner  protected  or  fireproof ed  load- 
carrying  framework. 

Reliable  Stair  Supports  Necessary.  —  If  stairs  are  sur- 
rounded by  brick  or  concrete  walls,  all  stringer  bearings  may  be 
made  in  and  upon  such  walls;  but  if  metal  lath  and  plaster  or 
block  partitions  are  employed,  such  constructions  cannot  be 
relied  upon  for  weight  bearing,  as  hose  streams,  falling  debris 
or  other  causes  may  result  in  damage  or  dislodgment  sufficient 
to  endanger  or  wreck  the  entire  stair  construction.  With  such 
partitions  the  wall  strings  must  be  supported  from  the  steel 
frame,  either  by  means  of  hangers  from  the  beams  above  or  by 
struts  from  the  beams  below. 

It  should  not  be  necessary  to  add  that  the  carrying  of  appar- 
ently fire-r  sisting  stairs  upon  non-fire-resisting  supports  is  little 
short  of  criminal,  yet  the  writer  recalls  several  instances  in  which 
expensive  iron  and  marble  stairs  have  been  carried  by  wooden 


STAIRWAYS  AND    FIRE   ESCAPES  509 

beams  in  the  floor  construction.  Fire-resisting  stairs  depending 
upon  such  supports,  or  stairs  with  non-fire-resisting  floor  land- 
ings, are  worse  than  the  cheapest  kind  of  inflammable  wood 
strings  and  platforms,  for  in  the  Iatt6r  case  the  firemen  at  least 
know  at  a  glance  that  such  constructions  are  not  to  be  trusted. 

Planning  of  Stairs.  —  Considering,  now,  the  detailed  design 
and  construction  of  fire-resisting  stairs  as  ordinarily  provided, 
it  will  be  seen  that  the  general  plan  or  arrangement  is  dependent 
upon  the  amount  of  available  space,  and  upon  the  height  between 
floors.  But,  whatever  the  conditions  of  space  and  height,  it  is 
further  necessary  to  observe  certain  limitations  as  to  width, 
rise  and  tread,  and  arrangement,  in  order  that  the  stairs  be  easy 
and  safe  of  use  and  roomy  enough  to  accommodate  a  maximum 
travel  in  one  direction,  or  to  permit  the  comfortable  passing  of 
those  going  in  opposite  directions. 

Capacity  of  Stairs.*  —  From  data  given  in  Chapter  XXII 
under  a  discussion  of  quick-emptying  tests  in  theaters,  it  is  very 
apparent  that  most  buildings  containing  any  considerable  num- 
ber of  persons  (save  theaters,  etc.,  designed  and  built  under  as 
ample  provisions  for  entrance  and  exit  stairs  as  are  recommended 
in  the  proposed  standard  ordinance  of  the  National  Fire  Protec- 
tion Association)  are  sadly  deficient  as  to  capacity  of  reliable 
exit  stairs.  Applying  the  same  method  of  calculation  to  mer- 
cantile buildings,  as  for  instance  a  department  store,  we  shall 
obtain  results  which  make  apparent  the  justice  of  Mr.  Porter's 
criticism  regarding  "unemptiable  buildings." 

Thus,  assume  a  small  department  store  of  six  stories  above  the 
ground,  with  but  one  stairway.  Such  a  one  as  the  writer  has  in 
mind  often  has  by  actual  count  as  many  as  200  persons  on  any 
of  one  or  more  floors  on  days  of  special  sales.  Then,  by  the 
method  of  calculation  followed  for  theaters,  the  width  of  that 

200 
flight  of  stairs  should  be  0      10  or  about  8  feet.     As  a  matter  of 

A    X    lO 

fact  the  actual  width  of  stairs  in  the  building  assumed  is  about 
4  feet.  But  even  this  deficiency  of  100  per  cent,  in  the  stair 
capacity  does  not  make  any  allowance  for  the  people  coming 
down  from  the  floors  above.  Properly,  if  the  building  were  to  be 
emptied  in  two  minutes,  every  story  of  that  store  should  be  pro- 
vided with  a  separate  stairway  to  the  street,  each  to  be  8  feet 
wide.  Or,  if  two  equally  accessible  stairways  per  story  were 

*  See  also  "  Capacity  of  Fire  Escapes,"  page  533. 


510         FIRE   PREVENTION    AND    FIRE   PROTECTION 

provided,  each  should  be  of  sufficient  capacity  to  accommodate 
two-thirds  of  the  persons  on  a  floor,  or  the  width  of  stairs  would 

-  X  200 

have  to  be  30      1Q  ,  or  5  feet  each,  still  disregarding  other  stories. 
£  X  lo 

The  capacity  of  stairs  serving  several  stories  of  average  height, 
of  a  width  capable  of  permitting  two  persons  to  pass  abreast,  is 
given  by  Mr.  Porter  as  30  persons  per  story.  Assuming  that  a 
4-foot  stairway  will  accommodate  three  persons  abreast,  the  limi- 
tation of  occupancy,  or  the  maximum  safe  allowable  number  of 
persons  per  story  for  the  example  assumed  above,  would  be  45. 

Of  course  neither  the  stair  capacity  shown  to  be  necessary  by 
the  above  calculations,  nor  limitation  of  occupancy,  to  the  extent 
indicated,  is  possible  of  attainment.*  Nevertheless,  "it  is  the 
surplus  people  above  the  capacity  of  the  stairways  who,  in  fire 
casualties,  have  been  the  ones  who  have  either  jumped  to  death 
or  been  burned  up,"  and  it  is  this  surplus  over  the  usual  stair 
capacity  which  must  be  provided  for  by  either: 

1.  Added  stair  capacity, 

2.  adequate  outside  fire  escapes,  or 

3.  "fo'-sectional,"  fire  walls,  as  described  in  Chapter  IX. 
Sooner  or  later,  all  building  ordinances  must  demand  at  least 

one  of  these  requisites.. 

Usual  Width  of  Stairs.  —  The  clear  width  of  stairs  used  for 
ordinary  light  traffic  should  never  be  less  than  three  feet.  In 
special  cases  of  minor  stairs  to  boiler  rooms,  sub-basements,  etc., 
used  at  infrequent  intervals  only  by  employes  of  the  building, 
this  width  may  be  reduced  to  two  feet.  For  stairs  subject  to 
considerable  use,  as  in  office  buildings,  a  minimum  width  of  four 
feet  is  preferable,  while  for  public  buildings,  such  as  schools, 
theaters  and  the  like,  a  width  of  five  feet  (unless  specified  wider 
by  building  ordinance)  is  more  satisfactory  for  emergency  use. 
Further  data  respecting  stairways  in  schools  and  theaters,  etc., 
are  given  in  Chapters  XXII  and  XXIII  respectively. 

Safety  of  Stairs.  —  When  considered  from  the  standpoint  of 
ordinary  service,  or  from  the  standpoint  of  emergency  egress, 
the  safety  of  stairways  is  dependent  not  only  upon  the  width, 
but  also  upon  the  questions  of  rise  and  tread,  turns  and  "wind- 
ers," and  intermediate  platforms,  etc.  Building  ordinances 

*  The  bearing  of  limitation  of  occupancy  upon  capacity  of  stairways  and 
fire  escapes  is,  however,  being  seriously  recognized.  Compare  with  New  Jersey, 
1911,  factory  laws,  pages  534  and  811. 


STAIRWAYS  AND    FIRE   ESCAPES  511 

usually  cover  full  requirements  as  to  these  features  for  theater 
buildings,  but  equal  consideration  is  necessary  in  any  other  type 
of  structure  liable  to  contain  many  persons. 

Rise  and  Tread.  —  The  ease  and  safety  of  a  stair  is  dependent 
upon  the  rise  and  tread  employed,  quite  as  much  as  upon  the 
width  or  plan.  The  rise  or  vertical  distance  between  steps  must 
not  be  too  great  for  easy  going,  nor  must  the  treads  or  steps  be 
too  small  or  narrow  to  comfortably  receive  the  foot.  An  ordinary 
and  very  satisfactory  rule  for  general  usage  is  to  make  the  sum 
of  the  rise  and  tread  about  17  \  inches,  as  the  higher  the  riser  the 
less  tread  is  usually  required  for  the  foot.  Thus  for  an  easy  and 
wide  public  stairs  a  rise  of  6^  inches  would  be  comfortable  with 
a  tread  of  11  or  12  inches;  an  office  stairs  would  be  easy  with  a 
rise  of  7i  inches  and  a  tread  of  10  inches.  Another  rule  is  to 
make  2  X  rise  +  tread  =  24,  or,  subtract  the  sum  of  two  risers 
from  24  inches  to  obtain  the  width  of  tread  in  inches.  For 
general  practice,  or  where  room  is  not  distinctly  limited,  8  inches 
should  be  taken  as  a  maximum  riser,  and  8  inches  as  a  mini- 
mum tread.  A  good  height  for  ordinary  risers  is  6f  inches  and 
for  treads  10 \  inches.  Different  widths  of  tread  or  different 
heights  of  risers  should  never  be  employed  in  one  and  the  same 
flight,  as  the  going  up  or  down  stairs  becomes  largely  a  mechanical 
operation,  and  any  sudden  change  in  tread  or  riser,  especially  the 
latter,  serves  to  derange  the  expected  step  up  or  down,  resulting 
in  jar  or  even  possible  danger. 

Winders.  —  Other  points  to  be  considered  in  the  ease  or  safety 
of  a  general  layout  are  involved  in  the  use  of  platforms  or  winders. 
Unless  some  form  of  curved  or  spiral  stairs  is  used,  turns  from 
one  direction  to  another  must  be  accomplished  either  by  intro- 
ducing an  intermediate  landing  or  platform  at  the  turn,  or  else 
by  using /'winders,"  that  is,  risers  which  approximately  radiate 
from  a  post  or  newel  at  the  angle  of  turn.  Ordinarily,  platforms 
are  far  preferable  to  winders,  both  on  account  of  safety  and  on 
account  of  their  use  as  resting  places,  but  winders  are,  neverthe- 
less, very  commonly  employed,  especially  where  a  given  number 
of  risers  must  be  accommodated  to  a  given  area  of  wellroom. 
Winders,  in  many  cities,  are  expressly  forbidden  for  use  in 
theaters  or  public  buildings.  The  New  York  law  is  perhaps 
typical  in  requiring  that  "  stairs  turning  at  an  angle  shall  have 
a  proper  landing,  without  winders,  introduced  at  said  turn." 

When  winders  are  used  they  are  commonly  made  one  inch  wide. 


512  FIRE    PREVENTION    AND    FIRE    PROTECTION 

or  even  less,  at  their  junction  with  the  newel  from  which  they 
radiate,  and,  as  the  tendency  in  going  up  or  down  stairs  is  to 
follow  the  railing  away  from  the  wall,  this  brings  the  line  of 
travel  usually  from  18  to  24  inches  away  from  the  newel  or  radiat- 
ing point  of  the  winders.  The  winders  should,  therefore,  be  wide 
enough  at  the  newel  to  give  a  tread  of  not  less  than  seven  inches 
on  the  line  of  travel.  A  safe  rule  for  the  layout  of  winders,  irre- 
spective of  building  department  regulations,  is  to  divide  the 
90  degree  arc  between  the  risers  at  right  angles  to  the  newel 
post,  into  three  equal  parts.  This  will  give  a  width  of  the 
winder  treads,  on  the  travel  line,  about  equal  to  the  ordinary 
tread. 

The  writer  knows  of  a  case  where  a  curved  or  elliptical  stair- 
way  was  built  in  a  large  department  store,  with  winders  so 
narrow  near  the  balustrade,  and  of  so  rapid  a  pitch,  that  it 
became  necessary  to  construct  a  secondary  hand  rail  some 
18  inches  inside  of  the  iron  stair  railing  to  keep  the  line  of  travel 
on  a  path  where  the  treads  were  sufficiently  wide  for  safety. 

Intermediate  Platforms.  —  Even  where  not  distinctly  nec- 
essary for  turns,  some  building  ordinances  require  intermediate 
platforms  or  landings  in  public  assembly  and  theater  buildings. 
Thus  for  buildings  used  as  places  of  "worship,  instruction  or 
entertainment,"  the  Chicago  law  specifies  that  "no  stairway 
shall  ascend  a  greater  height  than  eleven  feet  without  a  level 
landing,  which,  if  its  width  is  in  the  direction  of  the  run  of  the 
stairs,  shall  not  be  less  than  three  feet  wide,  or  which,  if  at  a  turn 
of  the  stairs,  shall  not  be  of  less  width  than  that  of  the  stairs." 
The  Boston  law  states  that  "there  shall  be  no  flights  of  stairs  of 
more  than  fifteen  or  less  than  three  steps  between  landings." 
The  New  York  law  requires  "proper  landings  introduced  at  con- 
venient distances." 

Strength  of  Stairs.  —  The  loads  for  which  stairs  must  be 
calculated  are  also  often  fixed  by  municipal  regulations,  but,  in 
absence  of  any  particular  requirements,  a  load  of  150  pounds  per 
square  foot  may  safely  be  used.  Reliable  experiments  show  that 
a  dense  crowd  of  people  may  weigh  from  140  to  150  pounds  per 
square  foot,  and  while  it  is  very  improbable  that  any  such  load 
would  ever  come  on  a  stairway,  even  in  time  of  panic,  still  the 
vibration  caused  by  a  rapidly  moving  number  would  not  make 
this  unit  load  excessive.  This  load  should  be  taken  over  an  area 
represented  by  the  "horizontal  plan  of  the  stairs,  while  the  length 


STAIRWAYS   AND   FIRE    ESCAPES  513 

or  span  of  stringers  or  supporting  members  must  be  taken  for 
the  full  inclined  length  between  supports.  It  is  only  in  extreme 
cases  that  any  particular  attention  need  be  paid  by  the  architect 
to  the  calculation  of  the  stringers,  and  even  then  it  is  best  left 
to  the  judgment  and  design  of  a  reputable  concern  familiar  with 
stair  construction.  In  ordinary  cases  the  architectural  propor- 
tions desired  will  give  stringers  of  greater  strength  than  actually 
required. 

DETAILS  OF  IRON  STAIRS 

Types  of  Iron  Strings.  —  The  type  of  stair  construction 
is  determined  by  the  design  of  the  face  string.  A  " closed" 
string  completely  covers  and  hides  the  ends  of  the  treads  and 
risers,  while  an  "open"  string  is  below  the  treads  and  risers, 
thus  allowing  them  to  project  over,  and  to  show  a  finish  on  the 
ends. 

Ordinary  Construction:  Closed  Strings.  —  The  cheapest 
and  simplest  form  of  closed  face  string  consists  of  a  steel  plate, 
to  the  inside  of  which  are  riveted  light  angles  or  cast  step  brackets 
usually  about  1  \  inches  by  \\  inches,  thus  forming  lips  or  flanges 
to  receive  the  treads  and  risers.  For  ordinary  rise  and  tread  a 
plate  ten  to  twelve  inches  wide  will  suffice  to  project  slightly 
above  the  nosing  lines  of  treads  and  to  extend  far  enough  below 
the  bottoms  of  risers  to  allow  the  attachment  of  the  shelf  angles. 
For  light  traffic  and.  not  excessive  spans  this  Width  of  string  will 
usually  give  sufficient  strength,  provided  the  thickness  is  not 
reduced  beyond  good  practice.  Plates  of  a  thickness  less  than 
one-fourth  inch  should  never  be  used.  Plate-iron  strings  are 
not  suitable  for  heavy  loads  or  long  spans,  as  they  possess  little 
lateral  strength.  Ornamentation  may  be  secured  by  apply- 
ing cast-iron  rosettes  to  the  string  face  at  intervals,  or  by  run- 
ning cast-  or  drawn-mouldings  along  the  edges,  or  by  planting 
mouldings  on  the  face  of  string  so  as  to  form  a  panel,  as  shown 
in  Fig.  166. 

If  required,  lateral  stiffness  and  increased  capacity  may  be 
secured  by  riveting  top  and  bottom  angles  to  the  outside  of  the 
stringer  plates,  thus  forming  a  channel  section,  or  as  is  still 
cheaper  and  better,  a  channel-iron  may  be  used  for  the  string. 
A  channel-iron  string  may  be  ornamented  by  means  of  applied 
cast-iron  rosettes  or  other  ornaments,  but  a  still  more  finished 


514 


FIRE    PREVENTION    AND    FIRE    PROTECTION 


appearance  may  be  secured  by  applying  cast-iron  mouldings  in 
the  angles  of  the  channel,  and  also  at  the  ends  against  the  newels, 


FIG.   166. —  Stairs  with  Closed  Plate  String,  Perkins  Institution  for  BL: 
Watertown,  Mass. 

thus  forming  a  paneled  face  which  can  still  further  be  enriched 
by  applying  rosettes  within  the  panel.  Channel-iron  strings  of 
these  types  are  largely  used,  especially  in  office  and  mercantile 
buildings. 

Where  considerable  ornamentation  is  required,  or  even  when 
simple  mouldings  alone  are  used,  closed  strings  may  be  made  of 
cast-iron.  It  is  often  thought  that  the  comparative  unreliability 
of  cast-iron  makes  this  metal  unfit  for  any  save  very  short  runs, 
but  if  the  work  is  executed  by  a  reliable  foundry,  used  to  stair 


STAIRWAYS   AND    FIRE    ESCAPES 


515 


construction,  there  is  no  reason  why  perfectly  safe  and  satis- 
factory strings  cannot  be  made,  even  of  very  considerable  length. 


FIG.  167.  —  Closed  Cast-iron  Strings,  Stairs  in  Central  National  Bank,  N.Y. 


Fig.  167  shows  an  ornamented  cast-iron  string,  ornamented 
cast-iron  risers,  and  marble  treads  and  platforms.  Fig.  168  shows 
how  closed  cast-iron  strings  of  separate  flights,  leading  in  opposite 
directions,  may  be  constructed  so  as  to  lie  in  the  same  plane, 
joining  at  the  newel  at  platform  level.  In  all  of  these  forms  of 


516         FIRE   PREVENTION   AND   FIRE   PROTECTION 

cast  strings,  the  brackets  or  lugs  to  support  the  treads  and  risers 
arc  almost  always  cast  as  a  part  of  the  r.tring. 


FIG.   168.  —  Closed  Cast-iron  Strings  with  Successive  Runs  in  Same  Plane. 

"Box"  Strings.  —  The  most  elaborate  and  expensive  form  of 
closed  face  string  is  the  " boxed''  section,  which  may  be  employed 
where  a  very  heavy  or  massive  construction  is  to  be  indicated. 
This  is  usually  made  of  some  form  of  supporting  steel  string, 
either  a  single  plate,  plate  and  angles,  channel  or  I-beam,  sur- 
rounded either  wholly  or  in  part  by  an  ornamental  cast-iron  box- 
ing or  facing.  Thus  Fig.  169  shows  a  string  made  of  a  plate  and 
angles,  with  a  cast-iron  moulded  casing  applied  on  the  outside. 
The  bottom  bar  of  the  railing  covers  the  joint  between  the  two. 


STAIRWAYS  AND    FIRE   ESCAPES 


517 


Rail 


Steel 
Plate 


Angle  brackets  are  riveted  to  the  steel 
string  to  receive  the  cross  angles  which 
support  the  marble  treads  and  risers.  , 

Fig.  170  shows  a  still  more  elaborate 
string,  where  the  supporting  channel' is 
not  visible  after  the  completion  of  the 
stairs.  The  inside  cast-iron  covering  is 
made  of  the  "cut"  or  " notched"  form, 
to  follow  the  line  of  the  treads  and  risers. 
A  center  string  and  also  the  soffit  furring 
for  plastering  are  indicated. 

Open  Strings.  —  The  simplest  type 

of  open  string  is  constructed  of  a  bar  FlG'  169'  ~  Box  String" 
or  plate  with  angle-iron  step  brackets  riveted  along  and  above 
the  upper  edge.  As  this  gives  a  cheap  and  unfinished  ap- 
pearance, the  use  of  such  strings  is  generally  limited  to  fire 
escapes  or  to  lear  service  stairs  of  the  cheapest  character.  A 
stronger  and  better  appearing  construction  is  shown  in  Fig.  171, 


FIG.    170.  —  Box  String. 

where  cast-iron  step  brackets,  plain  or  paneled,  are  placed  upon 
the  upper  flange  of  the  channel  string.  Similar  cast  step  brackets 
may  also  be  used  over  I-beam  strings  to  support  marble  treads 
and  risers.  In  both  cases  the  brackets  are  rebated  to  receive  the 
angle  irons  which  carry  the  treads  and  risers.  This  is  the  ordi- 
nary construction  for  entrance  steps,  where  the  construction  is 
entirely  below  and  hidden  from  sight. 


518 


FIRE    PREVENTION    AND    FIRE    PROTECTION 


An  open  string  in  cast-iron  is  shown  in  Fig.  172.  The  marble 
treads  in  such  cases  are  usually  made  to  project  slightly  over  the 
face  of  the  string,  with  rounded  edges,  thus  giving  a  pleasing 
finish  and  ornamental  appearance.  Unless  made  very  deep, 
such  open  or  "cut"  strings  in  cast-iron  must  be  limited  to  com- 
paratively short  spans,  as  the  strength  of  the  string  must  be 
measured  from  bottom  of  riser  to  bottom  of  string. 


FIG.    171.  —  Open  String. 


Wall  Strings,  or  those  strings  coming  against  the  wall  sur- 
faces, may  be  made  of  steel  plates,  steel  channels  or  cast-iron. 
If  the  wall  is  unplastered,  plate-iron  strings  may  be  placed  directly 
against  the  wall  surface;  but  if  the  wall  is  to  be  plastered,  the 
wall  string  must  be  arranged  to  act  as  a  stop  for  the  plaster. 
This  may  be  accomplished  by  using  channel-iron  strings-,  in 
which  case  the  flanges  of  the  channel  are  placed  hard  against 
the  masonry  wall,  the  plastering  finishing  down  to  and  up  to 
the  upper  and  lower  flanges;  or  by  using  plate-iron  strings  with 
filler  blocks  behind,  as  in  Fig.  166.  Light  angles  are  often  used 
instead  of  filler  blocks.  A  still  more  finished  appearance  may  be 
secured  by  using  top  and  bottom  mouldings,  either  applied  to  a 
plate  as  in  Fig.  166,  or  made  as  a  portion  of  a  cast-iron  string. 

Plastered  Soffits.  —  If  the  stair  soffit  or  ceiling  is  to  be  plas- 
tered, lugs  should  be  cast  on,  or  light  angles  should  be  fastened  to, 


STAIRWAYS   AND    FIRE    ESCAPES 


519 


both  wall  and  face  strings,  to  receive  light  bars,  angles  or  channels, 
spaced  not  over  12  inches  centers.,  for  the  support  of  the- metal 
lath  and  plaster. 


FIG.   172.  —  Open  String  as  used  in  Produce  Exchange,  N.  Y. 

Intermediate  Strings.  —  For  very  wide  stairs,  center  or  in- 
termediate strings  are  necessary.  These  are  usually  made  of 
beams  or  channels  with  cast-iron  step  brackets,  as  previously 
described,  and,  if  the  soffit  is  to  be  plastered,  the  outside  strings 
must  be  made  sufficiently  deep  to  line  with  the  bottom  of  the 
center  string. 

Newels.  —  The  excellence  of  detail  in  stair  construction  is 
largely  dependent  upon  the  newel  or  post  detail.  As  the  newels 
occur  at  the  string  intersections  and  form  the  means  of  connecting 
the  strings  of  different  runs,  they  may  either  serve  to  hide  what 
would  otherwise  prove  unsightly  construction,  or  else  aggravate 


520         FIRE   PREVENTION    AND    FIRE    PROTECTION 

the  unsightliness  by  making  the  necessary  lugs  or  bolted  connec- 
tions more  prominent.  Except  in  the  very  cheapest  construc- 
tion, where  gas-pipe  newels  are  frequently  employed,  newels  are 
made  of  cast-iron,  cored  hollow,  and  paneled,  fluted  or  modeled 
as  may  be  desired  for  architectural  effect.  They  may  be  cast 
whole  in  one  piece,  except  the  caps  and  drops,  which  are  bolted 
on  to  the  top  and  bottom  afterward;  they  may  be  cast  in  two 
halves  which  are  mitered  together  at  opposite  corners;  they  may 
have  the  base  slotted,  so  as  to  fit  over  and  around  the  string; 
or,  where  cast-iron  face  strings  are  used,  the  newel  base  is  some- 
times cast  on  and  as  a  portion  of  the  string.  In  the  latter  case, 
the  separate  shaft  of  newel  is  fastened  to  the  base  by  means  of 
long  bolts  which,  when  drawn  up  tight,  make  apparently  one 
piece  of  the  base,  the  shaft  and  the  cap  and  drop  pieces. 

Connections  of  strings  to  newels  may  be  made  by  means  of  ' 
lugs  or  flanges  cast  on  the  newels  to  receive  the  ends  of  strings, 
or  angle-iron  knees  at  ends  of  strings  may  be  " tapped"  to  the 
newels. 

Various  newel  designs  are  shown  in  Figs.  166,  167  and  168. 

Risers.  —  Risers  may  be  made  of  wrought-iron  or  steel  plates, 
cast-iron,  slate  or  marble.  For  cheap  service  stairs,  and  es- 
pecially in  outside  fire  escape  design,  risers  are  often  omitted 
entirely,  but  this  is  not  to  be  advised  where  anything  better  than 
a  ladder  construction  is  desired.  The  cheapest  form  of  metal 
riser  is  sheet-iron  about  J  inch  thick,  the  plates  being  flanged  or 
bent  at  top  and  bottom  to  connect  with  the  treads.  The  more 
ordinary  riser  is  of  cast-iron,  which,  if  showing  in  the  construc- 
tion, may  readily  be  ornamented  by  paneling  the  face,  or  by 
moulding  such  ornamental  design  as  may  be  desired  (see  Fig.  167 
where  the  conventional  Greek  border  is  used  as  ornamentation). 
Cast  risers  are  usually  made  about  J-  inch  to  §  inch  in  thickness, 
with  flanges  or  lips  along  the  top  and  bottom  for  the  support  or 
connection  of  the  treads.  If  metal  treads  are  used,  they  arc 
bolted  to  these  flanges  on  the  risers,  while  if  marble  or  slate 
treads  are  employed,  the  riser  flanges  are  often  cast  with  three 
or  four  small  lugs  or  projecting  knobs,  about  i  inch  diameter 
and  i  inch  high,  over  which  the  treads  are  fitted.  Perforated 
cast-iron  risers  are  often  used  for  architectural  effect,  or  to  per- 
mit the  passage  of  light;  or  they  may  be  used  behind  marble 
risers,  thus  showing  a  marble  finish  from  the  front,  and  an  iron 
pattern  over  marble  from  the  rear. 


STAIRWAYS   AND    FIRE    ESCAPES  521  , 

Treads  and  Landings.  —  Treads  may  be  of  cast-iron,  slate 
or  marble.  In  very  cheap  construction,  like  outside  fire  escapes, 
grating  treads  of  flat  or  round  bars  are  often  used.  Those  of 
cast  metal  are  from  A  inch  to  i  inch  in  thickness,  usually  cast 
with  rounded  nosings  along  the  exposed  edges,  and  with  "  check- 
ered," " corrugated"  or  "  diamond  pattern"  surface,  so  roughened 
to  provide  a  more  secure  foothold  than  would  be  provided  by  a 
smooth  metal  surface.  Cast-iron  treads  may  be  bolted  to  the 
flanges  provided  on  the  strings  and  risers,  or  flanges  may  be  cast 
on  the  ends  of  the  treads,  through  which  bolted  connections  may 
be  made  direct  to  the  strings. 

Where  marble  treads  and  risers  are  used,  it  is  also  necessary  to 
provide  some  form  of  wrought-  or  cast-iron  riser  as  a  support,  as 
marble  risers  should  never  be  considered  as  having  any  carrying 
capacity.  This  may  be  accomplished  either  by  using  visible 
perforated  cast  risers  as  above  described,  —  falso  risers  of  cast- 
iron  behind  the  marble  risers,  as  shown  in  Fig.  170,  —  or  else  by 
using  angle-iron  supports  which  may  or  may  not  show,  according 
as  the  soffit  is  open  or  plastered.  Angles  are  arranged  as  shown 
in  Fig.  171,  being  placed  at  both  the  front  and  back  edges  of 
treads,  and  calculated  for  the  whole  tread  load.  The  angles 
should  be  stiff  enough  to  resist  deflection,  so  as  to  avoid  the 
possibility  of  cracking  the  marble  work. 

Slate  or  marble  treads  are  usually  specified  of  a  thickness  from 
1 J  to  2  inches,  with  rubbed  surfaces  and  with  rounded  nosings  on 
all  exposed  edges.  They  are  usually  bedded  in  black  putty  or 
plaster  of  Paris,  and  this  will  generally  make  them  secure,  es- 
pecially if  lugs  or  dowels,  cast  on  the  front  riser  flanges,  are  let  in. 
They  are  sometimes  fastened  by  means  of  wood  screws,  driven 
from  below  into  wood  plugs  let  into  the  treads. 

Landings  or  platforms  are  made  of  cast-iron,  slate  or  marble. 
If  of  cast-iron,  medium-sized  platforms  may  be  strengthened  by 
means  of  stiffening  ribs  cast  as  a  part  of  the  platform  plate  on 
the  under  side.  Larger  areas,  also  slate  and  marble  platforms, 
are  supported  by  means  of  tee  irons,  which  are  framed  from  string 
to  string,  or  from  riser  to  string. 

Unreliability  of  Slate  and  Marble  Treads  and  Platforms. 
—  Probably  the  most  ordinary  defect  in  so-called  fire-resisting 
stairs  lies  in  the  improper  use  of  slate  and  marble  treads  and 
platforms.  These  are  generally  supposed  to  be  fire-resisting  in 
themselves,  but  abundant  experience  has  proved  the  contrary. 


.  522         FIRE    PREVENTION   AND    FIRE    PROTECTION 

A  specific  example  occurred  in  the  burning  of  the  Temple  Court 
and  Manhattan  Savings  Bank  buildings  in  New  York  City, 
where  "the  slate  treads  of  the  stairways  yielded  to  the  heat, 
leaving  the  staircase  with  openings  the  full  size  of  the  treads, 
thus  making  the  stairs  impassable."  This  fire  occurred  in  1895, 
and  the  foregoing  criticism  is  quoted  from  Engineering  News. 

Other  similar  experiences  have  been  recorded,  one  of  which 
resulted  in  the  death  of  a  fire  department  captain  in  the  New 
York  City  service.  The  fire  in  question  occurred  in  1903  in  the 
Roosevelt  Building,  Broadway  and  Thirteenth  street,  New 
York.*  The  main  stairway,  in  the  central  portion  of  the  build- 
ing, was  of  metal  construction,  but  with  marble  treads  and 
platforms,  unsupported  by  metal,  except  along  the  bearing 
edges.  These  treads,  in  the  sixth,  seventh  and  eighth  stories, 
were  subjected  to  a  high  temperature,  resulting  from  a  severe 
fire  in  this  portion  of  the  building,  and  subsequently  enormous 
volumes  of  water  were  poured  into  this  stair  shaft  by  the  fire 
department.  Toward  the  end  of  the  fire,  a  captain  of  one  of  the 
fire  companies,  in  backing  his  hose  stream  out  of  the  sixth  or 
seventh  story  upon  the  supposedly  safe  stair  landing,  fell  through 
the  cracked  and  disintegrated  marble  slab,  and  thence  through 
the  successive  platforms  in  the  stairs  of  the  lower  stories  to  the 
basement  of  the  building.  The  fall,  of  course,  resulted  fatally, 
and  subsequent  examination  failed  to  determine  whether  the 
marble  platforms  were  first  broken  through  by  falling  roof 
debris,  caused  by  unprotected  roof  columns,  or  whether  the 
marble  slabs  had  been  so  cracked  and  weakened  by  fire  that  they 
failed  to  support  the  weight  of  the  fireman,  who,  in  falling  from 
such  a  height  broke  through  the  platforms  below.  In  either 
case,  the  members  of  the  fire  department  had  a  right  to  expect 
fire-resisting  stair  construction,  and  had  the  marble  treads  and 
platforms  been  placed  over  and  upon  sub-treads  of  iron,  it  is 
extremely  improbable  that  they  would  have  been  broken  through, 
even  by  falling  de'bris. 

Sub-treads  under  Slate  and  Marble.  —  Notwithstanding 
the  fact  that  such  experiences  as  the  foregoing  have  proved  them 
wholly  unreliable,  unsupported  slate,  bluestone  or  marble  treads 
and  platforms  may  be  found  in  many  public  buildings,  hotels, 
apartment  houses  and  office  buildings;  and  it  was  not. until  the 
revised* building  laws  of  Greater  New  York  were  put  into  effect, 

*  See  Chapter  VI,  page  152,  for  further  description  of  this  fire. 


STAIRWAYS   AND    FIRE    ESCAPES  523 

in  1900,  that  this  fundamental  defect  was  recognized  by  the 
building  laws  of  any  large  city.  The  fault  is  entirely  due  to  the 
prevalent  construction,  which  is  simply  to  rest  the  marble  or 
slate  treads  and  platforms  upon  the  riser  flanges  or  cross-bearing 
angles,  and  upon  the  flanges  cast  on  or  riveted  to  the  strings. 
To  make  the  construction  perfectly  safe,  and  even  more  orna- 
mental and  pleasing  in  the  case  of  open  or  exposed  soffits,  re- 
quires only  that  cast-iron  sub-treads  or  platforms  be  used  under 
the  marble  or  slate,  of  some  open  or  perforated  pattern,  thus 
showing  the  marble  surface  -through  the  ornamented  design. 
Then,  if  fire  occurs  severe  enough  to  crack  or  crumble  the  marble 
treads,  there  will  still  remain  the  cast  under  treads  as  a  firm 
support.  If  plastered  soffits  are  used,  plain  plate-iron  sub- 
treads  and  landing  surfaces  may  be  used  at  less  expense. 

The  present  New  York  building  law  requires  the  following 
provisions  for  the  support  of  slate  or  stone  stair  treads: 

In  all  buildings  hereafter  erected  of  more  than  seven  stories 
in  height,  where  the  treads  and  landings  of  iron  stairs  are  of  slate, 
marble  or  other  stone,  they  shall  each  be  supported  directly 
underneath,  for  their  entire  length  and  width,  by  an  iron  plate 
made  solid  or  having  openings  not  exceeding  four  inches  square  in 
same,  of  adequate  strength  and  securely  fastened  to  the  strings. 
In  case  such  supporting  plates  be  made  solid,  the  treads  may  be 
of  oak,  not  less  than  If  inches  thick. 

In  the  writer's  opinion,  this  law  should  apply  equally  well  to 
buildings  of  a  height  less  than  seven  stories. 

If  the  expense  of  both  iron  and  marble  or  slate  treads  is  con- 
sidered too  great,  the  staircase  should  then  be  made  with  cast- 
iron  treads  and  landings. 

Safety  Treads.  —  If  of  cast-iron,  all  treads  and  landings 
should  preferably  be  provided  with  some  form  of  safety  tread. 
Such  non-slipping  treads  are  made  of  combinations  of  lead  with 
grooved  steel  plates  or  wire  netting.  These  are  manufactured  in 
varying  widths,  both  with  and  without  nosings.  The  strips  are 
usually  4,  5  or  6  inches  wide,  extending  the  full  length  of  the 
tread  to  within  about  3  inches  from  the  string  lines.  They  are 
screwed  to  the  cast-iron  in  recesses  or  "rebates,"  cast  in  the 
treads  and  landings.  Marble  treads  are  also  often  provided  with 
safety  treads.  The  "Mason"  Safety  Tread,  manufactured  by 
the  American  Mason  Safety  Tread  Company  is  most  widely 
used. 


524        FIRE    PREVENTION    AND    FIRE    PROTECTION 

Asphalt  and  Rubber  Treads,  etc.  —  For  schools  and  similar 
buildings,  the  treads  and  landings  are  often  " rebated"  to  a 
sufficient  depth  and  over  sufficient  areas  to  receive  a  thin  layer 
of  asphalt  or  other  plastic  materials,  thus  securing  a  non-slipping 
and  slow- wearing  surface.  See  Fig.  166.  In  hospitals  and  like 
buildings,  where  noise  and  ease  of  going  are  important  consid- 
erations, the  cast  treads  and  platforms  are  often  rebated  for  cork 
tile,  or  for  rubber  mats.  The  latter  may  be  made  either  of 
smooth  or  corrugated  rubber  in  sheets,  or  of  some  interlocking 
pattern  of  small  pieces.  The  latter  form  may  be  obtained  in 
several  colors  and  of  pleasing  designs. 

Railings  and  Hand  Rails.  —  Railings  are  required  around 
all  well-hole  openings,  and  on  all  open  sides  of  the  stair  runs. 
These  may  be  constructed  according  to  the  architect's  fancy, 
from  plain  upright  square  or  round  bars,  spaced  one  or  two  to  a 
tread  (as  in  Fig.  166),  to  very  elaborate  designs  in  cast  or  wrought 
iron.  The  only  points  necessary  to  care  for  in  the  design,  save 
cost,  are  stiffness  and  height.  The  railings  should  be  stiff  enough 
in  the  design,  or  else  be  braced  often  enough,  to  resist  the  pressure 
of  persons  leaning  against  them,  and  the  height  should  be  such  as 
to  make  the  top  rail  at  a  convenient  level  for  the  grasp  of  the 
hand.  A  height  of  3  feet  is  usually  provided  from  the  center  of 
the  tread  to  the  top  of  the  hand  rail. 

Railings  usually  rest  on  the  top  of  the  string,  being  fastened 
thereto  by  means  of  tap  screws,  and  are  also  secured  to  the 
newels.  Fig.  172  shows  a  rail  made  of  cast-iron  panels,  with 
wrought  balusters  which  run  down  and  into  cast  sockets  secured 
to  the  string  face.  Figs.  167,  and  168  show  ornamental  rails 
executed  in  cast-iron. 

Hand  rails  are  usually  of  wood,  but  are  sometimes  made  of 
gas  pipe,  especially  for  service  stairs  or  those  in  boiler  rooms,  etc. 
They  are  fastened  to  the  top  bar  of  the  railing. 

Wall  Rails.  —  Wall  hand  rails,  secured  to  bronze  or  iron 
brackets  projecting  from  the  wall  surfaces,  are  usually  specified 
on  wide  stairs  subject  to  considerable  traffic,  and  especially  for 
theater  or  public  stairs. 

Fascias.  —  "Fascias"  or  " casings"  must  be  provided  to  cover 
those  exposed  portions  of  the  floor  construction  showing  in  the 
wellroom.  These  are  usually  paneled,  or  of  the  same  face  design 
as  the  strings,  and  extend  from  the  plaster  ceiling  to  the  finished 
floor  line.  The  bottom  line  of  fascia  usually  has  a  "stop"  or 


STAIRWAYS   AND    FIRE    ESCAPES 


525 


flange  against  which  the  plaster  ceiling  finishes.  The  top  edge 
of  fascia  is  sometimes  carried  above  the  floor  line,  thus  forming  a 
base  member  for  the  level  floor  railing. 

Terra-cotta  Block  Stairs.  —  In  the  model  fire-resisting  build- 
ing of  the  Underwriters'  Laboratories,  Incorporated,  Chicago, 
the  stairways  are  constructed  of  smooth-finish  hollow-tile  blocks 
of  the  shape  shown  in  Fig.  173.  Each  step  consists  of  a  one- 
piece  block,  made  with  moulded  nosing,  and  of  sufficient  length 


FIG.    173.  —  Terra-cotta  Block  Stairs. 

to  give  a  4-foot  clear  stairway  after  the  ends  are  built  into  the 
surrounding  walls  or  partitions.  A  central  6i-mch  double-tile 
partition  separates  the  runs,  thus  dispensing  with  balustrades. 
The  landings  aie  also  constructed  of  tile. 

A  construction  similar  to  the  above,  except  that  the  step 
blocks  were  built  into  surrounding  partitions  around  one  side  of 
stair  well  only,  was  previously  used  (1903)  in  the  Amelia  Apart- 
ments, Akron,  Ohio. 

Guastavino  Stairs.  —  For  buildings  of  a  monumental  char- 
acter, such  as  art  museums,  libraries,  state  and  municipal  build- 
ings, etc.,  masonry  stair  construction  is  often  desired  as  more  in 
keeping  with  the  architectural  effect.  In  many  such  cases,  as 
well  as  in  buildings  of  less  importance,  the  Guastavino  stair 
system  has  been  adopted. 

For  rectangular  wells  this  construction  consists  of  a  series  of 
superimposed  catenarian  arches,  with  rough  masonry  treads 
built  chereon  for  the  receipt  of  the  finished  treads  and  risers. 
Fig.  174  illustrates  one  of  the  eighty  flights  constructed  (1911) 
in  the  wool  warehouses  of  the  Boston  Wharf  Company,  Boston, 
Mass.  Each  arch  consists  of  two  courses  of  tile,  on  which  rough 


526         FIRE    PREVENTION   AND   FIRE    PROTECTION 

brick  treads  and  risers  are  built.  The  risers  ate  then  faced  with 
cement  while  the  finished  treads  consist  of  perforated  cast-iron 
filled  in  with  cement. 


FIG.   174.  — Guastavino  Stair  Construction. 

In  circular  wells,  continuous  spiral  flights  are  constructed. 
Both  types,  although  very  light  in  appearance,  have  been  thor- 
oughly tested  as  to  strength,  and  a  number  of  such  constructions 
have  safely  endured  severe  fire  tests. 

Concrete  Stairs  may  be  constructed  of: 

1.  The  slab  method,  consisting  of  inclined  slabs  of  reinforced 
concrete  with  the  steps  moulded  on  top  thereof,  or 


STAIRWAYS  AND   FIRE   ESCAPES  527 

2.  The  girder  method,  in  which  inclined  girders  of  reinforced 
concrete  are  used  as  strings,  with  the  steps  formed  between. 

The  first  method  is  more  commonly  employed,  especially  for 
runs  not  over  8  to  10  feet  in  length  measured  on  the  slope.  Fig. 
175  *  illustrates  a  stair  of  this  type  used  in  the  Walter  Baker 


FIG.   175.  —  Concrete  Stairs,  Walter  Baker  Co.'s  Building,  Boston. 

Company's  Building,  Boston,  while  Fig.  176  also  illustrates  a 
slab-method  concrete  stairs,  as  used  in  the  United  States  Assay 
Office,  New  York.  For  such  examples,  a  slab  thickness  of  5 
inches  measured  at  the  foot  of  the  risers,  as  shown  in  Fig.  176, 
is  sufficient  for  a  run  of  half  the  height  of  an  ordinary  story. 
The  principal  reinforcement  consists  of  f-inch  round  rods  spaced 
6  inches  centers,  hooked  over  the  floor  and  landing  beams,  while 

*  Courtesy  of  Aberthaw  Construction  Company. 


528 


FIRE    PREVENTION   AND  TIRE    PROTECTION 


| -inch  round  cross-stiffening  rods  are  placed  18  inches  centers, 
wired  to  alternate  longitudinal  rods. 


ncrete 
.  of  Rod  to 
}f  Concrete 
^"0  Rods  G"O.C. 

TYPICAL  SECTION  THROUGH 
TREAD  AND  RISER 


3rd  Floo 
J  Up  30  Risers 
(down  22  Riser 


FIG.   176.  —  Concrete  Stairs,  U.  S.  Assay  Office,  N.  Y. 

In  the  girder  method,  two,  or  for  a  wide  stairway,  three  longi- 
tudinal girders  are  used.  These  are  proportioned  as  for  concrete 
beams,  with  longitudinal  reinforcing  rods  near  the  soffits,  while 
cross  reinforcement  is  placed  from  girder  to  girder  at  the  foot  of 
each  riser. 


FIRE  ESCAPES. 

Requirements.  —  By  fire  escapes  we  usually  mean  those 
auxiliary  means  of  emergency  egress  which  are  provided  in  a 
building  over  and  above  the  stairways  demanded  for  ordinary 
service.  Strictly  speaking,  fire  escapes  should  not  be  required 
in  intelligently  designed  fire-resisting  buildings,  as  the  ordinary 
means  of  egress  should  be  both  ample  and  safe  enough  to  suffice 
in  themselves  for  usual  service,  emergency  egress,  and  emer- 
gency access.  But,  as  has  been  previously  shown  (see  "Means 


STAIRWAYS   AND    FIRE    ESCAPES 


529 


of  Egress,"  page  300,  and  "Capacity  of  Stairs,"  page  509),  stair- 
ways are  generally  designed  without  much  reference  to  their 
value  as  emergency  exits,  and  with  even  less  reference  to  their 
capacity  under  emergency  conditions.  Hence  fire  escapes  be- 
come necessary  to  provide: 

1.  The  surplus  egress  capacity  required  over  and  above  the 
regular  stairways. 

2.  A  second  means  of  exit  where  only  one  stairway  is  pro- 
vided, and, 

3.  In  some  instances,  as  in  schools  and  warehouses,  etc.}  for 
the  access  of  firemen. 

Fire  escapes  may  be  located  either  on  the  interior  or  exterior 
of  a  building,  but  in  either  case,  three  requisites  are  necessary, 
viz.,  safety,  unobstructed  outlet,  and  access  to  roof. 

Interior  or  Tower  Fire  Escapes.  —  The  best  type  of  interior 
fire  escape  is  the  so-called  Philadelphia  Tower  Stairs.  These 


Interior  of 
Building 


Fire  Door 
Balcony,  Solid  Floor 


Opening  in  Face-Wall 
Extends  Floor  to  Ceiling 
Vestibule  Floor  of  Fireproof 
Construction 


FIG.  177.  —  Tower  Fire  Escape.        FIG.  178.  —  Tower  Fire  Escape,  Ves- 
tibule Type. 

consist  of  a  stairway  enclosed  by  walls  of  brick  or  other  approved 
fire-resisting  material,  and  isolated  from  the  several  floors  of  the 


530         FIRE   PREVENTION   AND   FIRE   PROTECTION 


building,  except  for  an  exterior  balcony  at  each  floor  level,  which 
forms  a  means  of  communication,  through  the  open  air,  between 
the  stair  tower  and  the  interior  of  building  (see  Fig.  177).  The 
balconies  should  have  solid  floors  and  substantial  railings,  and 
be  constructed  of  iron  throughout. 

Vestibule  Types.  —  Figs.  178  and  179  illustrate  improvements 
over  the  type  shown  in  Fig.  177,  in  that  interior  or  covered  vesti- 


Party 
Wall 


^^  MYindow 

Opening  in  Face-Wall 
Extends  Floor  to  Ceiling 
Vestibule  Floor  of  Fireproof  Construction 
Railing  at  Opening  as  Shown 

FIG.  179.  —  Tower  Fire  Escape,  Vestibule  Type  for  Two  Buildings. 

bules  take  the  place  of  the  exterior  balcony.  Fig.  178  shows  the 
vestibule  arrangement  as  ordinarily  used  for  a  single  building, 
while  Fig.  179  shows  the  arrangement  which  may  be  used  to  serve 
two  adjoining  buildings.  In  both  of  these,  the  vestibules  should 
be  of  thoroughly  fire-resisting  construction,  and  connected  to  the 
open  air  by  means  of  full  story-height  openings  in  the  exterior  wall. 
For  all  of  the  above  types,  the  stairs  should  be  of  approved 
fire-resisting  construction,  and  all  enclosing  walls  for  buildings 
hot  thoroughly  fire-resistive  should  be  built  solidly  of  brick  or 
concrete  from  foundations  to  at  least  3  feet  above  the  roof. 


STAIRWAYS  AND   FIRE   ESCAPES  531 

Advantages.  —  Tower  fire  escapes,  as  illustrated  above,  are 
decidedly  preferable  to  usual  exterior  fire  escapes,  for  many 
reasons.  They  have  no  direct  communication  with  the  building, 
hence  the  presence  of  flame  is  practically  impossible,  and  even 
danger  from  smoke  is  reduced  to  a  minimum.  In  the  vestibule 
types,  the  openings  in  the  exterior  wall  are  made  of  the  full  story 
height  from  floor  to  ceiling,  thus  permitting  the  escape  of  smoke 
to  the  open  air  instead  of  into  the  lower  height  stair  doors. 
The  stairs  run  to  the  ground  or  street  level,  and  may  be  used  as  or- 
dinary stairways,  thus  accustoming  the  occupants  of  the  building 
to  their  use;  and  they  are  immeasurably  safer  and  quicker  to 
use  than  exterior  balcony  and  ladder  fire  escapes.  The  vestibule 
types  require  somewhat  more  floor  space  than  the  balcon}'  type, 
but  the  former  are  less  liable  to  auto  exposure  from  windows 
below,  while  they  are  also  susceptible  to  better  architectural 
treatment. 

In  some  cases,  fire  tower  stairs,  either  one  or  more,  form  the 
only  means  of  communication  between  floors,  but  a  disadvantage 
in  such  use  lies  in  the  fact  that  operatives  or  others  must  then 
pass  into  the  open  air,  which,  in  severe  or  inclement  weather, 
entails  exposure  to  great  changes  in  temperature,  etc. 

In  the  report  of  the  New  York  Board  of  Fire  Underwriters  on 
the  Asch  Building  fire  (see  page  191),  the  more  general  use  of 
tower  fire  escapes  was  especially  recommended  for  factories,  etc. 

Hamburg  Tower  Stairs.  —  Fire  tower  stairs  with  balconies, 
so  arranged  as  to  serve  two  buildings,  are  used  in  the  newer  ware- 
houses of  the  Hamburg  Free  Port,  Hamburg,  Germany.  A 
floor  plan  of  two  of  these  buildings  is  shown  in  Fig.  180,  while 
the  arrangement  of  the  common  tower  stairs  and  balconies  is 
illustrated  in  larger  scale  in  Fig.  181. 

The,  arrangement  of  the  staircases  as  here  shown  is  due  to 
a  suggestion  of  the  chief  officer  of  the  Hamburg  Fire  Brigade.  .  .  . 
The  contrivance  of  this  circular  staircase  for  the  special  use  of 
firemen  is  certainly  a  very  clever  piece  of  planning.  It  suffices 
in  every  way  for  the  purposes  of  the  Fire  Brigade,  it  occupies  a 
minimum  space,  and  yet  in  no  way  adds  to  the  risk  of  spread. 
.  .  .  It  is  just  this  staircase  which  will  afford  particular  facilities 
for  the  firemen  when  wishing  to  attack  a  fire  in  any  one  building 
from  a  second  point.* 

*  See  "Fire-resisting  Warehouse  Construction  at  Hamburg,"  etc.,  Diary 
and  Notes  by  Edwin  O.  Sachs  and  Ellis  Marsland  in  the  Special  Commission 
which  visited  Berlin,  Hamburg  and  Hanover;  Journal  of  the  British  Fire 
Prevention  Committee  No.  V,  1910. 


532         FIRE   PREVENTION    AND   FIRE    PROTECTION 


Street 


FIG.   180.  —  Hamburg  Tower  Stairs  for  Warehouses. 


Fia,   181.  -r  Detail  of  Hamburg  Tower  Stairs. 


STAIRWAYS   AND    FIRE   ESCAPES  533 

Exterior  Fire  Escapes.  —  As  usually  installed,  exterior  fire 
escapes  are  inefficient  to  a  degree.  Their  use  should  be  generally 
discouraged,  and,  indeed,  prohibited  when  passing  windows, 
unless  the  latter  are  made  of  metallic  frames  and  wire  glass. 

Numerous  instances  have  been  recorded  of  the  utter  inade- 
quacy of  the  usual  installations,  prominent  examples  being  the 
Asch  Building  fire,  previously  described  in  Chapter  VI,  and  the 
Newark,  N.  J.,  factory  fire  of  November  26,  1910,  in  which  25 
lives  were  lost. 

Ordinary  Type.  —  The  design  and  construction  of  exterior  fire 
escapes  of  the  ordinary  balcony  and  step  ladder  type  are  regu- 
lated as  to  minimum  requirements  by  the  local  or  state  laws  in 
force;  but  such  laws  are  often  either  vague  or  totally  inadequate, 
especially  in  the  matter  of  a  serviceable  connection  between  the 
lowest  balcony  and  the  ground.  The  minimum  requirements 
of  the  City  of  Boston  Building  Department,  which  are  better 
than  the  average,  are  indicated  in  Fig.  182;  but  the  widths  of 
stairs  and  balconies,  the  general  arrangement  and  the  method 
of  securing  outlet  to  street  or  other  level,  all  rest  with  the  Build- 
ing Commissioner  for  final  approval. 

Vertical  ladders,  instead  of  stairs  as  illustrated  above,  should 
never  be  permitted.  Some  localities  allow  vertical  ladders, 
especially  when  outside  standpipes  are  also  installed  as  a  part 
of  the  fire  escape  equipment.  But,  while  frequently  useful  to 
firemen  (unless  the  hose  connections  to  the  standpipe  are  rusted 
fast,  as  is  liable  to  be  the  case),  such  vertical  ladders  are  totally 
unfitted  for  use  by  women  or  children. 

Disadvantages.  —  At  the  best,  light  iron  fire  escapes  are  not 
calculated  to  inspire  confidence  in  the  user  under  even  normal 
conditions,  much  less  under  conditions  of  panic  and  danger; 
they  are  not  generally  used  except  in  event  of  fire,  and  hence  are 
not  to  be  compared  in  efficiency  with  regular  means  of  exit; 
they  are  unsightly,  thus  influencing  architect  or  owner  to  place 
them  in  inconspicuous  locations,  rather  than  where  most  ser- 
viceable; and,  over  and  above  all  of  these  disadvantages,  they 
are  usually  of  inadequate  capacity  for  many  people,  inaccessible, 
unsafe  as  regards  their  passing  unprotected  windows,  and  often 
without  adequate  outlet. 

Capacity.  —  The  often  inadequate  capacity  of  stairs  has  pre- 
viously been  pointed  out,  but  this  question  becomes  of  even 
more  importance  as  regards  fire  escapes  when  other  means  are 


534         FIRE   PREVENTION   AND    FIRE   PROTECTION 

{2L  Post 


Not  over  9  Rise 
;Not  less  than  7'Tread 
6-8  Channel  Strings 


Clear 
FIG.   182.  —  Exterior  Fire  Escape,  Boston  Requirements. 

insufficient.  The  usual  " zig-zag"  installation,  as  shown  in 
Fig.  182.  presents  difficulties  which  need  not  be  enlarged  upon. 
The  influx  of  people  upon  several  balconies  at  one  and  the  same 
time,  and  the  difficulty  of  frequent  turnings  and  crowding 
through  the  narrow  portions  of  balconies,  would  soon  result  in 
catastrophe.  For  this  reason,  "the  straight-run"  fire  escape 
is  greatly  to  be  preferred,  that  is,  continuous  runs,  without  any 
turns  whatever,  as  shown  in  Fig.  296. 

The  1911  law  of  the  state  of  New  Jersey  regarding  means  of 
emergency  egress  for  factories,  etc.,  states  that  fire  escapes 
"shall  be,  where  practicable,  on  the  straight-run  type";  also,  as 
showing  that  both  the  limitation  of  occupancy  and  the  capacity  of 
means  of  egress  are  gradually  receiving  recognition,  the  following : 

With  such  plans  and  specifications  (for  new  or  remodeled 
buildings  more  than  two  stories  high  devoted  to  factory  purposes) 


STAIRWAYS  AND    FIRE   ESCAPES  535 

shall  be  submitted  an  estimated  number  of  employees  to  be  en- 
gaged upon  each  story  or  separated  subdivision  of  any  story  of 
the  proposed  building.  .  .  .  All  installation  of  fire  escapes  or 
stairways  shall  be  made  with  reference  to  the  maximum  number 
of  persons  to  be  employed  upon  each  story  of  any  building  or 
separated  subdivision  thereof,  a  statement  of  which  number  shall 
be  posted  by  the  owner  upon  the  wall  of  each  story  or  separated 
subdivision  thereof,  so  as  to  be  visible  at  all  times.  Under  no 
circumstances  shall  this  number,  when  once  ascertained,  and 
installation  of  fire  escapes  and  stairways  be  made  with  reference 
thereto,  be  exceeded,  except  by  permission  of  the  Commissioner. 

Inaccessibility  usually  results  from  the  fact  that  access  to  the 
balconies  must  be  gained  by  climbing  out  of  windows.  In  build- 
ings where  many  people  are  dependent  upon  the  use  of  exterior 
fire  escapes,  as  in  factories,  etc.,  metal-covered  doors  opening 
out,  in  metal-covered  frames,  with  sills  flush  with  the  floor  level, 
should  be  required  by  law  at  all  balconies. 

Unprotected  Windows.  —  One  of  the  greatest  objections  to  the 
ordinary  fire  escape  installation  is  the  fact  that  the  balconies  are 
apt  to  be  more  or  less  blocked  by  fire  shutters,  or  else  both  bal- 
conies and  stairs  are  wholly  unprotected  from  window  openings. 
Thus  every  unshuttered  window  below  any  balcony  or  stairs 
forms  a  distinct  menace  as  to  either  cutting  off  escape  by  flame, 
or  wrecking  the  light  iron  construction  as  was  exemplified  in  the 
Asch  Building  fire.  Theater  fire  escapes  are  usually  required 
to  be  covered,  partly  as  protection  against  ice  and  partly  to  pre- 
vent the  uprush  of  flames  from  doors  or  windows  to  fire  escapes 
or  openings  above ;  but  as  such  coverings  are  often  impracticable, 
and  as  they  still  do  not  protect  any  fire  escape  from  the  windows 
opening  directly  thereon,  all  windows  exposing  either  balconies 
or  stairs  should  be  made  of  metallic  frames  and  wire  glass. 

Outlet.  —^  Some  form  of  movable  ladder  or  stairs  is  necessary 
to  connect  the  lowest  balcony  to  the  street,  ground,  or  other 
secure  level,  —  first,  because  access  to  the  building  by  means  of 
such  stairs  or  ladder  must  be  guarded  against,  and  second,  be- 
cause, if  lowered  permanently,  the  stairs  or  ladder  would  gen- 
erally be  in  the  way  of  traffic. 

Means  by  which  such  outlet  may  be  obtained  include: 

1.  Drop  ladder,  usually  light  and  portable,  so  that  it  may  be 
hooked  over  the  floor  or  railing  of  the  balcony  above  the  lowest. 
In  some  cases  vertical  guides  are  placed  at  the  upper  portion  of 
such  a  ladder,  to  direct  its  course,  and  to  insure  its  not  being 


536 


FIRE    PREVENTION   AND    FIRE    PROTECTION 


dropped  entirely;  but  of  whatever  form,  the  drop  ladder  means 
of  outlet  is  inadequate  and  even  dangerous. 


FIG.   183.  —  Circular  Stair  Fire  Escape,  Pemberton  Building,  Boston. 

2.  Counterbalanced  drop  ladder,  same  as  above,  except  that 
it  is  counterbalanced  by  means  of  a  wire  rope  passing  over  an 
overhead  pulley,  with  suspended  counterbalance.     This  form  is 
unstable,  and  not  suited  for  use  by  women  or  children. 

3.  Folding  or  collapsible  ladder,  in  which  the  rungs  and  the 
outer  upright  fold  against  or  into  the  inner  upright,  which  is 


STAIRWAYS   AND    FIRE    ESCAPES  537 

securely  fastened  to  the  wall.  The  same  objections  hold  as  in 
the  previous  types. 

4.  Counterbalanced  stairs,  wherein  the  lowest  run  of  stairs  is 
counterbalanced  about  a  pin  joint.  The  extension  of  the  strings 
(beyond  the  joint),  with  cast-iron  counterweights  secured  be- 
tween, is  made  to  counterbalance  exactly  the  weight  of  the  stairs 
in  front  of  the  joint.  For  short  drops  the  pin  joint  may  be  made 
at  about  the  balcony  level,  but  for  longer  drops,  where  the 
weight  of  stairs  would  be  too  great  to  counterbalance  properly, 
the  pin  joint  is  placed  at  the  foot  of  a  short  fixed  run  which  is 
adequately  braced  and  supported. 

This  type  is  the  only  efficient  means  now  in  use  of  securing  a 
proper  outlet  for  a  fire  escape  to  the  ground  or  street. 

Circular  Fire  Escapes.  —  Where  something  better  or  more 
architectural  than  the  ordinary  zig-zag  fire  escape  is  desired, 
circular  stairs  may  be  employed.  Fig.  183  illustrates  a  very 
pleasing  and  efficient  arrangement,  as  used  on  the  rear  of  the 
Pemberton  Building,  Boston,  Fehmer  and  Page,  architects.  It 
will  be  noted  that  the  stairs  are  fairly  well  protected  by  a  blank 
wall  area,  so  that  when  people  have  once  gained  the  stairs, 
no  windows  are  passed.  The  principal  disadvantage  to  this  ar- 
rangement is  the  dizziness  which  may  result  from  descending 
many  flights  rapidly.  To  prevent  pitching  forward  and  over 
the  stair  railing  from  dizziness,  such  stairs  are  frequently  enclosed 
by  means  of  wire  netting,  or  rods  at  intervals  of  4  to  6  inches, 
run  from  the  top  of  railing  to  the  under  side  of  the  treads 
above. 

The  Kirker-Bender  Slide  Fire  Escape  *  combines  maximum 
safety  and  capacity  to  a  far  greater  degree  than  any  other  form 
of  fire  escape  yet  invented.  Its  use  is  particularly  adapted  to 
schools,  ,asylums,  etc.,  where  many  children  must  be  cared  for, 
or  to  buildings  housing  many  women.  The  arrangement,  as 
shown  in  Fig.  184,  which  illustrates  the  Girls'  High  School  at 
Louisville,  Ky.,  consists  of  an  enclosed  helical  slide  which  is 
built  around  a  central  core  or  standpipe.  Entrance  doors  are 
provided  at  the  different  floors  and  at  roof.  These  are  made  in 
two  leaves  and  are  so  hung  as  to  open  inwards  without  extending 
over  the  spiral  slide.  They  are  held  closed  by  a  spring  only,  so 
as  automatically  to  keep  out  water,  smoke  or  flame.  The  exit 
doors  at  the  bottom  are  also  made  in  two  leaves  which  are 
*  Made  by  the  Dow  Wire  and  Iron  Works,  Louisville,  Ky. 


538 


FIRE    PREVENTION    AND    FIRE    PROTECTION 


immediately   opened   by    contact   or   pressure   of    any   sliding 
weight,  as  of  a  person. 

The  tubes  are  usually  made  6  feet  in  diameter,  and  are  placed 
between  windows  so  as  not  to  obstruct  light  or  air.  Iron  bal- 
conies connect  one  window  or  door  per  floor  with  entrances.  In 
Fig.  184,  entrances  occur  at  the  second,  third  and  fourth  floors, 


FIG.   184.  —  "Kirker-Bender"  Patent  Slide  Fire  Escape. 


that  at  the  third  being  hidden  by  the  tube.  The  slide  is  wide 
enough  to  permit  of  two  persons  sliding  down  side  by  side,  and 
the  capacity  is  variously  estimated  at  from  125  to  250  persons 
per  minute. 

The  central  core  of  the  tube  is  usually  arranged  for  service  as 
a  standpipe,  with  fire-engine  connection  at  the  ground,  and  hose 


STAIRWAYS   AND   FIRE   ESCAPES  539 

connections  at  each  floor  and  roof.     A  ladder  for  use  of  firemen 
may  also  be  placed  on  the  exterior  of  the  tube,  if  desired. 

Access  to  Roof.  —  All  fire  stairways  or  fire  escapes  should 
provide  access  to  the  roof  of  building,  especially  where  adjoining 
structures  are  of  about  the  same  height. 

The  best  means  of  escape  after  the  staircase  is  by  way  of 
the  roof.  A  good  flight  of  stairs  should  be  provided  to  a  roof 
door  which  should  have  an  automatic  fastening.  In  the  Cripple- 
gate  fire  the  upper  two  stories  were  occupied  by  seventy  or  eighty 
workgirls,  and  the  owner  willingly  put  a  proper  door  to  lead 
onto  the  roof.  By  this  route  he  and  they  got  away,  but  without 
it  they  must  all  have  perished.  ...  As  workwomen  are  often 
accommodated  by  hundreds  on  top  stories,  this  is  a  useful  lesson 
in  the  construction  of  means  of  escape.* 

*  "Lessons  from  Fire  and  Panic,"  by  Thomas  Blashill,  British  Fire  Preven- 
tion Committee's  "Red  Book,"  No.  9,  page  22. 


CHAPTER  XVI 

ELEVATOR  SHAFTS  AND  ENCLOSURES.    PIPE  SHAFTS, 
CHUTES,  ETC.  " 

Passenger  Elevator  Enclosures.  —  Passenger  elevators  are 
usually  confined  to  those  classes  of  buildings  in  which  archi- 
tectural considerations  are  of  decided  importance  to  owners  or 
tenants,  and  hence,  as  in  the  case  of  main  stairways,  the  isolation 
of  the  elevators  within  absolutely  fire-resisting  shafts  is  still  often 
considered  as  more  or  less  of  a  theoretical  desirability  which 
must  give  way  to  the  more  practical  or  commercial  considerations 
of  appearance  and  prevalent  custom. 

The  vital  importance  of  cutting  off  such  shafts  has  previously 
been  pointed  out.  See  "  Vertical  Openings,"  page  312. 

San  Francisco's  experience  indicates  that  wells  and  elevator 
shafts,  running  up  through  many  stories,  should  be  guarded  by 
brick  or  reinforced-concrete  walls,  fitted  with  double  metal 
rolling  doors,  bolted  to  the  walls  to  allow  for  expansion,  or  with 
automatic  sliding  doors  and  wire  glass  partitions.  There  was 
little  or  no  provision  for  cutting  off  the  draught  of  air  that  will 
ascend  through  such  a  shaft  during  a  fire,  and  great  destruction 
resulted  in  consequence.* 

Types  of  enclosures  in  common  practice  include  open  grille 
work,  solid  masonry  or  metal  lath  and  plaster  partitions,  and 
metal  and  wire  glass  enclosures. 

Open  Grille  Enclosures.  —  The  present  type  of  open  grille- 
work  elevator  enclosure  has  been  brought  to  a  high  point  of 
perfection  by  American  architects  and  manufacturers,  and  in 
many  important  buildings  this  feature  of  interior  finish  consti- 
tutes one  of  the  principal  sources  of  architectural  embellishment. 

Architects  and  owners  have,  therefore,  been  loth  to  sacrifice 
such  conventional  architectural  treatments  for  what  many  con- 
sider to  be  undue  precaution  against  an  improbable  danger,  pre- 

*  See  United  States  Geological  Survey  Bulletin  No.  324,  "  The  San  Francisco 
Earthquake  and  Fire."  Report  by  Prof.  Frank  SouIS. 

540 


ELEVATOR  SHAFTS  AND  ENCLOSURES      541 

ferring  to  retain  architectural  appearance  instead  of  insuring 
efficiency  against  a  risk  which  is  seemingly  always  considered 
remote. 

One  of  the  best-known  office  buildings  in  New  York  City  has 
only  one  stairway,  located  immediately  adjacent  to  the  six 
elevator  shafts,  three  on  either  side  of  a  central  corridor.  All 
of  these  are  unenclosed,  and  open  to  all  floors  of  the  building, 
save  by  open  grille  work  at  the  elevator  fronts.  A  serious  fire 
on  any  floor  would  render  escape  of  the  occupants  from  the  upper 
floors  practically  impossible,  as  flames  or  smoke,  or  both,  would 
make  both  stair  and  elevators  impassable.  These  features 
should  have  been  more  intelligently  planned,  but  even  located 
as  at  present,  the  dangerous  conditions  existing  reflect  seriously 
upon  the  owners  and  the  municipal  authorities.  Unfortunately, 
this  case  is  only  typical,  and  not  exceptional. 

Solid  Enclosure  Walls.  —  Before  the  advent  of  wire  glass, 
there  was  no  alternative  between  an  open  grille  enclosure  and  a 
solid  wall  of  brick,  hollow  tile  or  metal  lath  and  plaster.  The 
solid  type  of  enclosure,  while  common  for  freight  elevator  shafts, 
is  only  occasionally  used  to  surround  passenger  elevators,  prin- 
cipally on  account  of  appearance,  as  already  noted,  and  on 
account  of  the  difficulty  of  lighting  such  shafts.  For,  unless 
provided  with  windows  at  the  rear,  wellrooms  surrounded  by 
solid  enclosures  are  apt  to  be  dark  and  generally  uninviting,  and 
dependent  upon  artificial  light  in  the  elevator  cars,  even  though 
the  shafts  are  lined  with  white-enameled  brick  or  tile,  as  is  often 
done. 

From  the  standpoint  of  fire  protection,  however,  no  type  of 
elevator  enclosure  is  comparable  to  a  solid  brick  or  concrete  wall. 
Rigidity  and  stability  are  especially  desirable.*  Doors  suitable 
for  use  with  such  enclosures  have  been  described  in  Chapter  XIV 
(see  especially  Figs.  144  and  145) ;  but  solid  doors  are  open  to  the 
objection  that  the  car  operator  cannot  see  passengers  waiting  at 
the  floor  levels,  while  small  observation  holes  of  glass  in  the 
doors,  or  even  glass  upper  panels,  do  not  give  the  elevator  opera- 
tors that  quick  and  complete  view  of  waiting  passengers  which 
insures  quick  and  safe  service.  Also,  customers,  tenants  and 
the  public  generally  like  to  obtain  a  full  view  of  the  cars  as  they 
ascend  and  descend  the  shafts.  Indicators  or  flashlights  may 
designate  the  floors  at  which  the  various  elevator  cars  are  passing 

*  Compare  with  paragraph  "Enclosing  Partitions,"  Chapter  XV,  page  505. 


542 


FIRE    PREVENTION    AND    FIRE   PROTECTION 


or  stopping,  but  the  eye  grasps  the  location  of  the  car  itself,  if 

within  sight,  or  even  the  direc- 
tion in  which  the  cables  or  plun- 
gers are  traveling,  more  quickly 
than  the  index  arm  of  an  indi- 
cator. 

Metal  and  Wire  Glass  En- 
closures. —  The  invention  and 
introduction  of  wire  glass,  how- 
ever, has  solved  many  difficul- 
ties in  connection  with  passenger 
elevator  enclosures  in  a  most 
acceptable  manner.  For,  al- 
though by  no  means  as  efficient 
against  fire  as  a  brick  or  con- 
crete wall,  and  although  of  little 
avail  as  far  as  preventing  the 
radiation  of  intense  direct  heat 
is  concerned,  still  its  efficiency 
in  the  walls  of  a  vertical  shaft 
is  sufficiently  high  to  answer 
every  reasonable  requirement, 
and  its  use  still  makes  possible 
the  continuance  of  the  conven- 
tional grille  enclosure,  or  at  least 
an  adaptation  which  is  suscepti- 
ble of  highly  attractive  archi- 
tectural treatment. 

As  far  as  the  fire-resistance  of  ' 
wire  glass  in  elevator  fronts  is 
concerned,  it  is  probable  that 
its  use  in  this  manner  is  one  of 
the  most  satisfactory  adapta- 
tions yet  found  for  this  material, 
— even  more  satisfactory  than 
when  used  for  windows  or  parti- 
tions. For  in  these  latter  cases 
the  wire  glass  is  called  upon  not 
only  to  prevent  the  passage  of 
flame,  but  to  prevent  the  passage  of  direct  heat  severe  enough 
to  ignite  trim  or  contents  beyond  the  window  or  partition;  while 


FIG.  '185.  —  Wire  Glass  Elevator 
Door,  Warren  &  Wetmore,  Archi- 
tects. 


ELEVATOR  SHAFTS  AND  ENCLOSURES      543 

in  elevator  shaft  enclosures,  even  though  the  front  at  one  floor 
should  fail  under  a  particularly  severe  fire  test,  as  would  be  more 
than  likely  through  the  buckling  or  destruction  of  the  metal  or 
metal-covered  doors,  the  usual  rise  of  heated  air  in  an  elevator 
shaft,  and  the  added  tendency  in  this  respect  from  the  fire  raging 
at  any  floor,  would  tend  to  draw  the  flame,  and  hence  the  severe 
heat,  upward  past  the  successive  stories  and  vent  it  at  the  roof. 


FIG.  186.  —  First  Story  Elevator  Fronts,  West  St.  Building,  N.  Y.,  Cass  Gilbert, 
Architect. 

The  past  several  years  have  witnessed  the  installation  of  many 
wire  glass  elevator  enclosures,  especially  in  office  buildings,  hotels 
-and  apartment  houses,  and  this  type  may  now  fairly  be  considered 
the  standard  in  this  type  of  structures. 


544          FIRE    PREVENTION    AND    FIRE    PROTECTION 

All  of  the  different  types  of  wire  glass  have  been  employed  for 
this  purpose  —  rough,  ribbed,  figured  and  polished-plate  wire 
glass,  but  the  latter  variety  is  generally  employed  on  passenger 


FIG.  187.  —  Upper  Story  Elevator  Fronts,  West  St.  Building,  N.  Y., 
Cass  Gilbert,  Architect. 

elevator  fronts,  at  least  for  the  doors.  Fig.  185  shows  a  single 
elevator  front  door,  of  iron  framework,  with  a  single  light  of 
polished-plate  wire  glass. 


ELEVATOR  SHAFTS  AND  ENCLOSURES      545 

A  most  pleasing  architectural  treatment  of  the  wire  glass 
elevator  enclosure  is  to  be  seen  in  the  West  Street  Building,  New 
York  City,  Cass  Gilbert,  architect  —  where  the  Gothic  style  of 
the  building  is  adapted  to  the  elevator  fronts.  Fig.  186*  illus- 
trates the  passenger  elevator  enclosure  in  the  first  story,  while 
Fig.  187  *  illustrates  the  fronts  in  the  upper  stories.  In  the  latter 
it  will  be  noticed  that  plate  wire  glass  is  used  only  in  the  large 
panels  of  the  doors. 

Freight  Elevator  Enclosures.  —  The  question  of  fronts  or 
enclosures  for  freight  elevators  is  a  comparatively  simple  one, 
as  such  elevators  are  usually  placed  in  rear  hallways,  or  in  incon- 
spicuous locations,  where  solid  wall  enclosures  are  not  objection- 
able. If  brick  walls  are  used  to  give  the  utmost  efficiency,  cast- 
iron,  channel-iron  or  angle-iron  door  frames  are  usually  employed, 
with  either  wrought-  or  cast-iron  sills,  as  described  in  Chapter 
XIV.  The  doors  may  be  sliding  or  hinged,  of  tin-covered  wood, 
or  copper  or  sheet-metal  covered.  In  very  wide  openings,  as 
for  instance  in  storage  warehouses  or  in  stores  where  furniture 
must  be  handled  by  elevator,  the  doors  are  often  made  double- 
leaf,  so  that  each  opening  will  have  two  double-leaf  doors  folding 
back  against  the  walls.  If  some  attention  to  architectural  effect 
is  required,  the  frames  or  jambs  may  be  made  of  moulded  cast- 
iron  or  pressed  sheet-metal  over  wood.  See  also  "  Freight  Eleva- 
tor Enclosure  Doors/'  page  499. 

Window  Protection  Rods.  —  All  windows  opening  into  ele- 
vator shafts  should  be  provided  with  protection  rods  running 
from  sill  to  head,  securely  fastened  to  masonry  or  metal  work  if 
practicable,  rods  to  be  spaced  about  6  to  8  inches  on  centers. 
These  are  for  the  purpose  of  warning  firemen  against  stepping 
into  such  windows  from  ladders. 

Dumb  Waiter  Enclosures.  —  Dumb  waiters,  when  used  in 
fire-resisting  buildings,  should  always  be  enclosed  by  solid  walls. 
The  doors  and  door  frames  may  be  as  above  described  for  freight 
elevators,  except  that  the  openings  are  usually  smaller,  and  placed 
some  3  feet  above  the  floor  to  give  easy  access  to  the  lift.  The 
doors  should  preferably  be  automatic. 

Pipe-  and  Vent- Shafts.  —  Pipe-  and  vent-shafts,  from  their 
nature  of  service,  are  necessarily  enclosed  by  solid  walls  of  brick 
or  terra-cotta,  so  that  the  only  care  necessary  in  these  vertical 
openings  is  to  see  that  all  horizontal  communications  between  the 

*  Courtesy  of  Hecla  Iron  Works,  Brooklyn,  N.  Y. 


546 


FIRE    PREVENTION   AND    FIRE    PROTECTION 


shafts  and  the  balance  of  the  building  are  completely  cut  off,  and 
that  some  form  of  fire-resisting  doors  and  door  frames  is  used. 
The  frames  should  preferably  be  of  metal,  although  metal-covered 
wood  is  often  used.  Wood  doors  covered  with  tin,  copper  or 
sheet-metal  are  usual,  but  for  the  comparatively  small  openings 
into  such  shafts  a  paneled  cast-iron  door  is  undoubtedly  the  best, 
and  such  doors  can  be  made  very  pleasing  in  appearance. 

See  also  " Installation  of  Mechanical  Features,"  page  314. 

Waste-paper  Chutes.  —  In  large  department  stores,  etc., 
the  proper  disposal  of  waste  paper,  excelsior,  and  other  materials 


Fia.  188.  —  Waste-paper  Chute. 

used  for  wrapping  and  packing  becomes  a  question  of  consider- 
able importance.  To  accomplish  this  safely,  waste-paper  chutes 
are  now  installed  in  most  large  buildings  of  this  character.  The 
first  requisite  is  a  special  brick-walled  shaft,  continuous  from  cel- 
lar to  roof,  within  which,  at  about  2  ft.  8  ins.  above  each  floor 
level,  is  placed  a  box  usually  made  of  No.  12  sheet-iron.  These 
boxes  are  of  the  full  depth  of  the  shaft,  while  occupying  only 


ELEVATOR  SHAFTS  AND  ENCLOSURES      547 

about  one-half  the  width  of  shaft,  as  shown  in  Fig.  188.  Each 
box  has  a  counterweighted  tip  bottom,  which,  when  dropped, 
empties  the  contents  of  the  box  upon  an  inclined  ledge,  placed 
over  the  box  below,  thus  deflecting  the  waste  material  to  the 
open  shaft  where  it  drops  to  the  basement.  Access  to  each  box 
is  had  by  means  of  an  iron  door,  placed  in  an  iron  frame  in  the 
wall,  as  indicated  by  the  double  dotted  lines  in  Fig.  188. 

The  possibility  of  fire  within  the  shaft,  and  the  resultant  com- 
munication of  same  to  a  floor  by  the  opening  of  the  door  in  the 
wall,  has  been  provided  against  in  that  the  door  can  only  be 
opened  when  the  tip  bottom  is  up  or  closed,  thus  preventing 
communication  between  the  open  shaft  and  the  room.  This  is 
accomplished  by  means  of  a  lever  handle  (placed  on  the  face  of 
wall  in  the  room),  which  operates  the  tip  bottom.  To  drop  the 
bottom  of  the  box,  this  lever  handle  must  be  raised,  and  this 
cannot  be  done  when  the  door  is  either  wholly  or  partly  open. 

For  the  still  further  disposal  of  waste  paper,  etc.,  in  large 
establishments,  special  paper-burning  grates  are  sometimes  in- 
stalled at  the  base  of  smoke  flue,  or  an  incinerator  chamber  may 
be  used. 

Package  Chutes  are  often  installed  for  the  delivery  of  pack- 
ages from  various  floors  of  department  stores  to  sorting  and 
packing  tables  in  the  basement.  They  consist  of  a  helical  plate- 
iron  chute,  within  a  cylindrical  iron  enclosure.  They  should 
invariably  be  placed  within  masonry  shafts,  with  small  doors 
opening  into  the  chutes  at  the  various  stories, 


PART   IY. 

FIRE-RESISTING   CONSTRUCTION. 


CHAPTER  XVII. 

TERRA-COTTA    FLOORS,*     GIRDER     PROTECTIONS, 

ETC. 

Terra-cotta  floor  arches  are  made  of  either  " porous,"  l ' semi- 
porous  "  or  "hard  burned"  terra  cotta.  The  manufacture  and 
characteristics  of  these  different  grades  of  terra-cotta  and  their 
fire-resisting  qualities  have  been  described  in  Chapter  VII.  The 
various  types  of  terra-cotta  floor  arches  employed  in  present 
practice,  their  safe  loads,  methods  of  setting,  fire  tests,  etc.,  will 
now  be  taken  up. 

Construction  of  Flat  Arches.  —  Flat  terra-cotta  or  "hollow- 
tile"  arches  are  made  up  of  two  "skews"  or  "skewbacks"  which 
rest  against  the  beam  webs  and  which  fit  against  or  around  the 
lower  flanges  of  the  beams,  — one  "key"  or  center  block,  — and 
" lengtheners "  (sometimes  called  "fillers,"  " part-fillers  "  or  "in- 
termediates") sufficient  in  number  to  fill  the  spaces  between  the 
skewbacks  and  the  key.  These  blocks  are  made  in  a  great 
variety  of  shapes,  sizes  and  weights  by  the  larger  manufacturers, 
but  the  principal  types  will  be  shown  in  the  following  illustrations. 

In  scheduling  arch  blocks,  the  dimensions  are  usually  written  : 
width  X  depth  X  length.  Thus,  an  8  X  10  X  12  lengthener 
would  mean  one  in  which  the  width  in  direction  parallel  to 
beams  was  8  inches,  the  depth  of  arch  or  depth  of  block  10  inches, 
and  the  length  of  block,  measured  at  right  angles  to  the  beams, 
12  inches. 

Side-construction  Arches.  —  In  this  form  of  arch  the  voids 
or  cells  in  the  blocks  run  parallel  to  the  supporting  beams. 
Fig.  189  illustrates  a  typical  side  construction  arch  as  commonly 
used  for  short  span  and  shallow  depth.  Fig.  190  shows  a  deeper 
and  heavier  arch  for  wider  span. 

Side-construction  skews  may  be  made  either  "plain"  (that 
is,  with  no  provision  for  the  protection  of  the  beam  flange), 

*  For  the  special  Guastavino  terra-cotta  floor  and  dome  construction,  see 
Chapter  XI,  page  328. 

551 


552         FIRE   PREVENTION   AND   FIRE   PROTECTION 

" lipped"  (having  protection  lips  moulded  on  as  a  portion  of  the 
skew,  as  shown  in  Fig.  190)  or  " soffit"  skews  (where  a  bevel 
is  provided  at  the  bottom  of  the  skew  to  hold  the  separate  soffit 
tile  under  the  beam,  as  shown  in  Fig.  189). 


FIG.   189.  —  Side-construction  Hollow  Tile  Flat  Arch. 

Plain  skews  are  sometimes  employed  where  the  arch  is  carried 
on  a  shelf  angle  rivetted  to  the  beam,  in  which  case  separate 
shoe  tile,  etc.,  are  placed  below  the  skews  to  protect  the  lower 
portions  of  the  beams.  Lipped  skewbacks  have  been  extensively 


FIG.   190.  —  Side-construction  Hollow  Tile  Flat  Arch. 

used  in  the  past  in  side-construction  arches,  but  in  manufacturing 
such  blocks  with  the  beam  protections  burned  on,  much  difficulty 
was  experienced  in  keeping  the  projecting  flanges  straight,  as  the 
warping  during  drying  and  burning  often  so  deformed  the  lips 
as  to  prevent  the  skews  from  being  placed  around  the  beam 
flanges  without  breaking  the  lip  from  the  skew.  Much  breakage 
of  the  lips  also  occurred  from  tightening  up  the  centers  of  the 
arches  during  erection,  and  in  shipment.  These  objections  were 


TERRA-COTTA   FLOORS,  GIRDER   PROTECTIONS,  ETC.       553 

so  serious  that  most  manufacturers  have  now  abandoned  the 
lipped  skew  in  favor  of  the  soffit  skew  with  the  separate  soffit  tile. 
In  a  flat  hollow-tile  arch  the  line  of  maximum  thrust  will  be 
near  the  top  of  the  key  and  near  the  bottoms  of  the  skews. 
Hence,  theoretically,  the  horizontal  webs  or  interior  partitions 
of  the  blocks  should  approximately  follow  this  line,  as  shown  in 
Fig.  191.  This,  however,  has  been  found  to  be  commercially 


FIG.  191.  —  Side-construction  Arch,  Radial  Joints  and  Arched  Webs. 

impracticable  on  account  of  the  many  different  types  of  blocks 
required  for  a  single  arch,  and  for  varying  spans.  This  would 
add  materially  to  the  cost  of  manufacture  and  to  the  cost  of 
setting.  Hence  the  lengtheners  are  always  made  of  the  same 
form,  but  in  order  to  develop  the  full  strength  of  the  arch  under 
even  this  practice,  the  skews  should  be  of  heavy  outer  shells  and 
interior  webs,  and  the  latter  should  invariably  include  one  across 
the  block  about  on  a  line  with  the  lower  flange  of  the  beam. 
The  omission  of  bottom  webs  in  skews  has  been  responsible,  in 
some  instances,  for  the  collapse  of  arches. 

Another  theoretical  point  illustrated  in  Fig.  191  is  the  use  of 
radial  joints,  or  joints  which  would  meet  at  a  common  center  if 
prolonged  below  the  arch.  Such  practice  would  undoubtedly 
make  a  better  and  stronger  arch,  but,  as  in  the  case  of  arched 
webs,  the  added  expense  of  making  and  handling  such  a  variety 
of  blocks  would  much  more  than  offset  any  compensating  ad- 
vantages in  strength. 

One  great  advantage  of  the  side-construction  arch  is  the  possi- 
bility of  breaking  joints  between  the  blocks,  as  shown  in  Fig.  189, 
whereby  the  strength  of  the  arch  is  not  seriously  affected  by  the 
possible  breaking  of  any  one  block. 

Figs.  189  and  190  show  the  blocks  grooved  or  "scored"  on  all 
sides  to  provide  a  key  for  the  mortar  in  the  joints,  and  for  the 
plastering. 

The  various  depths  of  arch  blocks,  weights  per  square  foot  of 
arches,  and  permissible  spans  for  standard  side-construction 
arches  are  as  follows ; 


554 


FIRE    PREVENTION    AND    FIRE    PROTECTION 


Spans  allowable  between  I-beams. 

Depth  of  arch, 
inches. 

Weight,  pounds  per 
square  foot. 

Arch  set  flat, 
feet  and  inches. 

Set  with  slight  cam- 
ber, 
feet  and  inches. 

6 

24  to  26 

4-0 

4-6 

7 

26  to  28 

4-6 

5-6 

8 

27  to  32 

5-0 

6-0 

9 

29  to  36 

5-6 

7-0 

10 

33  to  38 

6-6 

7-6 

12 

37  to  44 

7-0 

8-6 

Note.  —  The  heavier  weights  are  the  ones  commonly  used. 

The  following  tables*  give  the  safe  loads  for  various  depths 
and  spans  of  side-construction  arches. 

*  As  used  by  the  National  Fire  Proofing  Company. 


TERRA-COTTA   FLOORS,  GIRDER   PROTECTIONS,  ETC.       555 
SAFE  LOADS— SIDE-CONSTRUCTION  FLAT  ARCHES. 

Material,  semi-porous.  Blocks  with  webs  f  of  an  inch  thick.  Factor  of  safety  7. 

Light  Sections. 


6,  7,  8  and  9  inches.          10  and  12  inches.  15  inches. 

Note.  —  In  the  following  table  the  weight  of  the  arch  blocks  has  been  deducted 
from  the  safe  load.  The  weight  of  cinder-fill,  flooring  and  plastering  must  be 
deducted  to  obtain  net  live  load. 

The  widest  span  permissible  for  any  arch  is  indicated  by  cross  rule  in  the 
column.  Beyond  this  span  it  should  only  be  used  as  a  ceiling  arch. 


6-inch 

7-inch 

8-inch 

9-inch 

10-inch 

12-inch 

15-inch 

arch. 

arch. 

arch. 

arch. 

arch. 

arch. 

arch. 

Weight  of 

arches,  pounds 

24 

25.5 

27 

29 

33.5 

37 

46 

per  square  foot. 

Cross-sectional 

area  of  blocks, 

22.5 

22.5 

22.5 

22.5 

30 

30 

37.5 

square  inches. 

Span  in  feet  and 
inches. 

Safe  loads  in  pounds  per  square  foot. 

1-6 

1376 

1608 

1840 

2000 

2000 

2000 

2000 

2-0 

764 

893 

1023 

1152 

1717 

2000 

2000 

2-6 

480 

563 

645 

727 

1087 

1307 

2000 

3-0 

326 

383 

440 

496 

745 

897 

1412 

3-3 

275 

323 

371 

419 

630 

759 

1197 

3-6 

233 

275 

316 

357 

538 

649 

1025 

3-9 

200 

236 

272 

307 

465 

561 

887 

4-0 

173 

204 

236 

267 

404 

488 

774 

4-3 

151 

178 

206 

233 

354 

429 

681 

4-6 

132 

156 

181 

204 

312 

378 

602 

4-9 

116 

137 

159 

181 

277 

336 

536 

5-0 

102 

L22 

141 

160 

247 

299 

479 

5-3 

91 

108 

126 

143 

221 

268 

430 

5-6  , 

96 

112 

127 

198 

241 

388 

5-9 

86 

100 

114 

179 

217 

351 

6-0 

77- 

90 

102 

161 

197 

319 

6-3 

81 

92 

146 

178 

290 

6-6 

73 

83 

132 

162 

265 

6-9 

66 

75 

120 

148 

242 

7-0 

68 

110 

135 

222 

7-6 

~55 

91 

113 

187 

8-0 

76 

94 

159 

8-6 

80 

136 

9-0 

67 

116 

10-0 

47 

"85 

11-0 

62 

12-0 

45 

Note.  —  If  webs  thicker  than  f  inch  are  used,  the  loads  given  in  above  table 
may  be  increased  in  direct  proportion  to  increase  of  sectional  area. 


556 


FIRE    PREVENTION   AND    FIRE    PROTECTION 


SAFE  LOADS— SIDE-CONSTRUCTION  FLAT  ARCHES. 

Material,   semi-porous.     Factor  of  safety  7. 

Heavy  Sections. 


6,  8,9  and  10-inch  arch.  12  and  15-inch  arch. 

Note.  —  In  following  table  the  weight  of  arch  blocks  has  been  deducted  from 
the  safe  load.  The  weight  of  cinder-fill,  flooring  and  plastering  must  be  de- 
ducted to  obtain  net  live  load. 

The  widest  span  permissible  for  any  arch  is  indicated  by  cross  rule  in  the 
column.  Beyond  this  span  it  should  be  used  only  as  a  ceiling  arch. 


Arches. 

6  in. 

7  in. 

8  in. 

9  in. 

10  in. 

12  in. 

15  in. 

Weight  of 

arches,  pounds 

26 

28 

30.6 

31.2 

33.4 

38.3 

40.6 

per  square  foot. 

Cross-sectional 

area  of  blocks, 

30 

30 

30 

31.5 

33 

37.5 

38 

square  inches. 

Spans,  feet  and 
inches. 

Safe  loads  in  pounds  per  square  foot. 

1-6 

1840 

2148 

2458 

2500 

2500 

2500 

2500 

2-0 

1022 

1196 

1369 

1623 

1892 

2500 

2500 

2-6 

645 

754 

865 

1027 

1199 

1642, 

2087 

3-0 

439 

515 

592 

704 

822 

1128 

1437 

3-3 

370 

434 

500 

595 

696 

956 

1219 

3-6 

314 

371 

427 

509 

595 

819 

1045 

3-9 

270 

320 

368 

439 

514 

708 

905 

4-0 

234 

276 

319 

382 

448 

618 

791 

4-3 

204 

243 

280 

335 

393 

543 

696 

4-6 

178 

213 

246 

296 

347 

480 

616 

4-9 

158 

188 

218 

262 

308 

427 

549 

5-0 

140 

167 

193 

233 

275 

382 

491 

5-3 

124 

140 

173 

209 

246 

343 

442 

5-6 

133 

155 

.188 

221 

309 

399 

5-9 

'  118 

139 

169 

200 

279 

362 

6-0 

107 

125 

153 

181 

253 

329 

6-3 

113 

138 

164 

231 

300 

6-6 

102 

125 

149 

210 

274 

6-9 

92 

114 

136 

192 

251 

7-0 

104 

124 

176 

231 

7-6 

l6 

104 

148 

196 

8-0 

1 

126 

167 

8-6 

87 

107 

144 

9-0 

91 

124 

9-6 

78 

107 

Example:  Required,  the  safe  load  of  12-inch  arch,  span  8  feet,  using  arch 
block  having  cross-sectional  area  of  31.5  square  inches.  Area  of  arch  block 
used  38.5)31.5  =  .82,  which  X  126  pounds  =  103  pounds  safe  load  required< 

Example:  Required,  the  safe  load  for  8-inch  arch,  span  5  feet  6  inches,  with 
factor  of  safety  of  5  instead  of  7.  155  pounds  -f-  30.6  pounds  (dead  load)  = 
185.6  X  7  =  1299.2  -f-  5  =  259.8  -  30.6  =  229.2  pounds  safe  load  required. 


TERRA-COTTA    FLOORS,  GIRDER   PROTECTIONS,  ETC.       557 

End-construction  Arches.  —  In  this  type  of  arch  the  cells 
and  sides  of  the  blocks  run  at  right  angles  to  the  beams,  from 
beam  web  to  beam  web.  Hence  the  arch  pressure  is  always 
against  the  ends  of  the  blocks,  and  as  hollow  tiles  are  always 
stronger  under  end  compression  than  under  side  compression  (for 
tests  see  page  588),  an  end-construction  arch  will  develop  about 
50  per  cent,  more  strength,  for  the  same  weight,  if  properly  set, 
.than  a  side-construction  arcn.  End-construction  lengtheners, 
at  least,  have  therefore  largely  superseded  side-construction, 
and  it  is  probable  that  fully  75  per  cent,  of  all  hollow-tile  arch 
blocks  now  used  are  of  the  end-construction  type.  The  straight 
end-construction  arch  is  more  largely  used  in  the  western  than 
in  the  eastern  states,  especially  for  deep  arches,  and  United  States 
Government  specifications  have  usually  called  for  this  type  where 
hollow-tile  arches  are  used. 

From  the  standpoint  of  corrosion,  end-construction  skews  are 
decidedly  inferior  to  side-construction  skews,  as  the  end  bearing 
only  of  the  former  prevents  that  continuous  mortar  bed  against 
the  webs  of  the  beams  which  is  secured  when  the  side-construc- 
tion type  is  used.  A  true  and  solid  bearing  against  the  beams 
is  also  more  difficult  to  secure  in  the  end-construction  skew. 

The  lengtheners  are  usually  made  12  inches  wide  and  12  inches 
long,  the  interior  webs  varying  with  the  depth  and  required 
strength.  Six-inch  blocks  are  commonly  made  without  interior 
horizontal  webs,  8,  9,  10  and  12-inch  blocks  with  one  horizontal 
web,  and  15  and  16-inch  blocks  with  two  webs. 

For  semi-porous  blocks  the  usual  thickness  of  the  outer  shells 
is  f  inch,  and  for  the  interior  webs  about  1  inch.  The  cells 
should  preferably  be  not  over  3|  inches  in  either  direction. 

Both  end-  and  side-construction  keys  are  used  in  end-con- 
struction, arches,  the  former  being  generally  used  when  the  span 
requires  a  key  over  6  inches  wide,  and  the  latter  for  6  inches  or 
less. 

The  objections  to  end-construction  arches  are,  —  first,  that 
the  blocks  cannot  be  made  to  break  joint,  —  second,  that  a  true 
end-bearing  and  mortar  joint  is  more  difficult  to  obtain  than 
with  side-construction  blocks,  —  and  third,  that  more  mortar 
must  be  used  on  account  of  the  waste  in  the  cells.  Objections 
one  and  two  can  be  disregarded  in  view  of  the  excess  strength 
obtained  through  using  the  end-construction  method,  while 
objection  three  is  of  small  consequence, 


558        FIRE   PREVENTION   AND   FIRE   PROTECTION 

HI 


FIG.   192.  —  End-construction  Hollow  Tile  Arch. 

Fig.  192  illustrates  a  straight  end-construction  arch  as  used 
for  short  spans  and  shallow  depths.     Fig.  193  shows  a  12-inch 


FIG.  193.  —  End-construction  Arch  with  Side-construction  Key. 

or  13-inch  end-construction  arch  with  side-construction  key, 
and  Fig.  194  a  14-inch,  15-inch  or  16-inch  arch  of  the  same 
construction. 


FIG.  194.  —  Deep  End-construction  Arch  with  Side-construction  Key. 

The  weights  of  standard  end-construction  arches  per  square 
foot  and  the  permissible  spans  are  as  follows: 


Spans  allowable  between  I-beams. 

inches. 

square  foot. 

Arch  set  flat, 

Set  with  slight  cam- 

feet and  inches. 

ber, 
feet  and  inches. 

6 

20  to  26 

4-6 

5-0 

7 

22  to  29 

5-0 

5-9 

8 

24  to  32 

5-6 

6-6 

9 

26  to  36 

6-0 

7-0 

10 

28  to  38 

6-6 

7-6 

12 

30  to  44 

7-6 

9-0 

15 

37  to  50 

9-0 

10-0 

For  table  of  safe  loads,  see  page  567. 


TERRA-COTTA  FLOORS,  GIRDER  PROTECTIONS,  ETC.   559 

X-tile  End-construction  Arches.  —  This  designation  is 
given  to  blocks  having  recessed  sides,  thus  giving  somewhat  the 
appearance  of  the  letter  X,  as  shown  in  Fig.  195.  The  construc- 


FIG.   195.  —  X-tile  End-construction  Arch. 

tion  was  devised  with  the  idea  of  permitting  tie-rods  to  span  the 
bays  without  the  cutting  or  interference  of  the  arch  blocks,  and 
also  of  reducing  the  arch  weight  by  the  use  of  large  voids.  As 
a  matter  of  fact  the  spacing  of  tie-rods  is  not  often  sufficiently 
regular  to  be  counted  on.  This  type  has  had  but  limited  use, 
and  is  now  seldom  employed.  A  deeper  and  heavier  arch  of 
the  same  type  is  shown  in  Fig.  196. 


FIG.  196.    X-Tile  End-construction  Arch,  Heavy  Pattern. 

"New  York"  Reinforced  End-construction  Arch.  —  This 
construction  was  designed  and  patented  by  Mr.  P.  H.  Bevier  of 
the  National  Fire  Proofing  Company  for  use  under  the  New  York 
building  law  requirements.  It  was  designed  primarily  to  secure 
a  light  and  cheap  but  strong  floor  system  which  might  successfully 
compete  with  medium-span  concrete  arches,  and  which,  through 
metal  reinforcement,  might  reduce  the  building  code  require- 
ments as  to  depth  of  arch. 

The  New  York  building  law  requires  hollow-tile  arches  (unless 
reinforced,  in  which  case  they  are  subject  to  actual  tests  to  the 
satisfaction  of  the  building  department),  to  be  of  a  " depth  not 
less  than  1J  inches  for  each  foot  of  span,  not  including  any  por- 
tion of  the  depth  of  the  tile  projecting  below  the  under  side  of  the 
beam."  Allowing  1  inch  for  the  projection  of  arches  below  the 
beams,  this  would  require  an  arch  11  f  inches  deep  for  a  6-foot 


560         FIRE   PREVENTION   AND   FIRE   PROTECTION 

span,  and  a  14-inch  arch  for  a  7^-foot  span.  The  New  York 
Bureau  of  Buildings  has  tested  and  accepted  the  6-inch  "New 
York"  arch  for  6-foot  spans,  and  the  8-inch  arch  for  7J-foot 
spans,  under  a  live  load  of  150  pounds  per  square  foot.  The 
saving  in  weight  and  expense  in  both  the  floor  system  and  in  the 
supporting  steel  work  is  apparent. 

The  "  New  York "  arch  is  particularly  adapted  to  wide  spans 
with  shallow  beams,  and  it  has  been  extensively  used  in  New 
York  City,  especially  for  hotels,  apartment  houses,  residences, 
etc.,  where  a  light  floor  is  required  at  low  cost. 

The  construction  is  as  shown  in  Fig.  197.  End-construction 
blocks  are  used,  the  skews  usually  resting  on  and  projecting 


-T.C.  Soffit  Til 

^"Mortar  Jointx^ 

^a^ 

IW 

n 

a 

,0 

m 

0 

0 

00 

(Wire  Truss  1 

Metal  Lath 


1  inch  below  the  beams.  Between  the  successive  arch  courses, 
i-inch  mortar  joints  are  used,  in  which  a  wire  truss  reinforcement, 
as  illustrated  in  Fig..  198,  is  placed.  The  open  construction  of 


FIG.   198.  — Wire  Truss  Reinforcement,  "New  York"  Arch. 

the  wire  truss  permits  the  mortar  to  flow  freely  around  it,  and 
as  Portland  cement  mortar  is  used,  the  reinforcement  is  amply 
protected  against  both  fire  and  corrosion.  It  is  shipped  to  the 


TERRA-COTTA  FLOORS,  GIRDER  PROTECTIONS,  ETC.   561 

building  on  reels,  and  is  cut  to  proper  lengths  on  the  job  as  re- 
quired. Light  cinder  concrete  or  dry  cinders  are  used  to  level 
up  to  the  tops  of  beams. 

Where  deep  beams  are  employed,  the  blocks  may  be  set  level 
with  the  tops  of  the  beams  by  means  of  beam  protection  blocks 


FIG.  199.  —  "New  York"  Arch  with  Suspended  Ceiling. 


under  the  skews,  as  shown  in  Fig.  199.  The  soffit  may  then  be 
plastered  so  as  to  give  a  paneled  ceiling,  or  a  flat  suspended 
ceiling  may  be  used. 

Load  tests  have  shown  an  ultimate  strength  of  1600  pounds 
per  square  foot  for  a  6-inch  arch  on  a  6-foot  span. 

The  weights  per  square  foot,  including  supporting  beams,  are 
as  follows  for  various  constructions: 


Blocks  1  inch  below  I's.     Dry 

Raised  construction.     Top  of 

cinder-fill  to  top  of  I's.     2-inch 

arch  level  with  top  of  I's.    2- 

Size  of  sup- 
porting , 
beams. 

wood  sleepers  with  cinder  con- 
crete between.    Plaster  ceiling. 
1-inch  maple  floor. 

inch  cinder  concrete  between 
2-inch  sleepers.   Plaster  ceiling. 
1-inch  maple  floor. 

6-inch  arch. 

8-inch  arch. 

Paneled  ceiling 

Suspended  ceil- 
ing. 

Inches. 

Pounds. 

Pounds. 

Pounds. 

Pounds. 

15 

80 

52 

56 

12 

73 

67 

50 

54 

10 

64 

58 

47 

9 

60 

54 

8 

55 

49 

7 

51 

44 

6 

47 

562         FIRE    PREVENTION    AND    FIRE    PROTECTION 

The  "Johnson  Long-span"  Floor  is  a  reinforced  end-con- 
struction system,  patented  by  Mr.  E.  V.  Johnson  of  the  National 
Fire  Proofing  Company.  This  system  has  been  extensively 
used,  the  manufacturers  claiming  an  installation  in  excess  of 
five  millions  of  square  feet  in  a  great  variety  of  structures. 

A  perspective  of  the  construction  is  shown  in  Fig.  200.  The 
floor  is  built  on  a  flat  wood  centering,  over  which  is  spread  a 


Reinforcing  Rods 
Fia.  200.  —  "Johnson  Long-span"  End-construction  Arch. 

1-inch  layer  of  1  :  4  Portland  cement  mortar  in  which  is  embedded 
a  metal  reinforcement,  consisting  of  large  steel  wires,  placed 
usually  4  ins.  apart,  transversely  interwoven  with  still  larger 
wires,  or  reinforcing  rods.  These  latter  rods,  varying  from  J  to 
J  inch  in  size  and  from  2  inches  to  8  inches  centers  according  to 
the  span  and  load,  run  straight  from  bearing  to  bearing.  End- 
construction  tile  varying  in  depth  from  3  inches  to  12  inches  are 
then  laid  so  as  to  break  joint,  and  so  as  to  form  continuous  arches 
between  the  supports.  One-inch  mortar  joints  are  used  between 
the  courses  or  individual  arches,  and  the  whole  is  covered  with 
1  or  2  inches  of  1  :  4  cement  mortar. 

This  system  has  been  successfully  used  for  spans  as  great  as 
25  feet,  but  16-  or  18-foot  spans  are  the  most  advantageous.  The 
principle  of  construction  is  essentially  the  same  as  in  flat  slab 


TERRA-COTTA   FLOORS,  GIRDER  PROTECTIONS,  ETC.      563 

Finished  Floor 


FIG.  201.  —  "Johnson"  Arch,  as  used  in  Underwriters'  Laboratories,  Inc., 
Chicago. 

concrete  floors  where  an  expanded  metal  or  similar  tension  mem- 
ber is  placed  at  the  bottom  of  slab,  except  that  hollow  tile  are 
substituted  for  the  upper  portion  of  the  slab,  thus  materially 
reducing  the  weight. 


FIG.  202.  —  "Johnson"  Arch  carried  on  Lower  Flanges  of  Beams. 

The  strength  of  the  Johnson  system  depends  mainly  upon 
the  metal  reinforcement  and  upon  the  adhesion  of  the  lower 
layer  of  cement  mortar  to  the  steel  and  tile,  but  numerous  tests 
show  that  the  construction  is  capable  of  carrying  very  great 
loads. 

A  section  of  this  floor,  16  feet  square,  supported  on  walls 
around  the  four  edges,  was  loaded  over  its  entire  area  with  a  total 
uniformly  distributed  load  of  187,680  pounds  or  733  pounds  to 
each  square  foot.  The  deflection  of  the  floor  was  as  follows: 
Under  a  load  of  350  pounds  per  square  foot,  J  inch  scant;  733 
pounds  per  square  foot,  |  inch  full.* 

*  Rudolph  P.  Miller,  in  Kidder's  Architects'  and  Builders'  Pocketbook. 


564         FIRE   PREVENTION   AND   FIRE   PROTECTION 


The  following  table,    used   by  the   National   Fire   Proofing 
Company,  gives  the  safe  loads  for  this  construction: 


»  08       "3  «  J 
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SI 

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111  si 

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cit^-coi—  (eotocxscooooooo^cDoocvioo 


M  CS  <M  <M  C^l  C^l 


TERRA-COTTA    FLOORS,  GIRDER   PROTECTIONS,  ETC.       565 

The  floor  construction  in  the  model  fire-resisting  building  of 
the  Underwriters'  Laboratories,  Incorporated,  Chicago,  is  of  the 
Johnson  long-span  system,  as  above  described,  but  with  a  special 
ceiling  construction.  This  consists  of  2-inch  flat,  porous  tile, 
laid  first  on  the  flat  centering  in  herringbone  fashion.  The  edges 
of  these  tile  were  grooved,  so  as  to  receive  metallic  clips  which 
were  secured  to  the  wire  reinforcement  previously  described. 
Fig.  201  illustrates  these  ceiling  tile  in  plan,  and  a  cross-section 
of  the  entire  construction.  The  exposed  joints  in  the  ceiling 
tile  were  raked  out  after  the  centering  was  struck,  and  were  then 
pointed.  The  floors  were  finished  with  a  smooth  coat  of  cement. 

By  lowering  the  regular  Johnson  construction  so  that  the 
metal  reinforcement  and  the  skews  will  bear  on  the  lower  flanges 
of  the  beams,  a  flat  ceiling  may  be  obtained  as  shown  in  Fig.  202. 
This  arrangement,  however,  is  not  as  economical  as  the  former, 
as  the  concrete-fill  is  usually  much  more  than  is  required  for 
strength. 

Combination  End-  and  Side-construction  Arches.  —  Hol- 
low-tile arches  made  of  side-construction  skews  and  keys  in  com- 
bination with  end-construction  lengtheners  may  properly  be 
considered  the  standard  terra-cotta  arch  practice  of  the  present 
day.  They  are  almost  invariably  used  in  the  eastern  states 
unless  some  special  type,  like  the  " Excelsior"  or  "New  York" 
reinforced  arch,  is  specified. 

This  combination  has  largely  been  brought  about  by  the 
manufacturers  of  hollow-tile  floors  for  the  following  reasons :  — 
first,  on  account  of  the  greater  facility  with  which  the  side-con- 
struction skews  may  be  set  in  place  against  the  beams,  —  second, 
on  account  of  the  better  protection  afforded  the  beam  webs 
against  corrosion,  through  the  continuous  mortar  joint,  —  and 
third,  on  account  of  saving  the  mortar  lost  in  the  voids  of  end- 
construction  skews.  These  points  have  been  considered  in 
detail  in  previous  paragraphs,  but  a  fourth  practical  considera- 
tion in  connection  with  combination  arches,  not  previously 
touched  upon,  is  the  better  protection  afforded  the  beam  webs 
and  lower  flanges,  against  fire,  through  the  use  of  side-construc- 
tion skews.  Thus  if  the  lower  outside  shell,  or  the  soffit,  of  an 
end-construction  skew  is  damaged  or  split  off  under  fire,  the 
beam  flange  and  lower  portion  of  web  are  exposed,  whereas  in 
the  side-construction  skew,  a  similar  occurrence  would  still  leave 
the  vertical  shell  against  the  beam.  Also,  in  the  end-construe- 


566        FIKE   PREVENTION   AND   FIRE   PROTECTION 

tion  skew  the  soffit  shell  is  usually  of  considerably  more  area  and 
much  wider  between  the  supporting  vertical  shells  than  in  the 
side-construction  skew,  and  is,  therefore,  much  more  liable  to 
split  off  under  fire. 

Fig.  203  shows  the  standard  combination  arch  made  by  the 
Illinois  Terra-cotta  Lumber  Company,  Chicago,  the  depths  and 


FIG.  203.  —  Combination  Arch. 

weights  of  which  are  as  follows:  7-inch  arch,  28  pounds;  8-inch 
arch,  30  pounds;  9-inch  arch,  32  pounds;  10-inch  arch,  34 
pounds;  11-inch  arch,  35  pounds;  12-inch  arch,  38  pounds;  13- 
inch  arch  40  pounds;  14-inch  arch,  43  pounds;  15-inch  arch, 
46  pounds;  16-inch  arch,  50  pounds. 


(  (outer  Shell,  X'thick 
Sinner  Bibst%yy    " 

FIG.  "204.  —  Combination  Arch,  U.  S.  Court  House  and  Post  Office, 
Los  Angeles,  Cal. 

Fig.  204  shows  the  alternate  combination  hollow-tile  floor  con- 
struction as  specified  for  the  United  States  Court  House  and 
Post  Office  at  Los  Angeles,  Cal. 

The  following  table,  used  by  the  National  Fire  Proofing  Com- 
pany, gives  the  safe  loads,  etc.,  for  various  depths  of  arches  and 
spans  for  either  end-  or  combination-construction  arches. 

SAFE  LOADS  —  END-  AND  COMBINATION-CONSTRUC- 
TION FLAT   ARCHES. 

Material,  semi-porous.    Factor  of  safety,  7. 

The  following  table  is  applicable  to  all  shapes  of  blocks.  The  areas  given 
are  obtained  by  passing  a  plane  through  the  blocks  at  right  angles  to  all  the 
webs  (instead  of  parallel  to  the  webs  as  in  previous  tables).  Generally  speak- 


TERRA-COTTA    FLOORS,  GIRDER   PROTECTIONS,  ETC.       567 


ing,  end-construction  blocks  of  various  shapes  but  of  the  same  depth  and  cross- 
sectional  area  have  equal  strength. 

The  weight  of  the  arch  has  not  been  deducted  from  safe  loads  in  table  below, 
therefore  this  and  other  dead  load  must  be  deducted  to  obtain  the  net  safe  live 
load  for  any  arch  and  span. 


Arches. 

6  in. 

7  in. 

Sin. 

9  in. 

10  in. 

12  in. 

15  in. 

Areas. 

31  sq.  in. 

34  sq. 
in. 

37  sq. 
in. 

40  sq. 
in. 

43  sq.  in. 

49  sq.  in. 

58  sq.  in. 

Spans, 
ft.  and  in. 

Lbs. 

Lbs. 

Lbs. 

Lbs. 

Lbs. 

Lbs. 

Lbs. 

1-6 

1928 

2468 

3069 

3733 

4459 

6097 

9022 

2-0 

1085 

1388 

1726 

2100 

2508 

3430 

5075 

2-6 

694 

888 

1104 

1344 

1605 

2195 

3248 

3-0 

482 

617 

767 

933 

1114 

1524 

2255 

3-3 

410 

525 

654 

795 

950 

1299 

1922 

3-6 

354 

453 

563 

685 

819 

1120 

1657 

3-9 

308 

394 

491 

597 

713 

975 

1443 

4-0 

271 

347 

431 

525 

627 

857 

1268 

4-3 

240 

307 

382 

465 

555 

759 

1124 

4-6 

214 

274 

341 

414 

495 

677 

1002 

4-9 

192 

246 

306 

372 

444 

608 

900 

5-0 

173 

222 

276 

336 

401 

548 

812 

5-3 

157 

201 

250 

304 

364 

497 

736 

5-6 

143 

183 

228 

277 

331 

453 

671 

5-9 

131 

168 

208 

254 

303 

415 

614 

6-0 

120 

154 

191 

233 

278 

381 

563 

6-3 

111 

142 

176 

215 

256 

351 

519 

6-6 

131 

163 

198 

237 

324 

480 

6-9 

121 

151 

184 

220 

301 

445 

7-0 

113 

140 

171 

204 

280 

414 

7-6 

122 

149 

178 

243 

360 

8-0 

107 

131 

156 

214 

317 

8-6 

116 

138 

190 

281 

9-0 

103 

123 

169 

250 

9-6 

111 

152 

225 

10-0 

100 

137 

203 

10-6 

124 

184 

11-0 

113 

167 

11-6 

103 

153 

12-0 

95 

141 

Example:  What  load  will  an  8-inch  arch  carry  with  a  factor  of  safety  of  5 
for  a  span  of  5  feet  6  inches,  the  blocks  having  a  sectional  area  parallel  to  the 
beams  of  44.25  square  inches  (the  webs  being  f-inch  thick  and  three  horizontal 
and  four  vertical)? 

The  area  of  8-inch  arch  used  in  table  is  37  square  inches.  44.25  -j-  37  =  1.19. 
Safe  load  given  in  table,  228  X  1.19  =  271  pounds.  Weight  of  arch  =  44.25  X 
12  =  531  cubic  inches  X  .06  =  say  32  pounds;  271  -  32  =  239  safe  load  per 
square  foot  for  factor  of  safety  of  7;  271  X  7  =  1897  -i-  5  =  379  -  32  =  247 
safe  load  per  square  foot  for  factor  of  safety  of  5. 

"Excelsior"  End-  and  Side-construction  Arch. —  This 
combination  arch,  made  by  Henry  Mauler  &  Son,  New  York, 


568 


FIRE    PREVENTION    AND    FIRE    PROTECTION 


as  shown  in  Fig.  205,  is  practically  the  same  as  the  X-tile  end- 
construction  type  previously  described,   except  that  side-con- 


FIG.   205.  —  "Excelsior"  Combination  Arch. 

struction   skews   are   used.     The   following   spans,   depths   and 
weights  per  square  foot  are  given  by  the  manufacturers : 

8-inch  arch,  5-foot  to  6- foot  span,  27  pounds  per  square  foot. 

9-inch  arch,  6  foot  to  7-foot  span,  29  pounds  per  square  foot. 
10-inch  arch,  7-foot  to  8-foot  span,  33  pounds  per  square  foot. 
12-inch  arch,  8-foot  to  9-foot  span,  38  pounds  per  square  foot. 

Depth  of  Standard  Flat  Arches.  —  A  safe  rule  for  deter- 
mining the  proper  depth  of  flat  standard  hollow-tile  arches  is 
that  the  depth  in  inches  should  equal  the  span  in  feet  X  1 1  +  the 
2-inch  projection  of  the  arch  below  the  beams. 

The  best  practiced  to  make  the  arch  blocks  1  inch  deeper  than 
the  supporting  beams,  in  which  case  the  top  of  the  arch  is  set 
1  inch  below  the  tops  of  beams,  thus  allowing  the  blocks  to  pro- 
ject 2  inches  below  the  beams,  as  shown  in  Fig.  206.  Concrete 


FIG.  206.  —  End-construction  Arch,  Wanamaker  Store,  N.  Y. 

filling  should  then  be  leveled  up  to  or  above  the  tops  of  beams, 
as  explained  in  later  paragraph  " Floor  Finish."     Arches  2  inches 


TERRA-COTTA   FLOORS,  GIRDER   PROTECTIONS,  ETC.       569 


deeper  than  the  deepest  beams,  as  used  in  the  Milwaukee  Electric 
Railway  and  Light  Company's  Building  are  shown  in  Fig.  207. 


FIG.  207.  —  Combination  Arch,  Milwaukee  Electric  Ry.  &  Light  Co.'s  Building. 

Deep  arches  with  a  shallow  concrete  fill  are  not  only  much 
stronger  but  are  also  lighter  in  weight  than  a  shallower  arch  with 
more  fill.  Thus  for  a  span  of  6  feet,  between  12-inch  beams, 
10-inch  and  12-inch  arches  of  a  total  depth  of  15-J-  inches,  may 
be  contrasted,  as  to  weight,  as  follows: 


10-inch  arch. 

12-inch  arch. 

f-inch  granolithic  floor  
Cinder-concrete  fill     

Lbs. 
10 
4  ins.,  22 

Lbs. 
10 
2  ins.,  11 

Hollow-tile  arch 

36 

40 

Plastering                          

5 

5 

Beams     

5 

5 

Total  dead  load  

78 

71 

Tile  filler  blocks,  as  shown  in  Fig.  205,  are  sometimes  employed 
instead  of  concrete  fill  over  the  arches,  but  they  add  nothing 
to  the  strength  of  an  arch  while  they  are  more  expensive  than 
if  the  arch  blocks  were  increased  by  an  equivalent  depth. 

Raised  Skewbacks.  —  The  purpose  of  this  form  is  to  reduce 
the  dead  load  or  weight  of  the  arch  itself,  or  to  reduce  the  amount 


FIG.  208.  —  Side-construction  Arch  with  Raised  Skewbacks  . 

of  concrete  filling  necessary  to  level  up  to,  or  cover,  the  beams. 
Figs.  208,  209  and  210  show  forms  of  raised  skewbacks  for  side-, 


to 


FIRE   PREVENTION    AND    FIRE    PROTECTION 


end-  and  combination-construction  arches  respectively.     These 
are  often  used  in  floor  or  roof  construction,  where,  in  consequence 


. 


FIG.  209.  —  End-construction  Arch  with  Raised  Skewbacks. 

of  deep  beams  made  necessary  by  long  spans,  the  floor  arches 
can  be  made  of  a  shallower  depth  than  the  beams,  thereby  ma- 


FIQ.  210.  —  Combination  Arch  with  Raised  Skewbacks. 

terially  reducing  the  load  per  square  foot  and  the  consequent 
cost. 

Segmental  Arches  are  the  cheapest  and  strongest  hollow-tile 
arches  made,  but,  on  account  of  the  arched  ceilings  resulting 
from  the  employment  of  such  forms,  their  use  has  generally  been 
limited  to  warehouses,  factories,  lofts  or  breweries,  etc.,  where 
considerable  loads  have  to  be  carried  without  regard  to  the 


Double  Rowlock  Arch  Single  Rowlock  Arcl 

FIG.   211.  —  "Haverstraw"  Hollow  Brick  Segmental  Arches. 

appearance  of  the  ceiling.  In  office  and  store  buildings  a  ceiling 
of  unbroken  plane  is  usually  desired  on  account  of  the  appear- 
ance, as  well  as  for  the  sake  of  the  light,  which  is  better  reflected 
from  a  uniform  surface  than  from  a  broken  or  segmental  ceiling. 
A  level  ceiling  is  also  more  effective  from  a  fire-resisting  stand- 
point, as  has  previously  been  shown  (see  page  342).  For  par- 
ticularly heavy  loads,  as  in  driveways  where  loaded  teams  must 
be  provided  for,  segmental  arches  should  preferably  be  made  of 


TERRA-COTTA    FLOORS,  GIRDER   PROTECTIONS,  ETC.       571 

double-rowlock  "Haverstraw"  hollow  brick,  as  shown  in  Fig.  211. 
This  construction  will  weigh  31  pounds  per  square  foot  for  the 
4-inch  or  single-rowlock  arch,  and  65  pounds  for  the  8-mch  or 
double  rowlock. 

For  ordinary  loads,  segmental  arches  are  generally  made  of 
6-inch  or  8-inch  hollow-tile  blocks,  of  the  side-construction 
method,  as  shown  in  Fig.  212.  This  type  is  both  lighter  and  more 


Tie  Rod 
FIG.  212.  —  Side-construction  Segmental  Arch. 

economical  than  the  hollow-brick  arch,  and  for  ordinary  condi- 
tions the  6-inch  arch  will  be  found  sufficient.  The  weight  per 
square  foot  of  the  usual  6-inch  segmental  arch  is  27  pounds,  and 
of  the  8-inch  arch,  33  pounds.  i 

The  end-construction  method  is  sometimes  employed  for  seg- 
mental arches,  but  it  is  unsatisfactory  unless  the  arches  are  of 
uniform  span  and  rise  throughout.  In  the  side-construction 
arch,  the  rise  may  be  varied  by  increasing  or  decreasing  the 
thickness  of  the  mortar  in  the  upper  portions  of  the  joints  be- 
tween the  blocks,  but  this  cannot  be  done  with  end-construction 
blocks. 

Segmental  arches  have  been  successfully  used  in  spans  as  great 
as  24  feet,  but  16  feet  should  ordinarily  be  the  limit.  The  rise 
should  be  not  less  than  1  inch  per  foot  of  span,  and  1J  inches  is 
preferable.  For  long  spans  or  heavy  loads,  substantial  skews 
are  necessary  to  resist  the  arch  thrust.  In  some  instances  the 
second  blocks  from  the  skews  are  made  to  line  with  top  of  arch, 
as  shown  in  dotted  lines  in  Fig.  212,  the  idea  being  to  bring  the 
concrete  haunches  back  of  these  blocks  in  compression,  so  as 
partly  to  relieve  the  thrust  on  the  skewbacks. 

Raised  skewbacks  are  sometimes  employed  with  elliptical 
arches.  The  arch  is  thereby  raised  at  the  skew,  and  correspond- 
ingly flattened,  thus  decreasing  the  dead  load  of  concrete 
haunches,  but  decreasing  the  strength  of  the  arch  as  well. 

A  short-span  6-inch  segmental  arch  with  full  depth  skews, 
as  used  in  the  Western  Electric  Company's  Building,  Chicago, 


572         FIRE    PREVENTION    AND    FIRE    PROTECTION 

is  shown  in  Fig.  213.  Skews  of  this  pattern,  with  rounded  lips 
to  hold  the  soffit  tile,  are  easier  and  cheaper  to  plaster  than  those 
forming  an  arris. 


^Wood  Floor  I 

sg$^T  ""•'.-:-~'-*~~-".-  .•'-_•" 

NYu'iU  Sct-mls; .; ;  -     C 


FIG.  213.  —  Short-span  Segmental  Arch,  Full  Depth  Skews. 


Segmental  arches,  whether  made  of  hollow  brick  or  tile,  should 
always  be  laid  so  as  to  break  joints,  brick  fashion.  The  haunches 
should  be  filled  in  with  cinder  concrete,  which  should  be  leveled 
up  to  a  point  not  less  than  1  inch  above  the  crown.  This  to 
prevent  a  direct  concussion  upon  the  blocks  themselves.  On 
long-span  arches  the  concrete  should  be  of  good  quality,  as  the 
strength  of  the  arch  at  the  haunches  or  end-quarter  portions  of 
the  span  largely  depends  upon  the  concrete,  especially  under 
uneven  loading. 

Segmental  Arches  with  Suspended  Ceilings. —  The  curved 
soffit  resulting  from  the  use  of  segmental  arches  may  be  concealed 
by  the  use  of  a  suspended  ceiling  as  shown  in  Fig.  214.  This 


FIG.  214.  —  Segmental  Arch  with  Suspended  Ceiling. 

form  of  construction  has  been  largely  employed  in  the  newer 
public  school  buildings  in  New  York  City.  It  is  both  strong  and 
economical  under  long  spans,  where  heavy  loads  are  specified; 
but  where  the  spans  are  moderate,  so  that  an  ordinary  flat  arch 
may  be  used,  the  latter  is  to  be  preferred. 

The  efficiency  of  suspended  ceilings  has  been  discussed  in 
Chapter  XI,  page  343. 


TERRA-COTTA   FLOORS,  GIRDER  PROTECTIONS,  ETC.       573 

In  the  following  table,  as  used  by  the  National  Fire  Proofing 
Company,  the  safe  loads  for  segmental  arches  are  given  with  a 
factor  of  safety  of  7.  Blocks  with  the  following  sectional  areas 
(per  foot  of  arch  parallel  with  beams),  are  assumed:  4-inch  arch, 
28  square  inches;  6-inch,  36  square  inches;  8-inch,  43  square 
inches;  10-inch,  47  square  inches.  The  weight  of  the  arch 
blocks  has  been  deducted  in  the  table,  so  that  only  the  dead  load 
of  concrete  fill,  pastering,  etc.,  must  be  deducted  to  obtain  net 
live  load. 

Explanation  of  Table. 

The  safe  load  in  pounds  per  square  foot  uniformly  distributed 
is  for  a  factor  of  safety  of  7  for  semi-porous  material  for  blocks 
of  sectional  areas  given  at  head  of  table.  To  obtain  safe  load 
of  blocks  of  any  other  thickness,  compute  the  cross-sectional 
area  in  compression  per  lineal  foot  of  arch.  Divide  this  area  by 
the  area  of  the  block  used  in  table.  This  will  give  the  safe  load 
coefficient  for  this  special  block.  Multiply  any  weight  given 
in  table  for  the  same  depth  of  arch  by  this  coefficient,  and  it  will 
give  the  safe  load  for  the  special  arch.  The  weights  of  the  arch 
blocks  have  been  deducted  to  give  the  table  weights.  Deduct 
other  dead  loads  of  concrete  fill,  plastering,  etc.,  to  obtain  safe 
net  load. 

Example.  —  What  is  the  strength  of  a  6-inch  segmental  arch, 
span  7  feet,  rise  1J  inches  per  foot  of  span,  side-construction 
blocks  having  three  horizontal  webs  f  inch  thick?  Cross-sectional 
area  equals  f  inch  X  12  inches  X  3  inches,  equals  22.5  square 
inches,  which,  divided  by  36,  equals  .62,  the  coefficient.  There- 
fore, 834  pounds,  given  in  table,  X  .62  equals  519  pounds  safe 
load  required.  If  the  arch  blocks  are  used  end  construction,  all 
the  webs  would  be,  in  compression,  and  the  sectional  area  of  a 
block  with  four  vertical  and  three  horizontal  ribs  X  I  inch  thick 
is  32.8  square  inches,  which,  divided  by  36,  equals  .91,  the  coeffi- 
cient. 834  X  .91  equals  759  pounds. 

The  weights  deducted  for  dead  load  of  arches  in  table  are  as 
follows:  4-inch  arch,  17.3  pounds;  6-inch,  21.6  pounds;  8-inch, 
25.8  pounds;  10-inch,  28.5  pounds.  To  obtain  weight  of  any 
block,  multiply  its  cross-sectional  area  in  square  inches  by  12 
inches,  equals  cubic  inches  of  material  per  lineal  foot,  which, 
multiplied  by  .06  pounds,  equals  weight  required  for  semi- 
porous  material. 


574         FIRE   PREVENTION   AND   FIRE   PROTECTION 


SAFE   LOADS  —  SEGMENTAL   ARCHES. 


Spans 
ft. 
and 
ins. 

Rise, 
ins. 
per  ft. 

4-in. 
arch, 
Ibs. 

6-in. 
arch, 
Ibs. 

8-in. 
arch, 
Ibs. 

10-in. 
arch, 
Ibs. 

Spang 
ft. 
and 
ins. 

Rise, 
ins. 
per  ft. 

4-in. 
arch, 
Ibs. 

6-in. 
arch, 

Ibs. 

8-in. 
arch, 
Ibs. 

10-in. 
arch. 
Ibs 

1 

702 

902 

1078 

1178 

f 

300 

386 

461 

504 

1 

920 

1184 

1414 

1545 

403 

518 

619 

677 

H 

1155 

1485 

1774 

1939 

li 

501 

645 

770 

842 

4  • 

if 

1353 

1740 

2079 

2272 

9  - 

H 

590 

758 

906 

990 

li 

1545 

1986 

2373 

2593 

If 

677 

871 

1041 

1137 

2 

1736 

2233 

2667 

2915 

2 

759 

977 

1167 

1275 

f 

616 

792 

946 

1034 

i 

283 

364 

435 

475 

812 

1044 

1247 

1363 

1 

380 

489 

584 

638 

li 

1020 

1313 

1568 

1713 

li 

472 

608 

726 

793 

4-6 

If 

1196 

1539 

1838 

2009 

9-b  • 

If 

561 

721 

862 

942 

l| 

1381 

1775 

2121 

2318 

l! 

639 

823 

983 

1074 

2 

1536 

1975 

2359 

2578 

2 

717 

923 

1102 

1204 

| 

551 

709 

847 

926 

i 

267 

344 

411 

449 

744 

957 

1143 

1249 

1 

359 

462 

552 

603 

6, 

li 

911 

1172 

1400 

1530 

10  , 

li 

447 

576 

688 

751 

l| 

1072 

1379 

1647 

1800 

l| 

531 

683 

816 

892 

if 

1238 

1592 

1902 

2078 

If 

610 

784 

937   1024 

2 

1379 

1773 

2118 

2315 

2 

683 

879 

1050 

1147 

} 

499 

641 

766 

837 

1 

244 

315 

376 

411 

672 

864 

1032 

1128 

1 

327 

421 

503 

550 

K  C 

U 

826 

1062 

1269 

1387 

11  . 

H 

404 

519 

621 

678 

o—  o 

l| 

984 

1266 

1512 

1652 

li 

479 

617 

737 

805 

H 

1119 

1439 

1719 

1879 

if 

551 

709 

847 

925 

2 

1258 

1619 

1933 

2113 

2 

617 

794 

948 

1036 

i 

455 

585 

699 

764 

! 

222 

285 

341 

372 

612 

788 

941 

1028 

i 

297 

383 

458 

500 

6. 

li 

753 

969 

1157 

1265 

12  . 

11 

370 

477 

569 

622 

If 

898 

1154 

1379 

1507 

if 

439 

566 

676 

738 

if 

1022 

1315 

1570 

1716 

if 

505 

649 

776 

848 

2 

1148 

1476 

1763 

1927 

2 

565 

727 

869 

949 

i 

428 

551 

658 

719 

1 

203 

261 

312 

341 

1 

562 

724 

864 

944 

1 

272 

351 

419 

458 

fi-6 

li 

701 

902 

1077 

1177 

1  0 

H 

339 

437 

522 

570 

ii 

823 

1058 

1264 

1382 

13  • 

1 

403 

519 

620 

677 

if 

947 

1218 

1455 

1590 

li 

463 

596 

712 

778 

2 

1055 

1358 

1622 

1772 

2 

521 

670 

801 

875 

i 

394 

508 

606 

662 

f 

186 

240 

287 

313 

i 

520 

669 

799 

873 

1 

253 

326 

390 

426 

7 

1} 

648 

834 

996 

1089 

H 

315 

406 

485 

530 

it 

762 

981 

1171 

1280 

14  • 

if 

374 

482 

575 

629 

if 

876 

1127 

1346 

1471 

if 

430 

553 

661 

722 

2 

983 

1264 

1510 

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2 

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619 

740 

808 

i 

366 

471 

563 

615 

i 

174 

225 

268 

293 

1 

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621 

741 

810 

i 

234 

302 

361 

394 

7-6 

li 

602 

774 

925 

1011 

H 

292 

377 

450 

491 

11 

715 

920 

1099 

1201 

15  • 

If 

347 

447 

534 

583 

H 

815 

1049 

1253 

1369 

if 

401 

515 

616 

673 

2 

915 

1176 

1405 

1536 

2 

449 

577 

690 

754 

I 

341 

439 

525 

573 

i 

162 

209 

249 

272 

457 

588 

703 

768 

1 

218 

281 

336 

367 

H 

562 

724 

864 

944 

li 

274 

353 

421 

460 

8  • 

If 

668 

859 

1026 

1122 

16  < 

H 

325 

419 

500 

546 

if 

767 

987 

1179 

1288 

ii 

374 

481 

575 

628 

2 

854 

1099 

1312 

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2 

420 

540 

645 

705 

i 

319 

411 

491 

536 

f 

151 

194 

232 

254 

1 

428 

551 

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719 

205 

265 

316 

345 

1J 

527 

678 

810 

885 

1^ 

256 

330 

394 

430 

o-O- 

li 

626 

806 

963 

1052 

17  < 

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304 

392 

468 

512 

if 

719 

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540 

590 

2 

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2 

393 

506 

605 

661 

TERRA-COTTA  FLOORS,  GIRDER  PROTECTIONS,  ETC.   575 

Soffit  Tile  are  discussed  in  later  paragraphs  "Beam  and  Girder 
Protections,"  etc. 

Tie-Rods.*  —  The  use  of  tie-rods  is  necessary  in  all  flat  and 
segmental  tile  arches,  to  take  up  the  lateral  thrust  due  to  unequal 
loading  on  the  different  bays. 

If  tie-rods  for  segmental  arches  are  properly  placed  —  that  is, 
within  the  lower  third  of  the  beam,  or  preferably  at  the  center 
of  the  skew  —  their  necessary  exposure  constitutes  a  serious 
objection  to  the  use  of  this  type  of  arch  unless  a  suspended 
ceiling  is  used.  Where  a  level  ceiling  is  not  employed,  the 
methods  of  protecting  the  tie-rods  against  attack  by  fire  are 
unsightly  and  unsatisfactory.  Special-shaped  tiles  are  sometimes 
used,  giving  a  paneled  effect  to  the  arches,  as  shown  in  Fig.  215. 


FIG.  215.  —  Segmental  Arch  with  Protected  Tie-rod. 


Owing  to  the  unsightliness  of  exposed  tie-rods,  and  the  diffi- 
culty and  expense  of  properly  protecting  them,  they  are  often 
moved  up  to  a  line  about  1|  inches  above  the  soffits  of  seg- 
mental arches  (as  shown  in  Fig.  213),  in  which  case,  especially 
if  the  loads  are  heavy  or  the  spans  long,  all  outside  spans  or 
spans  next  to  well  holes  should  be  provided  with  either  crossed 
or  forked  (7  *\)  tie  rods. 


Ceiling  Finish.  —  The  under  surface  of  tile  floor  arches  is 
usually  finished  by  applying  two  coats  of  plaster  and  one  coat  of 
skimming..  Many  forms  of  terra-cotta  floor  blocks  are  grooved 
or  "  scored"  before  being  burned,  in  order  to  afford  a  key  for  the 
plaster.  This  is  indicated  by  Figs.  189  and  190. 

If  irregularities  exist  in  the  trueness  of  the  ceiling,  they  may 
be  built  down  to  a  level  surface  when  the  brown  or  second  coat 
of  plaster  is  applied.  False-beam  effects  may  be  secured  by  the 
use  of  metal  furring,  as  described  in  Chapter  XXI. 

Floor  Finish.  —  Where  the  arches  do  not  extend  up  to  the 
tops  of  the  supporting  beams,  this  space  must  be  leveled  up  with 
concrete.  If  wood  floors  are  used,  nailing  strips  or  "  screeds" 

*  See  also  Chapter_XI,  page  333. 


576        FIRE   PREVENTION   AND   FIRE   PROTECTION 

must  be  placed  to  receive  the  flooring,  the  intervening  spaces 
being  also  filled  with  cinder  concrete. 

Nailing  strips  are  usually  made  of  a  dovetailed  shape,  about 
2J  inches  wide  at  the  top,  3|  inches  wide  at  the  bottom,  and 
2  inches  thick.  These  are  run  over  and  at  right  angles  to  the 
beams,  being  held  in  place  by  some  form  of  clip  which  secures 
them  to  the  beam  flanges. 

After  all  piping  or  wiring  which  is  intended  to  go  below  the 
flooring  is  in  place,  the  spaces  between  the  screeds  are  filled  with 
cinder  concrete.  This  should  never  be  omitted,  as  air-spaces 
under  the  flooring  will  largely  contribute  to  the  spread,  intensity, 
and  resultant  damage  of  fire.  This  was  well  illustrated  in  the 
Home  Life  Building  fire,  described  in  Chapter  VI.  In  this  case 
even  the  concrete  filling  between  the  beams  was  dispensed  with, 
resulting  in  the  failure  of  several  beams  and  the  complete  de- 
struction of  nearly  all  wood  flooring. 

The  importance  of  good  quality  cinder  "fill"  as  a  leveling 
between  screeds,  etc.,  has  been  pointed  out  in  Chapter  XI. 

If  a  double  flooring  is  used,  a  f-inch  under-flooring  is  first  laid 
on  the  screeds,  upon  which  is  placed  the  finished  floor.  If  only 
one  thickness  is  used,  IJ-inch  matched  stock  is  most  common. 
Another  method  is  to  lay  a  2-inch  plank  floor  directly  on  the 
beams,  secured  by  means  of  clips,  over  which  is  generally  placed 
a  finished  flooring.  The  height  of  the  finished  flooring  above  the 
beams  is  made  as  small  as  possible,  but  it  is  seldom  less  than  3 
inches. 

Wood  floors  are  gradually  being  eliminated  in  many  fire- 
resisting  buildings.  Floors  with  a  cement,  granolithic,  mosaic 
or  tile  finish  are  being  extensively  employed. 

Weather  and  Stain  Protection.  —  Terra-cotta  floors  should 
always  be  protected  against  rain  or  snow,  if  apt  to  be  followed  by 
freezing  and  thawing,  as  the  mortar  joints  will  be  injured.  This 
would  probably  result  in  a  later  deflection  of  the  arches.  The 
blocks  themselves  are  also  weakened  by  the  action  of  frost,  and, 
if  long  continued,  are  liable  to  crack  and  allow  the  falling  of  the 
arch. 

If  plastered  ceilings  are  to  be  used,  the  terra-cotta  work  should 
be  protected  against  the  smoke  or  soot  coming  from  hoisting 
engines  directly  beneath. 

Method  of  Setting.  —  For  the  erection  of  terra-cotta  arches 
wooden  centers  are  used.  In  the  eastern  states,  iron  clips,  about 


TERRA-COTTA  FLOORS,  GIRDER  PROTECTIONS,  ETC.   577 


FIG.  216.  —  Detail  of  Centers  for  Hollow 
Tile  Flat  Arches. 


2£  inches  by  J  inch  in  size,  are  first  hooked  around  the  upper 
flanges  of  the  I-beams,  and  from  these  are  suspended  f-inch 
diameter  hooks  or  rods,  with  a  thread  and  nut  at  the  top  for 
adjustment,  and  a  hook  at  the  bottom  to  support  the  wood 
stringers  which  run  at  ^ 

right  angles  to  the  beams. 
On  the  stringers  are  placed 
2-inch  planks,  dressed  on 
one  side  to  a  uniform  thick- 
ness, laid  close  together,  in 
a  direction  parallel  to  the 
beams.  These  planks  re- 
ceive the  terra-cotta  blocks 
(see  Fig.  216). 

In  adjusting  the  centers, 
a  sufficient  camber  should 
be  given  to  make  up  what- 
ever spring  there  may  be  to  the  stringers  during  the  time  of 
setting.  This  camber  is  usually  made  by  laying  upon  the 
stringers,  between  the  beams,  wood  strips  sawed  with  a  rise  of 
about  i  of  an  inch  per  foot. 

In  setting  the  tile  it  is  very  common  to  build  the  arches  in 
string  courses  on  the  beams,  first  setting  all  the  skews,  then  all 
the  lengtheners  and  finally  all  the  keys.  This  is  bad  practice, 
as  it  loads  the  center,  both  planks  and  stringers,  to  excess,  caus- 
ing too  great  a  deflection.  In  the  end-construction,  the  arches 
should  be  built  one  by  one,  each  being  complete  before  the  next 
is  started. 

Skews.  —  As  the  protection  of  the  lower  flanges  of  the  steel 
beams  is  of  vital  importance  in  case  of  fire,  great  care  is  necessary 
in  the  placing  of  the  skews  and  the  soffit  tile.  Among  builders 
generally,  'this  is  passed  by  without  due  attention.  It  is  cus- 
tomary, in  setting  a  skew  with  the  beam  protection  worked  on 
the  block,  to  spread  the  mortar  on  the  top  of  the  lower  flange, 
and  then  push  the  skew  in  place.  In  setting  the  skew  in  this 
manner  no  care  is  taken  to  see  that  the  bottom  of  the  beam  is 
given  any  room  in  which  to  expand  under  excessive  heat,  as  in 
most  cases  the  protection  on  the  skew  will  be  in  contact  with 
the  beam.  When  expansion  of  the  beam  does  occur,  the  beam 
protection  will  break  away  and  expose  the  steelwork. 

To  avoid  this,  the  distance  between  the  beam  protection  on 


578         FIRE    PREVENTION    AND    FIRE    PROTECTION 

the  skew  and  the  seat  of  the  skew  where  resting  on  the  lower 
flange  of  the  beam  should  be  considerably  larger  than  the  actual 
measurement  of  the  beam  flange  itself,  plus  the  space  required 
for  a  proper  mortar  bedding.  The  mortar  should  be  spread  as 
thinly  as  is  practicable  to  give  a  perfect  bedding  for  the  skew. 
If  set  in  this  manner,  the  protection  lip  on  the  skew  will  be  at 
some  distance  from  the  beam,  and  when  expansion  occurs  the 
protecting  flange  will  not  break  away. 

Soffit  Tile.  —  In  setting  skews  with  separately  applied  soffit 
tile,  the  same  care  is  necessary  to  prevent  the  latter  from  coming 
in  contact  with  the  beam.  The  soffit  tile  should  be  placed  on 
the  centering,  without  mortar.  They  should  be  of  sufficient 
width  to  come  in  contact  with  the  skews,  and  what  mortar  is 
used  in  setting  the  skews  should  be  high  up  on  the  beveled  lips, 
so  that  when  the  skews  are  placed  the  mortar  is  largely  at  the 
top  edges  of  the  soffit  tile,  forcing  them  rather  away  from  the 
beam  than  towards  it.  These  separate  soffit  tile  are  usually 
made  12  inches  long,  and  in  a  variety  of  widths  to  suit  the  differ- 
ent sizes  of  beams  used. 

In  securing  the  centers,  care  should  be  taken  to  see  that  suffi- 
cient room  is  left  between  the  top  of  the  center  and  the  bottom 
of  the  beam  to  permit  the  placing  of  the  soffit  tile  as  before 
described,  and  when  the  latter  are  in  position  the  center  should 
be  tightened  up  enough  to  hold  them  well  in  place,  but  not 
enough  to  break  them. 

As  the  skews  are  set,  the  beam  webs  should  be  thoroughly 
coated  with  mortar  as  a  protection  against  corrosion.  This 
coating  should  be  continuous,  without  voids. 

Lengtheners  and  keys  should  be  sufficiently  bedded  to  give  an 
even  bearing,  one  block  to  another.  All  joints  should  be  filled 
with  mortar,  especially  at  the  top.  The  blocks  must  be  in  close 
contact,  well  shoved  in  place.  In  setting  end-construction 
lengtheners,  special  care  is  necessary  to  see  that  they  are  placed 
to  a  true  line,  so  as  to  give  full  bearings  of  webs  to  webs.  They 
are  easily  placed  out  of  line,  either  sideways,  or  one  higher  than 
the  other,  thereby  weakening  the  construction.  If  a  space 
occurs  at  one  side  of  a  key,  a  solid  slab  of  tile  should  be  inserted, 
well  covered  with  mortar;  or,  if  the  opening  is  too  small  for  this, 
a  slab  of  slate  should  be  used.  Keys  should  never  be  forced  in 
place. 

Top  Coating.  —  The  tops  of  all  hollow-tile  arches,  whether  flat 


TERRA-COTTA   FLOORS,  GIRDER   PROTECTIONS,  ETC.       579 

or  segmental,  should  preferably  be  covered  with  a  coat  of  Port- 
land cement  mortar  at  least  |  inch  thick,  troweled  fairly  smooth. 
If  pipes  are  allowed  to  penetrate  the  arches,  such  holes  should 
be  carefully  pointed  up  after  the  work  is  finished.  This  practice 
will  make  the  arch  waterproof,  or  practically  so. 

Mortar.  —  All  hollow  tile  should  be  thoroughly  wet  before 
using,  especially  in  warm  weather,  as  otherwise  the  suction  of 
the  tile  will  take  the  water  from  the  mortar  too  freely,  causing 
the  mortar  to  lose  strength.  Hollow-tile  work  should  not  be 
set  when  the  water  or  mortar  will  freeze. 

For  mortar,  enough  lime  putty  should  be  added  to  Portland 
cement  mortar  to  make  it  trowel  smoothly.  Hot  lime  mortar 
should  never  be  used.  Pure  cement  mortar  is  too  short,  and  is 
apt  to  roll  off  the  tile  before  full  joints  are  obtained. 

Removal  of  Centers.  —  In  dry  weather  the  centers  should  re- 
main in  place  at  least  48  hours.  In  wet  weather  they  should 
remain  considerably  longer,  depending  upon  the  exposure  to 
moisture. 

Centering  Segmental  Arches.  —  Under  the  beams  are  hung 
stringers  made  of  plank  wide  enough  to  project  on  each  side 
beyond  the  beam  flanges,  thus  making  a  shelf  on  which  may  rest 
the  curved  centering.  These  usually  consist  of  2-inch  plank, 
cut  to  radius  along  the  top  edge,  and  placed  on  edge  at  intervals 
to  receive  6-inch  by  f-inch  boards,  forming  the  segmental  surface. 

Where  the  spans  are  variable,  but  with  the  same  rise  per  foot, 
it  is  best  to  make  the  centers  for  the  widest  spans.  These  can 
then  be  cut  away  at  the  sides  and  be  made  to  fit  the  shorter  spans. 

Details  Requiring  Careful  Inspection.  —  In  setting  any 
type  of  hollow-tile  floor-arch  construction,  great  care  must  be 
exercised  to  restrict  the  use  of  broken  or  imperfect  tile;  to  pre- 
vent carelessness  in  opposing  rib  to  rib  in  the  same  arch  ring;  to 
secure  properly  mortared  joints;  to  protect  properly  all  exposed 
portions  of  the  steel  framework,  and,  in  general,  to  obtain  uni- 
formly good  workmanship  in  all  details  of  setting. 

Defects  in  setting  are  often  hard  to  detect,  as  the  blocks  are 
laid  on  wooden  centering,  and  while  the  top  may  appear  to  fulfil 
all  conditions  of  good  workmanship,  the  bottom  may  look  very 
different  when  the  centering  is  removed.  The  architect  is  very 
apt  to  pass  over  such  defective  work,  owing  to  delay  if  replace- 
ment is  demanded,  and  the  excuse  of  " common  practice"  justi- 
fies the  results. 


580         FIRE    PREVENTION    AND    FIRE    PROTECTION 

The  great  carelessness  which  may  obtain  in  the  setting  of  tile 
arches  was  well  pointed  out  in  an  article  on  "  Hollow-tile  Fire- 
proofing  in  the  Park  Row  Syndicate  Building,"*  and  the  defects 
in  setting,  above  enumerated,  were  strikingly  illustrated  by  photo- 
graphic views  taken  throughout  the  building.  Such  defects  are 
due  to  injured  material  and  poor  workmanship,  rather  than  to 
the  nature  of  the  arch  material  itself;  and  as  all  of  these  faults 
can  be  corrected  by  a  more  careful  supervision  of  the  workmen, 
and  more  careful  handling  and  closer  inspection  of  the  material, 
such  inspection  and  care  become  of  great  importance. 

BEAM  AND  GIRDER  PROTECTIONS. 

Experience  in  Baltimore  Fire.  —  The  following  criticisms 
regarding  the  protections  of  beam  soffits  and  girders,  as  exhibited 
in  the  buildings  which  passed  through  the  Baltimore  conflagra- 
tion, are  from  the  " Conclusions"  given  in  the  report  of  the 
National  Fire  Protection  Association  Committee: 

The  covering  for  lower  flanges  of  beams  and  girders  should 
not  be  less  than  2  inches  thick,  and  should  not  be  held  by  exposed 
metal  clips,  nor  by  mortar  alone.  Wedge-shaped  flange  tile 
held  by  skewbacks  of  tile  arches  as  ordinarily  constructed  cannot 
be  depended  on,  owing  to  the  breaking  of  the  tile.  Shoe  tiles 
for  girders  are  also  unreliable  for  the  same  reason. 

The  protection  furnished  by  the  fire-protective  coverings 
on  the  lower  flanges  of  beams  and  girders  was  generally  unsatis- 
factory where  the  heat  was  of  more  than  usual  intensity.  The 
steel  work  at  these  points  was  almost  invariably  found  exposed. 

The  failure  of  this  protection  was  due  to  a  variety  of  causes, 
the  most  apparent  being  the  failure  of  the  sheet-metal  clips  used 
to  hold  the  flange  tile;  the  dropping  of  tile  which  was  only  held 
in  position  by  mortar;  the  breaking  off  of  the  skewbacks  with 
the  lower  web  of  the  tile  arches,  and  the  breaking  off  of  the  shoe 
tile  at  a  point  opposite  the  edges  of  the  flanges.  In  some  in- 
stances the  failure  of  shoe  tile  also  permitted  the  tile  protection 
to  the  web  plates  of  girders  to  fall  off. 

Supplementing  the  above,  numerous  illustrations  are  given  in 
the  text  of  the  report  showing  typical  or  individual  cases  of 
inadequate  beam  and  girder  protections  in  a  number  of  the 
buildings.  Some  of  these  details  are  reproduced  herewith  to 
show  how  poor  the  workmanship  really  was,  at  least  in  many 
instances.  They  will  well  serve  to  illustrate  how  fireproofing 
should  not  be  done. 

*  See  Engineering  News,  April  14,  1898. 


TERRA-COTTA   FLOORS,  GIRDER  PROTECTIONS,  ETC.       581 


Fig.  217  shows  the  protection  afforded  double  15-inch  I-beam 
girders  in  the  Continental  Trust   Company's  Building,   where 

/Wood  Floor  , 

x  Cinder' Concrete 


Plaster^  f        ^-Broken  Tile  - 

^Metal  Clips 

FIG.  217.  — Girder  Protection,  Continental  Trust  Go's.  Bldg.,  Baltimore  Fire. 

some  soffit  tile  were  supported  by  mortar  only.  Such  practice 
seems  inconceivable  in  a  structure  of  this  character,  if  erected 
by  reputable  contractors. 


"•Metal  Clips 


•Metal  Clip 


FIG.     218. — Girder    Protection,      FIG.     219. — Girder     Protection,     Union 
Maryland    Trust    Co.'s    Bldg.,  Trust  Co.'s  Bldg.,  Baltimore  Fire. 

Baltimore  Fire. 

Fig.  218  shows  the  fireproofing  of  the  regular  girders,  consist- 
ing of  two  24-inch  I-beams  between  columns,  in  the  Maryland 
r  Company's  Building,  and  Fig.  219  shows  a  girder  beam  in 


582 


FIRE    PREVENTION    AND    FIRE    PROTECTION 


the  Union  Trust  Company's  Building.  Both  of  these  details 
illustrate  the  use  of  poorly  designed  and  insufficient  soffit  tile, 
and  the  use  of  unprotected  metal  clips,  and,  in  Fig.  219,  the 
employment  of  wood  strips  in  combination  with  metal  clips. 
Fig.  220  is  of  a  typical  beam-soffit  protection  in  the  Calvert 


^Composition 

/•Wood  Strip 


Metal  Clip 


Plaster' 


FIG.  220.  —  Beam  Soffit  Protection,  Cal-     FIG.  221.  —  Roof  Beam  Protection, 
vert  Building,  Baltimore  Fire.  Maryland  Trust  Building,  Balti- 

more Fire. 

Building,  and  Fig.  221  a  typical  roof-beam  protection  in  the 
Maryland  Trust  Company's  Building,  both  illustrating  too  shal- 
low lips  on  the  skews  and  insufficient  thickness  for  soffit  tiles. 

Fortunately,  a  number  of  the  practices  condemned  in  the  report 
quoted  above  have  given  place,  in  good  work  at  least?  to  better 
methods,  as  will  be  pointed  out  in  following  paragraphs.  If  hol- 
low-tile arches  are  built  in  accordance  with  the  recommendations 
given  on  page  596,  and  if  beams  and  girders  are  protected  as 
described  below,  hollow-tile  floor  systems  will  undoubtedly  fulfil 
all  reasonable  demands. 

Terra-cotta  Beam  Protections.  —  Two  different  types  of 
side-construction  skews  have  previously  been  described,  viz., 
"lipped,"  and  " soffit"  (see  page  552).  End-construction  skews 
are  always  of  the  latter  type.  Of  the  two,  the  " soffit"  skew,  in 
the  author's  opinion,  is  decidedly  preferable  from  several  stand- 
points, but  especially  as  regards  the  protection  afforded  the 
beams.  "Lipped"  skews  are  more  easily  cracked  or  broken  in 
transportation,  handling  and  setting,  thus  increasing  the  chance 
of  imperfect  blocks  being  used;  besides  which,  even  if  only 
sound  and  perfect  tile  are  used,  failure  is  more  apt  to  result  to 
the  lipped  skew  in  time  of  fire,  for  the  reason  that  any  flange  or 
lip  projecting  from  the  main  body  of  a  terra-cotta  block  — 


TERRA-COTTA   FLOORS,  GIRDER  PROTECTIONS,  ETC.       583 


whether  structural  or  ornamental  —  is  apt  to  develop  internal 
stresses  at  the  junction  point  in  drying  and  burning,  thus  render- 
ing the  block  more  liable  to  failure  under  severe  heat  at  such 
point. 

Soffit  tile  should  never  be  less  than  2  inches  thick,  whether 
porous,  semi-porous  or  hard.  They  are  usually  made  solid, 
though  some  factories  make  them  hollow.  The  former  are  pref- 
erable, as  solidity  of  material  is  of  more  consequence  than  air- 
spaces of  doubtful  value.  They  are  generally  made  as  shown 
in  Fig.  222,  with  the  top  surface  hollowed  out  about  one-half 


VNo  Mortar 

FIG.  222.  —  Detail  of  2-in.  Soffit  Tile 
Beam  Protection. 


FIG.  223.  —  Detail  of  Beam  Protec- 
tion with  Shoe  Tiles. 


inch.  This  is  in  order  that  only  the  edges  of  the  tile  may  come 
in  contact  with  the  beam,  so  that  warping  or  irregularities  in  the 
slabs  would  not  cause  breakage  in  applying  the  skews,  or  in 
tightening  up  the  centering.  No  mortar  is  placed  between  the 
soffit  tile  and  the  under  side  of  the  beam,  but  the  tile  are  held  in 
place  by  the  bevels  of  the  joints  and  the  mortar  in  those  joints. 

In  view  of  the  illustrations  previously  given  showing  details 
employed  in  some  of  the  Baltimore  buildings,  it  is  not  to  be 
wondered  at  that  the  National  Fire  Protection  Association  Com- 
mittee reported  that  "  wedge-shaped  flange  tile  held  by  skew- 
backs  of  tile  arches  as  ordinarily  constructed  cannot  be  depended 
on."  But  if  soffit  tile  are  made  2  inches  thick  of  solid  porous 
terra-cotta,  and  if  they  are  carefully  fitted  in  between  2-inch 
beveled  lips  on  the  skews,  the  beveled  joints,  if  set  in  good 
cement  mortar,  will  prove  ample  support  for  even  very  severe 
test  conditions. 

A  method  sometimes  employed  with  end-construction  skews 
is  shown  in  Fig.  223,  while  a  channel  at  a  well  opening  is  illus- 
trated in  Fig.  224. 


584 


FIRE   PREVENTION   AND   FIRE   PROTECTION 


If  it  is  desired  to  make  assurance  doubly  sure,  wire  netting 
may  be  wrapped  around  the  soffit  tile  and  the  lower  flange  of 
the  beam,  before  the  skews  are  placed,  as  shown  in  Fig.  225. 


Metal 
Clips 


FIG.  224.  —  Detail  of  Channel 
Protection. 


ire  Netting 


FIG.  225.  —  Detail  of  2-in.  Soffit  Tile 
and  Wire  Netting. 


This  method  has  been  followed  in  some  instances,  and  the  prac- 
tice should  be  more  general. 

Floor  beams  which  project  below  the  ceiling  line  are  classed 
with  girders,  and  methods  of  protection  are  considered  under 
the  following  heading. 

Terra-cotta  Girder  Protections.  —  The  importance  of  ade- 
quately protecting  girders  has  previously  been  pointed  out. 
Tile  coverings  should  never  be  less  than  2  inches  thick,  preferably 
of  porous  material,  and  solid  when  used  in  slab  form.  The  pro- 
tection should  be  as  nearly  self-supporting  as  possible.  Girders 
carrying  very  heavy  loads,  plate-  and  box-girders,  and  those  pro- 
jecting below  the  ceiling  lines,  require  special  attention. 


9'' — J 


Fia.     226.  —  Single     I-Beam 
Girder  Protection. 


Fia.    227.  —  Double  I-Beam  Girder  Pro- 
tection. 


The  National  Code  requires  the  exposed  sides  of  all  girders  to 
be  protected  by  not  less  than  4  inches  of  suitable  materials,  and 
flanges  by  not  less  than  2  inches. 


TERRA-COTTA    FLOORS,  GIRDER   PROTECTIONS,  ETC.       585 


1.  Girders  which  do  not  project  below  the  ceiling.  The  method 
of  protecting  a  single  I-beam  girder  running  parallel  to  the  cells 
in  an  end-construction  or 
combination  arch  is*  shown 
in  Fig.  226,  while  double 
beams,  placed  9  inches  cen- 
ters, under  the  same  condi- 
tions, are  shown  in  Fig.  227. 
A  single  beam,  parallel  to 
the  arch  voids  on  one  side, 
and  bounding  a  well-room  on 

the  Opposite  Side,  is  shown  in  FlG.  228.  _  s^l-Beam  Girder  Protec- 
Flg.     228.       Double      I-beam  tlon  at  Well-room, 

girders,  spaced  20  inches  or 

more  on  centers,  should  be  fireproofed  as  shown  in  Fig.  229. 
In  all  of  these  cases,  the  girder  protections  must  be  set  with 
the  arches,  except  in  the  case  of  Fig.  228,  where  the  girder  flanges 
and  well-room  side  may  be  covered  later. 


FIG.  229.  —  Double  I-Beam  Girder  Protection. 


The  method  of  protecting  the  bottom  flanges  in  Figs.  226  and 
227  is  not  entirely  satisfactory,  as  metal  clips  form  the  only 
means  of  supporting  the  soffit  tile.  These  figures,  however, 
represent  rather  unusual  practice,  as  such  girders  are  generally 
made  deeper  than  the  beams,  and  projecting  below  the  ceiling 
line. 

2.  Girders  projecting  below  the  ceiling  are  especially  liable  to 
failure  under  severe  fire  and  water  test,  for  reasons  previously 
enumerated. 

Fig.  230  illustrates  a  typical  girder  protection  as  used  in  the 
United  States  Court  House  and  Post  Office,  Los  Angeles,  Cal. 
The  lower  flange  of  the  girder  I  is  protected  by  means  of  "clip 


586         FIRE    PREVENTION    AND    FIRE    PROTECTION 

tile"  or  "shoe  tile,"  which  are  now  generally  used  for  single 
beams  or  girders  projecting  below  the  floor-arch  construction. 
For  small  sizes  of  beams  these  clip  tile  should  preferably  be  made 


FIG.  230.  —  Single  I-Beam  Girder  Protection,'  U.  S.  Court  House  &  P.  O., 
Los  Angeles,  Cal.  j 

solid,  but  for  large  sizes  they  are  usually  made  hollow.     They 
should  preferably  be  made  of  porous  or  semi-porous  material, 


Floor 


Arch 


Fio.  231.  —  Single  I-Beam  Girder  Protection,  Cadillac  Automobile 
Factory,  Detroit. 

and  not  less  than  2  inches  thick  where  bearing  against  the  edge 
of  the  beam  flange  (see  also  Fig.  241). 

Fig.  231  shows  a  typical  floor  girder,  parallel  to  end-construc- 
tion arches,  as  protected  in  the  Cadillac  Automobile  Factory, 
Detroit. 


TERRA-COTTA    FLOORS,  GIRDER   PROTECTIONS,  ETC.       587 


Fig.  232  shows  the  best  method  of  protecting  double  I-beam 
girders  when  spaced  less  than  18  inches  on  centers,  and  Fig.  233 
when  placed  18  inches  or  over  on  centers. 


Clip- 


10* 

1 


Clip 


.SECTION  OF 
SOFFIT  TILE 

FIG.   232.  —  Double  I-Beam  Girders  projecting  below  Ceiling. 

A  single  I-beam  girder  supporting  segmental  arches,  as  used 
in  the  Wanamaker  Store  Building,  New  York,  is  shown  in  Fig.  234. 
See  also  Figs.  239  and  240,  Chapter  XVIII. 


FIG.  233.- 


-  Double  I-Beam  Girders  project- 
ing below  Ceiling. 


FIG.  234.  —  Single  I-Beam 
Girder  supporting  Seg- 
mental Arches. 


Metal  Clips.  —  Unprotected  or  poorly  protected  metal  clips 
for  the  support  of  soffit  tile,  etc.,  should  be  unnecessary  in  prop- 
erly designed  and  executed  work.  They  have  been  invented 
and  used  by  contractors  for  fireproofing  work  as  a  convenient 
and  cheap  substitute  for  self-supporting  shapes  and  combina- 
tions, as  have  been  illustrated  above.  This  is  not  to  say  that 
metal  clips  should  never  be  used,  as  sometimes  there  seems  to  be 
no  satisfactory  alternative,  as,  for  instance,  in  such  cases  as  shown 


588         FIKE   PREVENTION   AND   FIRE   PROTECTION 

in  Figs.  226  and  227,  but  when  used  they  should  invariably  be 
amply  protected.  Metal  clips  are  required  by  some  building 
laws  for  beam-  and  girder-soffit  protections,  but  a  little  care  in 
their  design  and  use  will  easily  make  them  an  added  precaution, 
instead  of  the  sole  reliance. 

Protection  of  Plate-  and  Box-Girders.  —  Practically  the 
same  principles  as  are  used  in  the  protection  of  beam  girders  are 
applicable  to  either  plate-  or  box-girders,  and  the  same  require- 
ments of  adequate  thickness  in  the  terra-cotta  blocks  and  me- 
chanical fastening  to  insure  stability  must  obtain  with  even 
greater  care,  due  to  the  increased  loads  usually  borne  by  such  i 
members. 

An  exceptionally  efficient  girder  protection,  as  used  in  the 
Government  Printing  Office,  Washington,  D.  C.,  is  illust rated  j 
in  Fig.  47,  Chapter  XI.  This  same  method  of  wrapping  shoe  tile 
or  clip  tile  with  wire  netting,  will,  as  in  the  case  of  soffit  tile, 
provide  greatly  increased  efficiency. 

Figs.  242  and  243,  Chapter  XVIII,  show  terra-cotta  protec- 
tions for  plate-  and  box-girders  respectively. 

FIRE  AND  LOAD  TESTS  OF  TERRA-COTTA  FLOORS. 

Denver  (Colo.)  Tests.  —  Made  in  Denver,  Colo.,  in  Decem- 
ber, 1890,  for  the  Denver  Equitable  Building  Company,  under 
the  supervision  of  Messrs.  Andrews,  Jaques  and  Rantoul,  archi- 
tects. This  series  of  public  tests  formed  one  of  the  earliest,  as 
well  as  one  of  the  most  valuable  series  of  competitive  tests  ever 
undertaken. 

When  bids  for  executing  the  fireproofing  contract  for  this 
building  were  opened,  it  was  found  that  three  competitors  had 
figured  on  the  work,  two  of  whom  estimated  on  furnishing  floor 
arches  of  hard  tile,  side-construction,  while  the  third,  at  the 
highest  price,  figured  on  furnishing  arches  of  porous  tile  on  a  new 
principle,  now  well  known  as  the  "  end-construction "  method 
In  order  that  the  relative  qualities  of  the  different  systems  mighl 
be  compared,  the  architects  decided  to  institute  a  series  of  tests 
the  conditions  including: 

A  —  still  load,  increased  to  failure  of  arch; 

B  —  shocks,  repeated  to  failure  of  arch; 

C  —  fire  and  water  test,  alternating  until  arch  was  destroyed 

D  —  continuous  fire  of  high  heat,  until  arch  was  destroyed. 


TERRA-COTTA    FLOORS,  GIRDER   PROTECTIONS,  ETC.       589 

Twelve  arches  in  all  were  tested  —  three,  or  one  for  every 
competitor,  under  every  condition.  The  arches  were  10  inches 
in  depth,  built  between  I-beams  5  feet  centers. 

Still-load  Test.  —  The  "Lee"  or  end-construction  arch,  sus- 
tained a  final  load  of  15,145  pounds  for  two  hours,  the  deflection 
being  .065  of  a  foot.  The  heaviest  load  sustained  by  a  side- 
construction  arch  was  8574  pounds. 

Drop  Test.  —  The  blows  were  given  by  dropping  upon  the 
arches  a  piece  of  Oregon  pine,  12  inches  square  and  4  feet  long, 
weighing  134  pounds,  from  a  height  of  6  feet.  Both  of  the  side- 
construction  arches  were  shattered  at  the  first  blow,  while  the 
end-construction  arch  stood  up  to  the  eleventh  drop  from  a 
height  of  8  feet. 

Fire  and  Water  Test.  —  One  of  the  side-construction  arches 
was  destroyed  by  three  applications  of  water  with  a  fire  tem- 
perature of  1300  degrees,  the  other  being  very  badly  shattered 
after  fourteen  applications  of  water.  The  end-construction  arch 
was  given  eleven  applications,  and  at  the  end  of  twenty-three 
hours  was  practically  uninjured,  as  it  required  eleven  blows  from 
the  ram  used  in  the  drop  test  to  break  the  arch  down. 

Continuous  Fire  Test.  —  Of  the  two  side  arches,  one  failed  com- 
pletely after  a  continuous  fire  of  twenty-four  hours,  while  the 
other  arch  stood,  but  was  unable  to  carry  a  load  of  300  pounds 
per  square  foot.  The  end-construction  arch'  supported  a  weight 
of  bricks  of  12,500  pounds  on  a  space  3  feet  wide  in  the  middle 
of  the  arch,  after  a  continuous  fire  for  twenty-four  hours. 

The  results  of  the  Denver  tests  have  never  been  questioned, 
as  they  were  rendered  all  the  more  emphatic  by  testing  two 
separate  sets  of  hard-tile  side-construction  arches,  with  nearly 
identically  poor  results,  as  compared  with  the  third  satisfactory 
test  of  porous-tile  arches  of  end-construction.  Two  important 
facts  were  here  established  beyond  question  —  namely,  that 
hard  tile  is  brittle,  unable  to  stand  fire  or  water  tests  and  is, 
therefore,  very  inferior  to  porous  tile;  and  secondly,  that  the 
side-construction  method  of  tile-floor  construction  cannot  be 
favorably  compared  with  the  end-construction  type  as  to 
strength. 

New  York  Building  Department  Tests.  —  A  general  de- 
scription of  the  fire  and  water  tests  inaugurated  by  the  New  York 
Building  Department,  and  present  requirements  as  to  fire-re- 
sisting floors  demanded  by  that  department,  have  previously 


590         FIRE    PREVENTION    AND    FIRE    PROTECTION 

been  given  in  Chapter  V.  Some  of  the  more  important  tests 
of  terra-cotta  floors  included  in  that  series  are  as  follows: 

Porous  Terra-cotta  Arch.  —  The  arches  were  made  of  10-inch 
end-construction,  porous  terra-cotta  blocks,  leveled  up  to  the 
tops  of  beams  with  a  one-inch  filling  of  cement  mortar.  The 
beam  flanges  were  protected  by  soffit  tile  held  in  position  by 
beveled  lips  on  the  skewbacks.  Two  of  the  bays  were  plastered 
on  the  soffit,  while  one  bay  was  left  with  the  tile  exposed. 

Duration  of  fire  test,  9.00  A.M.  to  3.00  P.M.  At  2.54  P.M.  cast- 
iron  was  placed  in  the  kiln  and  melted  in  two  minutes.  Maxi- 
mum deflection,  2.16  inches. 

During  the  fire  test  all  of  the  plaster  dropped  from  the  walls 
of  the  kiln.  Upon  the  application  of  water  all  of  the  ceiling 
plaster  fell.  About  35  per  cent  of  the  arch  blocks  were  cracked, 
the  lower  sections  of  some  blocks  having  broken  off  to  a  depth 
of  about  3J  inches.  One  block  was  hanging  half  out  of  the  arch. 
All  of  the  soffit-protection  pieces  had  fallen  except  very  near  the 
walls  of  the  kiln. 

The  final  load  of  600  pounds  per  square  foot  gave  a  deflection 
0.22  inch. 

Porous  Terra-cotta  Arch.  Second  Test.  —  Twenty  days  after 
the  final  loading  of  the  arch  described  above,  the  supporting 
beams  were  shored  up  to  prevent  deflection  and  the  central  bay 
of  the  floor  was  loaded  up  to  611  pounds  per  square  foot.  On 
following  days  this  load  was  gradually  increased  to  1175  pounds 
per  square  foot.  The  deflection  due  to  this  load  was  0.84  inch. 
The  load  was  then  shifted  to  cover  an  area  of  9  feet  by  4  feet,  the 
total  load  being  1960  pounds  per  square  foot.  The  deflection 
was  2.2  inches.  This,  added  to  the  permanent  set  which  existed 
previous  to  loading,  gave  a  total  deflection  of  3.41  inches. 

The  arch  was  still  intact  under  this  load. 

Hard-burned  Terra-cotta  Arch. — The  blocks  were  10  inches 
deep,  side  construction,  projecting  1J  inches  below  the  I-beams. 
They  were  furnished  by  the  Raritan  Hollow  and  Porous  Brick 
Company.  Each  arch  ring  consisted  of  two  lipped  skewbacks, 
four  lengtheners  and  one  key  block.  The  blocks  were  laid  in 
cement  mortar,  J-inch  joints.  The  ceiling  was  plastered  two 
coats. 

Duration  of  fire  test,  10.22  A.M.  to  3.22  P.M.  Maximum  tem- 
perature 2050  degrees.  Maximum  deflection,  1.84  inches. 

At  the  conclusion  of  the  test  about  all  of  the  plaster  was  gone, 


TERRA -COTTA    FLOORS,  GIRDER   PROTECTIONS,  ETC.       591 

even  where  not  reached  by  the  water.  A  considerable  portion 
of  the  tile  was  broken  by  the  effects  of  the  water,  causing  the 
lower  parts  to  fall.  Many  of  the  skewback  lips  had  broken 
directly  under  the  beam  flanges,  leaving  the  latter  partly  exposed. 

The  final  load  of  600  pounds  per  square  foot  caused  a  center 
deflection  of  0.22  inch. 

British  Fire  Prevention  Committee  Test.  —  In  June, 
1905,  a  fire  and  water  test  was  made  in  London  by  the  British 
Fire  Prevention  Committee  on  "a  fire-resisting  floor  constructed 
of  semi-porous  terra-cotta  blocks  with  steel-wire  reinforcement, " 
built  by  the  National  Fire  Proofing  Company.  The  construction 
was  virtually  the  same  as  the  "New  York"  reinforced  arch, 
previously  described.  The  roof  of  the  test  house  was  covered 
with  four  bays  which  were  supported  by  10-inch  beams  and 
channels  —  one  bay  was  of  8-inch  blocks,  span  7  feet,  7J  inches; 
one  of  6-inch  blocks,  span  6  feet;  one  of  8-inch  blocks,  span  7  feet, 
6  inches;  one  of  8-inch  blocks,  span  1  foot,  1^  inches.  Semi- 
porous,  end-construction  blocks  and  side-construction  skews 
were  used  with  |-inch  mortar  joints,  in  which  were  embedded 
wire  reinforcement  trusses  1}  inches  deep,  similar  to  that  illus- 
trated on  page  560,  except  that  the  horizontal  wires  were  doubled 
and  interlaced,  instead  of  single  as  now  generally  used.  Separate 
soffit  tile  1J  inches  thick  protected  the  lower  flanges  of  the  beams. 
The  floor  was  loaded  with  bricks  equal  to  a  distributed  load  of 
280  pounds  per  square  foot. 

The  fire  test  was  of  four  hours'  duration,  —  maximum  tem- 
perature attained  1880°  F.,  —  after  which  water  was  applied  at 
a  pressure  of  65  pounds  through  a  J-inch  nozzle  for  5  minutes. 
The  following  observations  were  made  after  the  test : 

The  surface  of  the  top  of  the  floor  showed  a  slight  crack 
at  the  northwest  corner. 

The  plaster  on  the  soffit  of  the  floor  was  washed  off  where 
struck  by  the  jet.  The  remainder  was  friable  and  covered  with 
cracks. 

The  semi-porous  terra-cotta  blocks  forming  the  floor  were 
intact. 

There  was  no  permanent  deflection  of  the  floor  after  the 
removal  of  the  load. 

The  fire  had  not  passed  through  the  floor.* 

The  photographs  accompanying  the  report  show  that  neither 
[     arch  blocks  nor  soffit  tile  were  either  damaged  or  loosened. 
*  See  "Red  Book"  No.  96,  British  Fire  Prevention  Committee. 


592         FIRE    PREVENTION    AND    FIRE    PROTECTION 

Terra-cot ta  Groined  Arch,  constructed  by  the  National 
Fire  Proofing  Company,  tested  by  Prof.  Woolson,  1904. 

The  floor  tested  constituted  the.  floor  of  the  test  building. 
It  was  constructed  by  forming  a  groined  arch  of  6-inch  hollow 
tile  between  girders  with  a  rise  of  17  inches  at  the  crown.  Above 
the  tile  was  a  concrete  filling  of  about  4  inches  over  the  crown 
and  18  inches  at  the  haunches.  The  arches  were  sprung  from 
the  corners  of  the  rectangular  floor  space  instead  of  the  sides, 
thus  throwing  the  greatest  thrust  to  the  corners  where  the  frame- 
work could  best  resist  the  load. 

For  purpose  of  reinforcement,  two  8-inch  I-beams  were  put 
in  between  each  pair  of  girders  at  the  middle,  meeting  in  the 
center  of  the  floor  span.  These  beams  were  cambered  to  the 
curvature  of  the  arch  and  divided  the  test  floor  into  four  equal 
parts.  They  were  encased  by  the  floor  tile. 

The  construction  was  practically  a  reproduction  of  one  unit 
of  the  floor  system  used  in  the  new  Pittsburgh  Terminal  Ware- 
house and  Transfer  Company,  in  which  there  are  800,000  square 
feet  of  floor  space  all  divided  into  spans  20  feet  X  22  feet  the 
same  as  this.  .  .  . 

The  concrete  "fill"  was  mixed  in  the  proportions  of  1  Port- 
land cement,  3  river  sand  and  6  gravel.  The  tile  ceiling  was 
given  a  protective  coating  of  one  inch  of  cement. 

The  purpose  of  the  test  was  to  determine  the  effect  of  a 
continuous  fire  below  the  floor  for  four  hours  at  an  average  tem- 
perature of  1700°  F.,  the  floor  carrying  at  the  same  time  a  dis- 
tributed load  of  270  pounds  per  square  foot.  At  the  end  of  the 
four  hours  the  under  side  of  the  floor  (or  ceiling)  while  still  red 
hot  was  to  be  subjected  to  a  l|-inch  stream  of  cold  water  at  short 
range  under  60  pounds'  pressure  for  ten  minutes.  Deflection  of 
floor  to  be  measured  continuously  during  the  test.  .  .  . 

The  cement  coating  on  the  ceiling  began  to  blow  off  about 
ten  minutes  after  the  fire  started,  and  a  considerable  portion  of 
it  fell  before  the  expiration  of  the  test.  The  roof  was  covered 
with  a  load  of  hollow  tile  several  feet  deep,  making  it  impossible 
to  ascertain  whether  any  cracks  developed  there  or  not.  As  the 
roof  was  in  compression  in  all  parts,  and  the  deflections  recorded 
were  very  small,  it  is  not  likely  that  cracks  did  occur  there. 

After  application  of  the  water,  it  was  found  that  the  cement 
coating  was  gone,  and  the  tile  exposed  where  the  water  struck 
the  ceiling,  but  the  tile  appeared  to  be  in  perfect  condition  with  no 
cracks  or  broken  parts.  .  .  . 

The  floor  was  subsequently  loaded  to  1000  pounds  per 
square  foot  with  a  maximum  deflection  of  1J  inches.* 

Guastavino  Floor  Construction  (New  York  Building  De- 
partment Test.)  —  The  brick  walls  of  the  kiln  in  this  case  were 
corbeled  out  6  inches,  and  a  rectangular  horizontal  iron  frame 

*  Extracts  from  report,  "Fire  Series  No.  160,"  by  Ira  H.  Woolson,  E.  M. 


TERRA-COTTA    FLOORS,  GIRDER   PROTECTIONS,  ETC.       593 

was  built  into  the  upper  portion  of  the  kiln  walls  to  take  the 
thrust  of  the  dome.  This  system  required  no  intermediate  floor 
beams.  The  dome  consisted  of  three  successive  courses  of  flat 
fire-clay  tiles,  which  sprung  from  the  side  walls  with  a  rise  at  the 
center  of  10  per  cent,  of  the  greatest  span.  The  tiles  were  6  inches 
wide,  12  inches  to  18  inches  long  and  J  inch  to  1  inch  in  thick- 
ness, being  laid  in  cement  mortar.  The  construction  was  built 
on  a  wooden  center.  Two  kinds  of  floor  surfacing  were  used. 
In  one  half,  brick  ribs  extended  over  the  dome,  supporting  a 
double  course  of  horizontal  flat  tile,  which  received  the  finished 
floor.  In  the  other  half,  cinder  concrete  filling  was  used,  with 
embedded  nailing  strips.  Portions  of  the  ceiling  soffit  were 
plastered,  and  some  spaces  of  tile  were  left  exposed. 

The  initial  loading  gave  a  center  deflection  of  0.017  inch. 
.  Duration  of  fire  test,  9.15  A.M.  to  3.18  P.M.  Maximum  tem- 
perature 2525  degrees.  Maximum  deflection,  0.71  inch. 

Nearly  all  of  the  plaster  fell  early  in  the  fire  test,  but  before 
the  application  of  water  no  cracks  had  developed  in  the  ceiling, 
and  no  tile  had  fallen.  During  the  water  test,  portions  of  the 
lower  course  of  tile  fell  in  pieces,  due  to  the  sudden  contraction. 
One  I-beam,  supporting  a  corner  smoke  flue,  became  exposed. 
It  was  noticed  that  the  center  of  the  dome  rose  gradually  under 
the  influence  of  the  applied  heat,  which  caused  the  expansion 
of  the  masonry  in  the  dome  construction.  The  greatest  elevation 
was  0.71  inch. 

The  final  loading  of  600  pounds  per  square  foot  gave  a  center 
deflection  of  0.195  inch. 

Behavior  of  Hollow-tile  Arches  in  Actual  Fires.  —  San 
Francisco  Conflagration.  —  Factors  which  contributed  to  make 
the  San  Francisco  experience  of  doubtful  value  as  regards  fire 
tests  of  hollow-tile  constructions  have  previously  been  enumer- 
ated. Such  factors  were:  the  use  of  hard-burned  material  only, 

—  see  page  237,  —  and  poor  workmanship  —  see  page  323.     To 
these  should  be  added  the  uncertainty  as  to  the  amount  of  dam- 
age done  to  hollow-tile  constructions  by  the  earthquake.     The 
wrenching  of  the  buildings  by  the  earthquake  shocks  opened 
many  of  the  joints  in  such  constructions,  and  largely  destroyed 
the  binding  qualities  of  the  mortar.     Thus  in  the  Mills  Building 

—  an  example  of   damaged   hollow-tile   floors  often  quoted  — 
unmistakable  evidence  went  to  show  that  the  mortar  joints  in 
the  terra-cotta  floors,  etc.,  were  started  by  the  earthquake.     The 


594         FIRE    PREVENTION    AND    FIRE    PROTECTION 

mortar  was  disintegrated  by  the  fire,  and  great  damage  to  the 
arches  resulted.  The  same  effects  were  noticeable  in  other 
buildings.* 

Hence,  in  arriving  at  conclusions  concerning  the  behavior  of 
hollow-tile  arches  in  actual  fires,  the  author  will  eliminate  all 
reference  to  San  Francisco  buildings. 

Fires  in  Individual  Buildings  described  in  Chapter  VI,  in  which 
the  fire  tests  of  hollow-tile  arches  are  of  importance,  may  be 
summarized  as  to  such  tests  as  follows: 


•sj 

a 

L 

bJO 

Building. 

"8,2 

8 

!j 

a 

Condition. 

Q 

s 

8 

6 

In. 

Chicago  Athletic  Club  .  . 
Home  Store,  first  fire.  .  . 

'9 

Porous 
Hard 

End 
Side 

Flush 
Paneled 

Moderate  damage. 
Large  damage. 

Considerable  damage 

Home  Office  Building.  .  . 

9 

Porous 

End 

Paneled 

.    to  paneled  skews. 
Ceilings  slightly  dam- 

Home  Life  Building.  .  .  . 
Home  Store,  second  fire. 

10 
15 

Hard 
Porous 

Side 
End 

Paneled 
Paneled 

Moderate  damage 
Moderate  damage 

Granite  Building 

12 

Porous 

End 

Flush 

Considerable  damage 

Baltimore  Buildings. —  Similar  conditions  regarding  the  hollow- 
tile  floor  arches  in  the  Baltimore  buildings  —  omitting  from 
consideration  the  Equitable  Building  where  the  floors  were 
practically  a  total  loss  —  may  be  summarized  as  follows : 


13  2J 

3 

4 

1 

c«     0> 

°^TS 
|1| 

C3 
§g 

Building, 

11 

1 

£  fi 

(E    O 
§'£ 

1 

fell 

'SI 

§ 

«  « 

X 

O 

O 

£^ 

O 

In. 

Herald... 

12 

Sem  -porous 

End 

Paneled 

50 

Large  damage 

Union  Trust  

10 

Sem  -porous 

End 

Paneled 

40 

Large  damage 

Calvert  

15 

Porous 

End 

Flush 

7.5 

Little  damage 

Maryland  Trust  

9 

Sem  -porous 

End 

Paneled 

* 

Large  damage 

Continental  Trust 

16 

Sem  -porous 

End 

Flush 

* 

Little  damage 

Merchants'  Nat.  Bank  . 

10 

Sem  -porous 

End 

Flush 

* 

Excellent 

Chesapeake  &  Potomac  . 

12 

Porous 

Side 

Flush 

* 

Excellent 

*  Floor-  and  roof-arch  damage  not  estimated  separately  in  adjusted  fire  loss. 

This  showing  of  hollow-tile  arches  in  the  Baltimore  buildings 
was  commented  on  in  the  report  of  the  National  Fire  Protection 
Association  as  follows: 


*  See  Professor  Soute  in  Bulletin  No.  324,  page  148. 


TERRA-COTTA  FLOORS,  GIRDER  PROTECTIONS,  ETC.   595 

This  and  previous  fires  have  clearly  demonstrated  that 
substantially  constructed  floor  arches  made  of  hollow  terra-cotta 
tile  generally  stand  up  and  support  the  loads  to  which  they  are 
subjected.  They  have,  however,  failed  to  accomplish  all  that 
was  expected  of  them  on  account  of  the  breaking  off  of  a  large 
portion  of  the  lower  webs  of  the  arches,  necessitating  extensive 
repairs.  .  .  . 

Most  of  the  terra-cotta  tile  used  in  the  Baltimore  buildings 
was  designated  as  semi-porous,  but  considerable  variation  in  the 
density  was  noted.  Porous  tile  was  found  in  only  a  few  cases. 
The  results  indicate  that  there  is  no  great  preference,  so  far  as 
fire-resistive  qualities  go,  between  any  of  the  grades  of  such  tile 
used,  all  alike  permitting  the  lower  face  of  the  arch  to  break  off 
where  the  heat  was  most  intense.  The  breaking  of  the  lower 
face  of  the  terra-cotta  tile  in  the  Baltimore  buildings  where  no 
water  was  used  was  apparently  the  same  as  in  previous  fires 
where  such  tile  has  been  subjected  to  both  fire  and  water. 

In  the  opinion  of  the  writer,  who  made  a  critical  examination 
of  all  of  the  prominent  buildings  destroyed,  immediately  after 
the  Baltimore  fire,  the  above  conclusions  should  have  been  qual- 
ified in  one  respect  and  modified  in  another.  The  statement, 
regarding  "the  breaking  off  of  a  large  portion  of  the  lower  webs 
of  the  arches/'  would  seem  to  be  too  sweeping.  Considering 
the  test  that  these  buildings  underwent,  a  small  percentage  only 
of  the  webs  fell  off,  taking  the  buildings  as  a  whole.  Also  the 
statement  that  no  preference  in  fire-resisting  qualities  existed  be- 
tween the  different  grades  of  tile  is,  in  the  opinion  of  the  writer, 
unwarranted.  Thus,  of  the  seven  buildings  enumerated  above, 
five  contained  floor  arches  of  semi-porous  tile,  and  two  of  porous. 
Of  the  five,  two  only  made  a  creditable  showing,  viz.,  the  Conti- 
nental Trust  Building,  where  particularly  deep  arches  were  used, 
and  the  Merchants'  National  Bank,  where  a  most  excellent  show- 
ing was  made,  largely  due  to  heavy  webs  in  the  arch  blocks.  Of  the 
two  buildings  containing  porous  tile  arches,  namely,  the  Calvert 
and  the  Chesapeake  and  Potomac  Buildings,  both  gave  remark- 
able demonstrations  of  the  fire-resisting  qualities  of  this  material. 

Load  Tests  and  Factor  of  Safety.  —  In  addition  to  the 
Denver  tests  previously  noted,  many  other  investigations  have 
been  made  concerning  the  strength  of  hollow-tile  arches  of 
various  forms  and  grades  of  material.  Some  of  these  tests, 
particularly  those  of  Mr.  George  Hill  and  Fr.  Von  Emperger,* 

*  See  "Tests  of  Fireproof  Flooring  Material,"  Transactions  Am.  Soc.  C.  E., 
Vol.  XXXIV,  and  "Hollow  Tile  Floors,  Past  and  Present,"  Transactions  Am. 
Soc.  C.  E.,  Vol.  XXXIV. 


596         FIRE    PREVENTION    AND    FIRE    PROTECTION 

have  done  much  to  correct  weaknesses  which  were  inherent  in 
earlier  methods  of  manufacture,  and  to  suggest  further  improve- 
ments which  have  not  been  found  commercially  practicable. 

Generally  speaking,  standard  construction  hollow-tile  arches 
will  safely  carry  the  loads  for  which  they  are  designed,  and  this 
even  after  severe  fire  test.  Witness  the  load  test  made  on  one 
of  the  arches  in  the  Union  Trust  Building  after  the  Baltimore 
fire,  wherein  a  load  of  700  pounds  per  square  foot  was  safely 
carried. 

On  the  other  hand,  fires  have  revealed  skimpings  in  floor-arch 
constructions  which  have  proved  costly  indeed.  Witness  the 
Equitable  Building  in  Baltimore,  and  the  Parker  Building  in 
New  York.  These  experiences  show  that  a  sufficient  margin  or 
factor  of  safety  must  be  allowed  to  care  for  weakened  condition 
due  to  fire  and  water  tests,  —  falling  debris,  —  and  the  impact 
of  falling  loads,  such  as  safes,  etc. 

SELECTION:   CONCLUSIONS 

Selection  of  Hollow-tile  Arches.  —  In  Chapter  XI,  among 
the  requirements  stipulated  for  a  satisfactory  fire-resisting  floor, 
were  ability  to  carry  the  estimated  static  and  moving  loads  with 
a  proper  factor  of  safety,  ability  to  resist  shock  due  to  falling 
debris,  and  ability  to  withstand  a  minimum  damage  by  fire  and 
water. 

From  the  data  previously  given  in  this  and  other  chapters, 
particularly  the  experimental  and  actual  tests  of  different  ma- 
terials, forms  and  conditions,  it  is  possible  to  draw  certain  general 
conclusions  respecting  hollow-tile  arches  for  general  guidance  in 
attaining  the  requirements  enumerated  above. 

Material.  —  Strength  tests  made  on  hollow-tile  arches  show 
that,  for  strength  alone  under  static  loads,  hard-burned  terra- 
cotta is  stronger  than  the  porous  variety.  Impact,  however, 
must  also  be  considered,  and  adequate  tests  show  that  semi- 
porous  terra-cotta  is  much  superior  to  hard  tile  in  resistance  to 
shock.  But  if  a  choice  of  material  seems  difficult  under  these 
conflicting  properties,  a  comparison  of  the  action  of  the  various 
grades  of  terra-cotta  under  fire  and  water  tests  will  show  that 
porous  or  semi-porous  tile  is  usually  far  more  reliable  and  satis- 
factory under  the  combined  conditions  of  load,  shock,  fire  and 
water.  The  conclusion  is,  therefore,  warranted  that: 


TERRA -COTTA    FLOORS,  GIRDER   PROTECTIONS,  ETC        597 

1.  Porous  or  semi-porous  hollow-tile  arches  are  much  to  be 
preferred  to  the  hard-burned  material. 

Form  of  Arch.  —  As  has  been  explained  under  a  previous 
discussion  of  beam  and  girder  protections,  flat  or  unbroken  ceil- 
ings almost  invariably  suffer  less  fire  damage  than  those  paneled 
or  vaulted  constructions  which  require  the  projection  of  beams 
or  girders  below  the  main-ceiling  line.  The  Home  buildings 
(see  page  138)  were  cases  in  point.  The  previously  given  sum- 
mary of  the  condition  of  floor  arches  in  seven  of  the  Baltimore 
buildings  also  shows  that,  in  every  case  where  paneled  ceilings 
were  used,  large  damage  resulted;  while,  conversely,  every  flat- 
ceiling  construction  was  little  damaged.  Hence  it  will  be  found 
that: 

2.  Flat  terra-cotta  arches,  without  projecting  beams  or  girders, 
will  best  resist  fire  damage. 

Construction  of  Arch.  —  As  between  end-,  side-  and  com- 
bination-arches, there  is  no  question  that  those  of  the  former 
type  are  the  strongest  under  both  static  loads  and  impact.  But 
other  considerations,  involving  practical  methods  of  setting  as 
well  as  the  better  protection  of  the  beams  against  both  corrosion 
and  fire  (see  page  565),  make  the  combination  type  of  arch  pref- 
erable for  usual  practice. 

As  the  result  of  his  many  tests  and  experiments  on  terra-cotta 
arches,  Mr.  George  Hill  recommended  that  for  loads  under  150 
pounds  per  square  foot  total,  either  end-  or  side-construction 
arches  be  used;  but  for  loads  exceeding  150  pounds  per  square 
foot  total,  end-construction  arches  should  always  be  used,  with 
the  best  quality  of  mortar.  The  third  conclusion  may,  therefore, 
be  stated  as  follows: 

3.  End-construction   arches  are  stronger  and   more  reliable 
under  heavy  loads  or  severe  shock,  but  combination  arches  more 
nearly  fulfil  all  requirements  of  usual  practice. 

Form  and  Depth  of  Blocks.  —  The  greatest  strength  and 
heat-resistance  will  result  from  a  given  cross-section  of  material 
when  the  blocks  are  made  of  the  simplest  rectangular  form. 

Also,  in  arches  of  the  same  depth  the  strength  varies  directly 
as  the  span.  In  arches  of  the  same  span  the  strength  varies  as 
the  square  of  the  depth.  A  deep  block,  therefore,  makes  a  much 
stronger  floor  than  a  shallower  block  for  the  same  span,  and,  what 
is  equally  important,  a  lighter  and  cheaper  floor.  The  floor  is 
lighter  because  the  additional  depth  to  the  terra-cotta  block  will 


598         FIRE    PREVENTION    AND    FIRE    PROTECTION 

weigh  less  than  the  concrete  leveling  which  would  be  necessary 
over  a  shallower  arch,  and  a  terra-cotta  arch  made  the  full  depth 
of  the  beam  is  cheaper  than  a  smaller  arch  leveled  up  with  con- 
crete. 

But,  aside  from  the  questions  of  cost  and  strength,  fireproofing 
considerations  make  it  desirable  to  employ  a  floor  arch  of  a  depth 
equal  to  the  beam  which  serves  as  its  support.  The  fire  in  the 
Home  Life  Building  showed  the  evil  results  attending  the  prac- 
tice of  permitting  continuous  voids  between  the  tops  of  the  floor 
arches  and  the  under  side  of  the  flooring.  Where  shallow  floor 
arches  are  used,  the  temptation  will  arise  to  save  the  cost  of  the 
concrete  leveling.  Where  the  arches  are  made  the  full  depth 
of  the  beams,  and  concrete  filling  is  laid  between  the  screeds, 
voids  become  impossible. 

From  consideration  of  cost,  strength  and  fire-resistance,  it 
therefore  follows  that: 

4.  The  simplest  form  of  rectangular  blocks  is  preferable,  and 

5.  The  arch  blocks  should  be  of  the  full  depth  of  the  beams, 
plus  2  inches  for  soffit-tile  protection. 

Thickness  of  Material.  —  The  thickness  of  material  is  im- 
portant. The  tendency  of  late  years,  especially  since  the  intro- 
duction of  the  end-construction  type  of  arch,  has  been  to  lighten 
the  thickness  of  the  material.  This  has  been  due  to  the  increased 
load-carrying  capacity  developed  by  the  end-construction  method, 
to  increased  competition,  and  particularly  to  the  desire  to  lessen 
the  freight  charges  for  transportation. 

The  breaking  of  tile  arches  on  the  bottom  is  due  to  the 
inability  of  the  material  to  withstand  inequalities  of  contraction 
and  expansion,  and  it  breaks  in  the  corners,  both  because  the 
strain  is  greatest  and  the  tile  is  weakest  there.  There  is  an  in- 
equality of  expansion  because  it  is  heated  only  on  one  side.  The 
strain  is  greatest  in  the  corners  because  the  expansion  of  one  side 
tends  to  shear  that  side  from  the  adjoining  ones,  and  it  is  weakest 
at  the  corners  because  if  there  is  any  initial  stress  in  the  material 
it  would  more  naturally  occur  there  than  elsewhere,  while  the 
very  fact  that  it  breaks  in  that  particular  place  more  than  any- 
where else  indicates  that  it  is  lacking  in  strength  along  the  edges.* 

When  it  is  remembered  that  the  shrinkage  in  terra-cotta  arch 
blocks  in  the  process  of  drying  and  burning  amounts  to  1J  inches 

*  See  "'Can  Buildings  be  Made  Fireproof,"  by  Corydon  T.  Purdy,  Trans- 
actions American  Societv  of  C;vil  Engineers,  Vol.  XXXIX. 


TERRA-COTTA  FLOORS,  GIRDER  PROTECTIONS,  ETC.   599 

per  foot,  the  initial  stresses  in  the  finished  product  are  easily 
accounted  for. 

The  only  way  of  overcoming  this  weakness  of  hollow  tile  under 
fire  test  is  by  making  the  material  of  a  sufficient  thickness  to 
withstand  these  internal  stresses  and  inequalities  of  expansion, 
and  by  using  well-rounded  corners  or  " fillets",  at  the  junction  of 
all  interior  webs  with  outer  shells,  to  reinforce  the  corners  of 
the  cells.  Hence,  to  secure  a  minimum  breakage  of  the  arch 
soffits, 

6.  Thick  outer  shells  and  interior  webs  are  desirable  in  arck 
blocks,  with  well-rounded  corners  at  all  intersections. 

Skews.  —  The  choice  of  skew  type  has  practically  been  cov- 
ered under  conclusion  3.  It  should  be  borne  in  mind,  however, 
that  side-construction  skews  constitute  the  weakest  portion  of 
a  side-construction  or  combination  arch,  hence,  it  is  important 
to  specify  that 

7.  Side-construction  skews  should  contain  an  interior  sloping 
reinforcing  rib  which  should  start  directly  above  the  flange  of 
the  beam,  and  at  a  point  about  midway  between  the  beam  web 
and  the  edge  of  the  flange  (see  Fig.  207). 

Advantages  and  Disadvantages  of  Hollow-tile  Arches.  — 

Advantages.  —  The  following  points  tend  to  recommend  hollow- 
tile  floor  arches: 

Flush  or  unbroken  ceilings,  except  at  especially  deep  girders. 

Suspended  ceilings  not  necessary,  except  for  segmental  forms. 

Arches  are  usually  full  depth  of  beams,  thus  contributing 
strength  and  rigidity. 

The  setting  is  more  independent  of  weather  conditions  than 
where  concrete  is  used. 

No  dripping  of  water  occurs  during  the  setting. 

Less  delay  and  interference  to  other  work  than  with  concrete. 

Disadvantages.  —  A  great  disadvantage  lies  in  the  difficulty 
of  adapting  hollow  tile  to  the  filling  of  irregular-shaped  spaces. 
Hollow-tile  floor  arches  may  be  used  most  satisfactorily  where 
the  arrangement  of  the  beams  and  girders  is  rectangular;  but 
in  many  cases  such  rectangular  arrangement  is  impossible,  due 
to  the  outline  of  the  building  site.  The  conditions  of  floor  fram- 
ing often  cause  other  irregularities,  such  as  radiating  girders, 
and  other  distortions  around  elevator  wells,  light  shafts,  etc. 
Under  such  conditions  the  irregular  panels  become  largely  a 
matter  of  patchwork,  without  systematic  arrangement  of  the 


600         FIRE    PREVENTION    AND    FIRE    PROTECTION 

blocks,  due  to  the  incapacity  of  the  rectangular  blocks  to  adapt 
themselves  to  other  than  rectangular  forms.  The  usual  result 
is  a  filling  of  tile  and  parts  of  tile  wedged  together  in  the  most 
convenient  manner,  with  a  plentiful  supply  of  mortar  to  fill  the 
interstices. 


CHAPTER  XVIII. 
CONCRETE  FLOORS  AND  REINFORCED  CONCRETE. 

THE  wonderful  development  of  concrete  construction  in  the 
United  States  during  the  past  decade  is  an  index  of  its  value  as 
a  constructive  material.  Office  buildings,  factories,  schools, 
theaters,  residences  and  farm  buildings  —  in  fact  all  classes  of 
structures  —  are  now  frequently  built  either  entirely  or  in  part 
of  concrete. 

As  used  in  the  superstructure  of  buildings,  concrete  is  employed 
in  the  construction  of  floors,  roofs,  columns,  walls  and  partitions; 
but  floors,  for  which  it  has  been  most  extensively  employed,  will 
alone  be  considered  in  this  chapter. 

General  Types  of  Concrete  Construction.  —  The  special 
applicability  of  concrete  construction  to  floors  and  roofs  has  been 
made  possible  by  the  gradual  development  of  approved  practice, 
in  which  varied  forms  of  metal  reinforcement  have  been  intro- 
duced within  the  constructions  in  order  to  add  tensile  strength 
to  the  system,  while  reducing  the  thickness  and  hence  the  weight. 
The  present  tendency  in  the  use  of  concrete  floors  is  away  from 
special  or  patented  systems  and  toward  more  general  applica- 
tions of  the  principles  of  reinforced  concrete;  but  two  broad 
types  of  floor-  and  roof-constructions  result  from  the  treatment 
of  columns  and  girders,  viz.,  those  types  depending  for  support 
upon  steel  columns,  girders  and  floor  beams,  or  steel-frame  and 
concrete  construction,  —  and  those  types  in  which  the  entire  con- 
struction is  of  concrete,  usually  'termed  reinforced  concrete  in 
contradistinction  to  the  former  type.  But,  whichever  type  is 
employed,  the  construction  should  be  designed,  and  preferably 
superintended,  by  a  capable  engineer  experienced  in  concrete 
work,  and  not  by  a  concrete  construction  company.  There  are 
both  honest  and  reliable  concrete  construction  companies  who 
will  design  concrete  work  in  the  hope  of  securing  the  contract 
for  same,  but,  generally  speaking,  this  is  conducive  to  neither  the 
best  nor  the  cheapest  results. 

601 


602         FIRE    PREVENTION    AND    FIRE    PROTECTION 

General  Principles  of  Floor  Design.  —  The  effect  oi  a  super- 
imposed load  upon  a  beam  or  slab,  of  whatever  material,  is  to 
produce  tension  in  the  lower  portion  of  the  beam  or  slab,  and 
compression  in  the  upper  portion.  Plain  concrete,  i.e.,  without 
metal  reinforcement,  is  strong  in  compression  but  comparatively 
weak  in  tension.  A  concrete  beam  12  inches  deep,  8  inches  wide, 
and  12  feet  between  supports  will  carry  a  center  load  of  about 
2500  pounds  before  failure.  If,  however,  reinforcing  steel  bars 
are  placed  in  the  lower  portion  of  the  above  beam,  the  super- 
imposed center  load  may  be  increased  to  about  30,000  pounds 
before  failure  occurs.  This  great  difference  in  load-carrying 
capacity  is  due  solely  to  the  introduction  of  the  steel  reinforce- 
ment to  increase  the  tensile  strength  of  the  concrete  in  the  lower 
portion  of  the  beam.  The  method  of  computing  the  necessary 
amounts  of  concrete  and  steel  to  provide  safely  for  the  compres- 
sion and  tension,  respectively  induced  by  the  required  load,  is 
the  essence  of  reinforced  concrete  design.  Ordinary  practice 
assumes  that  the  compression  in  the  upper  portion  of  beam  is 
wholly  taken  up  by  the  concrete,  and  that  the  tension  in  lower 
portion  of  beam  is  wholly  cared  for  by  the  metal  reinforcement. 
If  the  area  of  this  metal  reinforcement  is  too  small,  weakness  will 
be  apparent  as  soon  as  the  elastic  limit  of  the  metal  has  been 
reached,  while  if  the  area  is  too  large,  weakness  or  failure  will 
occur  by  the  crushing  of  the  concrete  in  the  upper  portion. 

In  pure  reinforced  concrete  design,  somewhat  more  complex 
problems  are  involved  in  the  shear  requirements  in  girders,  in 
the  proportionment  of  columns,  and  in  the  attachment  of  gird- 
ers to  columns;  hence  for  complete  information  regarding  the 
theory  and  practice  of  proportioning  reinforced  concrete,  refer- 
ence should  be  made  to  some  authoritative  text-book,  such  as 
Taylor  and  Thompson's  "  Treatise  on  Concrete,  Plain  and  Rein- 
forced," or  C.  F.  Marsh's  "  Reinforced  Concrete."  Attention 
will  here  be  confined  to  a  few  fundamental  principles  governing 
good  design,  with  especial  reference  to  fire-resistance. 

Thickness  and  Weights  of  Floor  Slabs.  —  Manifestly,  a 
minimum  of  slab  material  is  required  by  bays  or  panels  containing 
supporting  beams  placed  comparatively  close  together,  but  a 
limiting  thickness  of  slab  may  easily  be  reached  by  practical 
considerations  other  than  mere  economy  in  the  quantity  of  con- 
crete. Thus,  if  steel  beams  are  used,  steel  is  proportionately 
more  expensive  than  concrete;  very  thin  slabs  are  more  expen- 


CONCRETE    FLOORS   AND    REINFORCED    CONCRETE       603 


sive  to  construct  than  thicker  ones;  difficulty  arises  in  the  prac- 
tical placing  of  reinforcement  in  thin  slabs,  and  sufficient  concrete 
must  be  left  at  the  soffit  for  the  adequate  protection  of  the  rein- 
forcement. These  conditions  generally  limit  the  economical 
thinness  of  slabs  to  3  inches,  and  this  minimum  should  only  be 
employed  where  excessive  live-  or  concentrated-loads,  or  shock, 
are  absent. 

For  ordinary  loads,  the  thickness  of  concrete  slab  (not  includ- 
ing cinder  fill)  should  be  at  least  five-eighths  of  an  inch  per  foot 
of  span,  with  a  preferable  minimum  thickness  of  3^  inches.  The 
following  table*  gives  the  weight  of  reinforced  concrete  slabs  per 
square  foot,  based  on  average  weights  of  150  pounds  per  cubic 
foot  for  broken  stone-  or  gravel-concrete,  and  112  pounds  per 
cubic  foot  for  cinder  concrete,  to  which  are  added  4  pounds  per 
cubic  foot  to  cover  the  maximum  weight  of  about  1  per  cent,  of 
reinforcing  steel: 

WEIGHT  OF  REINFORCED  CONCRETE  SLABS  PER  SQUARE  FOOT. 


Thickness 
in  inches. 

Cinder  con- 
crete, Ibs. 

Stone  con- 
crete, Ibs. 

Thickness 
in  inches. 

Cinder  con- 
crete, Ibs. 

Stone  concrete, 
Ibs. 

2 

19 

26 

5i 

53 

70 

2J 

24 

32 

6 

58 

77 

3 

29 

38 

7 

68 

90 

3i 

34 

45 

8 

77 

103 

4 

39 

51 

9 

87 

115 

4i 

43 

58 

10 

97 

128 

5 

48 

64 

Position  of  Reinforcement.  —  As  the  greatest  tension  in  a 
beam  or  slab  exists  at  the  under  surface,  the  metal  reinforcement, 
to  be  of  the  greatest  service,  should  be  as  near  the  bottom  as 
possible;  but  the  protection  of  the  metal  against  corrosion  or 
possible  heat  or  fire  requires  that  a  sufficient  thickness  of  concrete 
be  left  at  the  ceiling  line,  below  the  metal,  to  provide  such  pro- 
tection. Reference  to  Chapter  VII  (page  249)  will  show  that 
this  protective  layer  of  concrete  should  never  be  less  than  1  inch 
for  short-span  floor  slabs,  nor  less  than  1£  inches  for  long-span 
floors,  girders  and  beams,  nor/  less  than  2  inches  for  especially 
heavy  or  important  members. 

*  Taylor  and  Thompson. 


604         FIRE    PREVENTION    AND    FIRE    PROTECTION 

The  exact  position  of  the  reinforcement  in  the  concrete,  there- 
fore, becomes  of  great  importance,  as  this  factor  not  only  serves 
to  affect  the  strength,  but  the  fire-safety  of  the  construction  as 
well. 

Forms  of  Reinforcement.  —  To  prevent  the  cracking  of 
concrete,  due  to  the  stretching  or  slipping  of  the  reinforcement, 
the  form  of  steel  should  be  such  as  to  provide  the  greatest  possible 
adhesion  to  the  surrounding  concrete. 

The  usual  forms  are:  deformed  rods  or  bars,  which  may  be 
twisted,  grooved  across  the  sides,  or  deformed  in  some  manner  so 
as  to  increase  the  mechanical  bond  between  the  section  and  the 
surrounding  concrete,  —  expanded  metal,  —  or  some  form  of 
wire  fabric. 

Where  rods  or  bars  are  employed,  many  small  ones  are  pref- 
erable to  few  large  ones,  as  the  area  of  adhesion  or  mechanical 
bond  is  thereby  increased.  But  this  principle  may  be  carried 
to  extremes,  as  when  small  rods  are  replaced  by  a  still  greater 
number  of  wires  in  light-metal  fabrics,  in  which  case  there  is 
greater  danger  of  failure  by  corrosion. 

If  plain  rods  are  used,  they  must  be  prevented  from  slipping 
by  selecting  very  long  lengths,  or  by  anchoring  the  ends,  or  both. 
If  the  ends  are  bent  for  this  purpose,  there  must  be  a  considerable 
thickness  of  concrete  beyond  the  bend  to  prevent  the  tendency 
under  load  to  straighten  out  and  thrust  through  the  concrete.* 

The  best  slab  reinforcement  for  ordinary  spans  consists  of 
i-inch  to  f-inch  round  or  square  rods  or  bars  of  some  deformed 
shape,  or  of  3-inch-mesh  expanded  metal  of  not  less  than  No.  10 
gauge,  the  area  of  rnetal  to  be  as  required  by  span  and  load. 

Composition  of  Concrete.  —  As  regards  fire-resistance,  it 
has  been  stated  in  Chapter  VII  that  the  aggregate  largely  deter- 
mines the  result.  Conclusive  data  on  this  point  are  given  under 
a  later  discussion  of  fire  tests  of  concrete  floors  (see  page  613,  etc.). 

In  steel-frame  and  concrete  construction,  cinder  concrete  of  a 
proportion  of  1  cement,  2  of  sand  and  5  or  6  of  cinders,  has  been 
widely  used  for  slab  or  arch  forms  where  the  beams  are  spaced 
not  over  8  foot  centers.  Cinders  generally  make  the  cheapest 
possible  aggregate  and  the  lightest  possible  construction.  They 
are  highly  satisfactory  as  regards  fire-resistance,  —  problematical 
as  regards  corrosive  tendencies,  —  and  unsuited  to  work  requir- 
ing considerable  strength  (see  also  Chapter  VII,  page  250). 
*  Taylor  and  Thompson. 


CONCRETE   FLOORS   AND    REINFORCED    CONCRETE      605 

Stone-  or  gravel-concrete  is  the  recognized  standard  in  present- 
day  practice.  The  growing  difficulty  of  obtaining  a  grade  of 
cinders  satisfactory  for  even  the  lightest  and  cheapest  work  has 
resulted  in  the  almost  universal  use  of  concrete  made  of  gravel 
or  crushed  stone  for  both  steel-frame  arid  concrete  floors  and  for 
all-concrete  structures.  In  the  latter  type,  cinder  concrete  is  not 
suited  for  use  in  either  beams,  girders  or  columns. 

Stone  concrete  is  usually  mixed  in  the  proportion  of  1  part 
cement,  2  or  2J  parts  sand  and  4  or  5  parts  screened  stone  or 
gravel.  If  a  wide  margin  of  safety  is  used,  a  1  :  3  :  6  proportion 
may  be  amply  strong,  whereas  if  an  extra  margin  of  strength  is 
desired,  a  1  :  2  :  4  mixture  may  be  employed  (see  also  "  Aggre- 
gates," page  623). 

Regarding  concrete  "fill,"  see  Chapter  XI,  page  339. 

Steel-frame  and  Concrete  Floors.  —  The  position  of  the 
concrete  slab  in  reference  to  the  supporting  beams  determines 
the  appearance  of  the  soffit  or  ceiling,  viz: 

(1)  Paneled  construction,  wherein  the  floor  is  not  uniformly  as 
deep  as  the  supporting  beams,  and 

(2)  Flush  construction,  wherein  the  floor  is  uniformly  of  the 
full  depth  of  the  beams. 

Form  (2)  may  be  made  of  form  (1)  as  far  as  appearance  is 
concerned  by  introducing  a  suspended  ceiling,  as  described  in  a 
later  paragraph. 

Paneled  Ceiling  Construction.  —  In  this  form  the  slabs  are 
usually  placed  high  enough  to  permit  the  floor  sleepers  or  screeds 
to  pass  over  the  beams.  Various  types  of  reinforcement  are 
employed  in  various  ways,  as  shown  in  the  following  typical 
illustrations.  Rods  or  flat  bars  may  be  used  perfectly  level,  or 
sagged  down  at  center  of  span.  They  may  either  pass  directly 
over  the  beams,  be  hooked  over  the  beam  flanges,  or  be  suspended 
from  the  upper  flanges  by  means  of  saddles  or  hangers. 

Expanded  metal  or  wire  fabric,  etc.,  may  be  simply  laid  level 
in  the  slab,  or  passed  over  the  beams  and  sagged  at  center.  But 
whatever  the  form  of  slab,  provision  should  always  be  made  for 
the  protection  of  the  beams,  especially  of  the  lower  flanges,  as 
shown  in  the  following  illustrations  and  as  described  in  a  later 
paragraph. 

Fig.  235  illustrates  the  typical  floor  construction  in  the  United 
States  Post  Office  and  Custom  House  at  Richmond,  Va.  The 
floor  beams  are  generally  12-inch  and  15-inch  I-beams,  of  17-  to 


606 


FIRE    PREVENTION    AND    FIRE    PROTECTION 


20-foot  spans,  spaced  6  feet  6  inches  to  7  feet  centers.     The 
floor  slabs  are  3J-inch  stone  concrete,  the  expanded  metal  rein- 


c  3  Beveled  Sleepers, 


[etal  Reinforcement 
10  Wire,Loops,  6'6ts. 


FIG.  235.  —  Paneled  Floor  Construction,  Reconstruction  of  U.  S.  P.  O.  and 
Custom  House,  Richmond,  Va. 

for  cement  passing  over  the  beams.  The  lower  flanges  of  beams 
are  protected  by  2  inches  of  concrete,  while  wire  loops,  made  of 
No.  10  wire,  are  passed  around  the  beams  at  intervals  of  6  inches 
to  aid  in  holding  the  concrete  in  place. 

The  carrying  of  the  haunches  of  the  slab  down  to  the  lower 
flanges  of  the  I-beams  not  only  forms  the  best  means  of  pro- 
tecting the  beams  but  increases  the  strength  of  the  slab  as  well. 

Fig.  236  shows  a  similar  floor  in  the  United  States  Court  House 
and  Post  Office  at  Los  Angeles,  Cal.,  in  which  the  metal  reinforce- 


XTerrazzo  or  Wood  Flooring- 


Bevelled  Wood  Sleepers 


V  3}4' stone  or  gravel  concrete 
%'g-alv.  wire,  9'c.c 
No.24:  metal  lath 


- - —  J.TI  u.4,t  u  

This  construction  for  12  I's  and  over  This  construction  for  10'i's 

and  under 

FIG.  236.  —  Paneled  Floor  Construction,  U.  S.  Court  House  &  P.  O.,  Los 
Angeles,  Cal. 

ment  was  laid  flat.  This  reinforcement^  was  specified  to  be  No.  10 
expanded  metal,  3-inch  mesh,  or  galvanized -wire  fabric,  made  of 
No.  8  and  No.  10  wires  in  4-inch  by  6-inch  mesh,  with  approved 
type  of  lock-woven  or  electrically-welded  intersections,  the  No.  8 
wires  to  be  laid  4  inches  centers  at  right  angles  to  the  supporting 


CONCRETE   FLOORS   AND    REINFORCED    CONCRETE       607 


U.  S.  Court  House  &  P.  O.,  Spokane, 
Wash. 


beams.  Beams  12  inches  deep  and  over  are  wrapped  with  No.  24 
metal  lath  around  the  lower  flanges,  and  then  with  loops  of  iV 
inch  galvanized  wire,  9  inches  centers.  For  beams  10  inches 
deep  and  under  the  wrapping 
was  the  same,  except  that  the 
loops,  as  well  as  the  metal 
lath,  surrounded  the  lower 
flanges  only. 

Fig.  237  illustrates  the  floor 
construction,  where  flat  ceil- 
ings were  not  required,  in  the 
United  States  Post  Office,  Court 
House  and  Custom  House  at 
Spokane,  Wash,  (the  flat-ceil- 
ing construction  is  shown  in 

Fig.  244).      The  girders  are  15-    FlG-  237.  — Paneled  Floor  Construction, 

inch,  18-inch  and   24-inch  I's, 

and   the  beams  are   generally 

10-inch  25-pound  and  12-inch  31J-pound  I's,  5  feet  to  5  feet  9 

inches,  etc.     The  floor  slabs  are  of  stone  concrete,  4  inches  thick. 

This  construction  is  particularly  interesting  in  that  the  wire 
loops  used  to  hold  the  concrete  around  the  girders  and  beams 
are  also  used  to  support  the  centering,  and  the  suspended  ceiling 
where  used  (compare  Fig.  244).  To  hold  the  wood  centering, 
double  loops  of  No.  10  wire,  12  inches  centers,  are  passed  over 
the  beams,  the  ends  hanging  down  well  below  the  soffit  line.  The 
ledger  boards  of  the  centering  are  then  supported  by  twisting 
together  the  loose  ends  of  the  loops,  thus  forming  double  wire 
hangers  for  each  ledger  board.  It  was  required  that  the  concrete 
underneath  all  flanges  of  I-beams  or  channels  be  placed  fairly 
wet,  and  worked  thoroughly  under  from  one  side  of  form  only, 
or  until  tp  be  seen  well  filled  from  the  other  side.  After  the 
removal  of  centering,  the  wires  are  snipped  off  at  the  soffit  line. 

Flush  Ceiling  Construction.  —  This  form  is  best  adapted 
to  light  floor  loads,  as  in  hotels,  apartment  houses,  etc.,  as  it  is 
only  possible  with  any  degree  of  economy  when  shallow  beams 
of  moderate  spans  can  be  employed.  Deep  beams  require  too 
much  "fill,"  thus  adding  greatly  to  the  weight.  The  slab  should 
always  be  placed  low  enough  on  the  beams  to  leave  one  inch  of 
concrete,  and  preferably  two  inches,  between  the  lower  flanges 
of  beams  and  the  ceiling  line.  As  before,  various  forms  of  rein- 


608         FIRE   PREVENTION   AND   FIRE   PROTECTION 

forcement  are  used,  generally  resting  on  the  lower  flanges  of 
beams. 

A  typical  floor  of  this  form  is  shown  in  Fig.  238. 

^-Finished  Floor 
^  _          /    /-  Rough  Floor 

'  .  u 


fe^S-v^A^ 


Reinforcement ' 
FIG.  238.  —  Flush  Ceiling  Concrete  Slab  Construction. 

It  should  be  noted  that  any  flush  ceiling  construction,  whether 
of  type  similar  to  the  above,  or  of  the  " mushroom"  or  " paneled 
slab"  types  as  described  later,  will  obviate  the  fire  damage  which 
usually  results  from  the  employment  of  projecting  girders,  and 
will  permit  maximum  throw  to  both  inside  sprinkler  heads  and 
hose  streams  from  without. 

Lintel  Construction*,  wherein  a  monolithic  slab  as  described 
above  is  replaced  by  a  series  of  lintels  or  beams  of  reinforced 
concrete,  has  been  used  in  some  instances.  Such  lintels  rest  on 
the  lower  flanges  of  the  steel  beams,  being  made  at  the  factory, 
of  suitable  depth  and  span  to  suit  the  various  bays.  They  are 
usually  of  I-section,  reinforced  by  rods  or  metal  fabric,  and  are 
either  placed  contiguous,  in  which  case  no  centering  is  required 
except  for  the  beam  protections,  or  spaced  somewhat  apart, 
as  in  the  "Waite"  method,  the  space  between  the  lower  flanges 
being  filled  with  cinder  concrete.  The  great  possibilities  in- 
herent in  this  construction,  both  as  regards  load-carrying 
capacity  and  fire-resistance,  are  indicated  by  the  fire  and  load 
tests  made  by  the  British  Fire  Prevention  Committee  on  the 
lintel  construction  known  as  the  "Armocrete"  Tubular  System 
(see  page  617). 

Beam  and  Girder  Protections.  —  The  importance  of  the 
adequate  protection  of  beam  soffits  and  girders  has  already  been 
pointed  out  in  Chapter  XI,  while  in  Chapter  XVII  numerous 
examples  of  such  protections  have  been  given  in  connection  with 
hollow-tile  floor  arches. 

Where  concrete  floor  systems  are  used,  the  protection  of  beams 
and  shallow  girders  is  a  comparatively  simple  matter,  as  the  en- 

*  Compare  with  "Unit"  or  "Separately-moulded"  System,  page  613. 


CONCRETE   FLOORS   AND    REINFORCED    CONCRETE      609 


casing  concrete  is  poured  at  the  same  time  as  the  floor  slab  or 
arch,  thus  making  a  monolithic  construction  without  the  joints 
which  are  apt  to  prove  so  vulnerable  in  the  case  of  hollow  tile. 
The  principal  difficulty  is  encountered  in  placing  the  concrete 
under  the  lower  flanges  of  beams,  especially  where  only  about 
one  inch  of  concrete  is  allowed  for.  But  if  a  protection  under 
the  beams  of  not  less  than  2  inches  is  called  for,  and  if  the  ma- 
terial is  used  fairly  wet  and  is  worked  through  the  form  from  one 
side  only,  there  should  be  no  difficulty  in  producing  satisfactory 
results,  especially  if  metal  reinforcement  is  provided  for  both 
soffits  and  sides  of  beams,  as  shown  in  Figs.  235  and  236. 

Even  with  concrete  floor  slabs,  terra-cotta  beam  casings  are 
sometimes  used.     Fig.  239  illustrates  a  porous  terra-cotta  beam 


Floor  Line 


Porous- 
T.C.  blocks^ 


10  Wire  loops 
~at  each  joint) 


FIG.  239.  —  Concrete  Floor  Slabs  with  Terra-cotta  Beam  Casing,  U.  S.  Assay 
Office,  N.  Y. 

casing  as  used  in  the  United  States  Assay  Office,  N.  Y.     Loops 
of  No.  10  wire  are  embedded  in  each  joint. 


/I  Cement  Fi 
/Conor 


I  Cement  Finish 

/Concrete  Filling 

-Stone Concrete  Slab  \ 


-.Finish  ail  T.C. 
with  cement  plaster 


FIG.  240.  —  Concrete  Floor  Slabs  with  Terra-cotta  Girder  Casing,  U.  S.  Assay 
Office,  N.  Y. 


610 


FIRE    PREVENTION    AND   FIRE    PROTECTION 


For  deep  I-beam  girders,  or  for  plate  or  box  girders,  hollow- 
tile  blocks  must  usually  be  resorted  to  either  in  whole  or  in  part. 
Fig.  240  shows  the  casing  of  a  24-inch  I-beam  girder,  also  in  the 

,  I     /2r'x  3'Nailing; Strips 


I      Fin.  Floors 


i/ 

!  //'Additional  Reinforcement 

Ll^^i^,^^,;^^  -*--- 


Stone  Concrete 
Metal  Reinforcement 
Terra  Cotta 


Fia.  241.  —  I-Beam  Girder  Protection,  Proposed  Appraisers'  Stores,  Boston. 

United  States  Assay  Office,  N.  Y.,  while  Figs.  241,  242  and  243 
show  respectively  the  protections  designed  for  an  I-beam  girder, 


Metal  Reinforcement 
Terra  Cotta 

Sheet  Metal  Clips., 
/one  each  Soffit  block 


FIG.    242.  —  Plate-girder    Protection,    Proposed    Appraisers'    Stores,    Boston. 


a  plate  girder  and  a  box  girder,  in  the  proposed  United  States 
Appraisers'  Stores,  Boston,  Mass. 


CONCRETE   FLOORS  AND   REINFORCED   CONCRETE      611 

/-2nd  Floor 


-2x%jFlats20c't'rs. 
,ods 


-*J2t*-/  VMetal  reinforcement 

'Slab  may  be  molded  and  set, 
or  cast  in  place 
FIG.  243.  —  Box-girder  Protection,  Proposed  Appraisers'  Stores,  Boston. 

Suspended  Ceilings.  —  As  regards  the  general  efficiency  of 
suspended  ceilings,  see  Chapter  XI,  page  343. 

The  flat  ceiling  construction  used  in  the  United  States  Post 
Office,  Court  House  and  Custom  House  at  Spokane,  Wash.,  in 

Floor  Line 


FIG.  244.  —  Furred  Ceiling  Construction,  U.  S.  P.  O.  Bldg.,  Spokane,  Wash. 

connection  with  concrete  floors,  is  shown  in  Fig.  244.     Tees, 
1-inch  by  1-inch,  12  inches  centers,  covered  with  metal  lath,  are 


612 


FIRE    PREVENTION    AND    FIRE    PROTECTION 


suspended  by  means  of  double  No.  10  galvanized-wire  loops, 
12  inches  centers,  at  the  beams  and  at  wall  channels.  At  the 
deeper  girders,  wire  hangers  are  used,  as  shown.  Where  the  tees 
run  at  right  angles  to  the  girder,  the  wire  hangers  are  spaced  by 
means  of  a  J-inch  diameter  rod,  running  the  full  length  of  girder, 
just  above  the  tees. 

Fig.  245  illustrates  the  suspended-ceiling  construction  as  em- 
ployed in  connection  with  the  floors  shown  in  Fig.  235. 


10  Wireloops  6'ctr's.t" 
Alternate  loops  doubled 
and  used  to 
support  furring 


'Metal  Furring  1  Ts  or  Ls_^  21«-  vFin.  Ceiling 
FIG.  245.  —  Furred  Ceiling  Construction,  U.  S.  P.  O.  Bldg.,  Richmond,  Va. 

Floors  in  Reinforced  Concrete  Buildings  embody  the  same 
principles,  and  often  the  same  forms,  as  previously  described, 
except  that  reinforced  concrete  beams  and  girders  are  substi- 
tuted for  the  steel  beams  and  girders.  Among  the  more  noted 
special  types  of  construction  may  be  mentioned  the  "  Mush- 
room" System,  the  paneled-slab  construction,  and  the  "Unit" 
or  separately-moulded  system. 

The  "Mushroom"  System  was  invented  and  patented  by 
Mr.  C.  A.  P.  Turner  of  Minneapolis,  Minn.  In  this  system, 
continuous  floor  slabs  of  a  uniform  thickness  are  supported  by 
the  walls  and  columns,  without  the  use  of  projecting  beams  or 
girders.  A  flat  centering  over  the  entire  area  is,  therefore,  used. 
The  system  derives  its  name  from  the  manner  in  which  the 
columns  are  flared  out  at  the  top  by  means  of  reinforcing  bars 
which  are  placed  both  radially  and  circumferentially,  thus  re- 
sembling a  mushroom  shape.  The  slabs  are  reinforced  by  rods 
running  diagonally  across  the  slab  from  column  to  column  in  two 
directions,  and  also  by  rods  of  the  same  size  running  from  column 
to  column  along  the  outer  lines  of  each  floor  panel. 

Paneled- slab  Construction  *  consists  of  paneled  slabs,  sup- 
ported upon  flaring  column  heads.  The  ordinary  projecting 
*  For  more  complete  description,  see  Engineering  News,  January  27,  1910. 


CONCRETE   FLOORS   AND    REINFORCED    CONCRETE       613 

girders  running  from  column  to  column  are  replaced  by  very 
wide  but  shallow  girders,  running  in  both  directions,  between 
flared  column  heads  or  capitals.  Thus  each  bay  between  col- 
umns becomes  one  large  slightly  recessed  panel. 

The  "Unit"  or  "Separately-moulded"  System,*  in  con- 
tradistinction to  monolithic  construction,  consists,  as  the  appella- 
tions indicate,  of  various  reinforced  concrete  members,  such  as 
columns,  girders,  and  either  lintels  or  slabs  for  floor  panels,  all 
of  which  are  moulded  either  at  a  factory  and  shipped  to  the  site, 
or  preferably,  on  the  ground.  The  reinforcing  bars  in  the  mem- 
bers are  left  projecting  at  the  connections,  so  that,  after  the 
erection  of  the  units  by  means  of  cranes  or  derricks,  they  may  be 
embedded  in  a  jointing  pouring  of  concrete,  usually  from  2  to 
3  per  cent,  of  the  total,  so^as  to  give  practically  a  continuous 
construction. 

The  only  reason  for  being  of  the  separately-moulded  concrete 
building  is  economy.  There  can  be  no  claim  that  under  equal 
conditions  of  manufacture  it  is  stronger,  more  roomy  or  better 
looking  than  its  monolithic  predecessor;  in  these  respects  its 
highest  expectation  can  be  but  equality.  In  the  matter  of  cost, 
however,  it  has  theoretically  the  better  of  the  argument  because 
of  the  reduction  in  the  use  of  expensive  forms,  a  reduction  that 
has  been  the  aim  of  all  concrete  users  for  ten  years  past.  Forms 
flat  on  the  ground  on  a  mixing  board  may  be  of  much  lighter 
material,  less  complicated  design,  and  much  more  easily  trans- 
ferred for  new  units  than  when  erected  in  the  building  —  obvi- 
ously the  total  cost  for  them  must  be  less.  So,  too,  the  labor 
for  erecting  them  and  for  filling  them  with  concrete  must  show  a 
considerable  reduction.* 

FIRE  AND  LOAD  TESTS  OF  CONCRETE  FLOORS 

New  York  Building  Department  Tests.  —  With  the  excep- 
tion of  the  Expanded  Metal  Company's  floor,  practically  all  of 
the  types,of  concrete  floors  covered  in  the  original  tests  of  1896 
and  1897  were  of  " systems"  or  patented  constructions  which 
are  now  obsolete.  Later  tests  of  more  general  forms  have  been 
made  in  conjunction  with  the  Building  Department,  usually  by 
Professor  Woolson,  among  which  may  be  mentioned  the 

Test  of  "Kahn"  System  by  Columbia  Fire-testing  Sta- 
tion, f  —  The  conditions  of  test  were  those  prescribed  by  the 
New  York  Building  Department  (see  Chapter  V,  page  123). 

*  For  descriptions  of  several  buildings  erected  under  this  method,  see 
Engineering  News,  June  15,  1911. 

t  See  "Columbia  Fire  Station  Tests,"  No.  5,  1904. 


614  FIRE    PREVENTION    AND    FIRE    PROTECTION 

The  floor  tested  constituted  the  roof  of  the  building,  and 
was  carried  on  two  reinforced-concrete  girders  of  the  same  system 
as  the  floor.  These  girders  were  18  inches  deep  including  the 
floor  of  which  they  formed  a  part.  They  were  spaced  15  feet  on 
centers  and  had  a  clear  span  of  14  feet  between  the  walls.  The 
actual  clear  span  of  the  floor  slab  between  the  girders  was  13  feet 
8  inches. 

The  reinforcing  metal  in  both  floor  and  girders  was-  the 
Kahn  bar  with  its  wing  projections.  The  bars  in  the  floor  were 
^  inch  square.  One  set  spaced  8  inches  on  centers  running  from 
girder  to  girder,  and  another  similar  set  was  run  at  right  angles 
to  the  first  but  spaced  2  feet  apart.  One-inch  bars  were  used  in 
the  girders. 

The  concrete  for  the  floor  was  mixed  in  proportion  of  1 
cement,  2f  sand  and  5  broken  stone,  and  1,  2,  4  for  the  girders; 
"Vulcanite"  Portland  cement  was  used,  and  the  stone  was  trap 
rock  crushed  to  J-inch  size.  ... 

Ceiling  was  not  plastered. 

During  the  test  several  cracks  developed  on  the  roof  run- 
ning in  various  directions,  as  the  floor  sagged  from  expansion 
due  to  the  heat..  .  .  .  No  cracks  were  visible  on  the  under  side, 
and  later,  when  the  roof  was  flooded,  no  leaking  of  water  through 
the  cracks  was  noticeable. 

The  ceiling  was  in  excellent  condition.  The  concrete  was 
somewhat  pitted  where  subjected  to  the  force  of  the  water,  but 
no  flaking  had  occurred  and  no  cracks  were  apparent  except  a 
horizontal  crack  about  3  feet  long  in  the  side  of  the  south  girder, 
and  a  few  very  small  cracks  in  the  bottom  of  each  girder. 

No  exposure  of  the  reinforcing  metal  was  made  except  a 
few  small  holes  each  about  i  inch  in  area.  Practically  the  metal 
protection  in  floor  and  girders  was  complete. 

There  was  a  deflection  of  4J  inches  in  the  middle  of  the  floor 
span  during  the  fire;  this  included  a  deflection  of  If  inches  in  the 
middle  of  the  girders.  When  the  load  was  removed  and  the  floor 
allowed  to  cool  the  deflection  was  reduced  to  If  inches  for  the 
floor,  and  -ft  mcn  an(l  f  mc^  respectively  for  the  girders.  The 
final  loading  to  600  pounds  per  square  foot  produced  a  total 
deflection  in  the  middle  of  the  girders  of  }f  inch  and  1£  inches 
respectively.  The  deflection  of  the  floor  slab  relative  to  the 
girders  when  under  full  load  was  2 g\  inches. 

The  full  load  was  left  on  the  floor  16  hours  with  practically 
no  increase  in  deflection.  After  the  load  was  discharged  a  re- 
covery of  about  an  inch  was  noted,  though  it  was  not  accurately 
measured. 

Tests  of  the  British  Fire  Prevention  Committee  comprise 
the  most  systematic  if  not  the  most  extensive  fire  and  water 
tests  of  concrete  floor  constructions  yet  undertaken.  Journal 
No.  VI  of  the  Committee,  1911,  gives  tabulated  summaries  of 
fifteen  floor  constructions  which  have  been  tested  under  the  con- 


CONCRETE   FLOORS   AND    REINFORCED    CONCRETE       615 

ditions  necessary  for  classification  under  "Full  Protection,"  of 
which  one  was  the  "New  York"  reinforced  terra-cotta  arch, 
described  in  Chapter  XVII;  one  was  a  "combination"  terra- 
cotta and  concrete  floor,  as  described  in  Chapter  XIX;  one 
was  of  reinforced  brick  and  concrete;  while  12  were  of  various 
forms  of  concrete  construction,  some  with  supporting  steel  beams, 
some  with  reinforced  concrete  girders,  and  others  of  the  lintel 
construction.  These  tests  are  described  in  detail  in  "Red 
Books"  Nos.  23,  34,  61,  64,  96,  101,  103,  106,  107,  108,  109,  112, 
114,  118,  119  and  125,  to  which  reference  should  be  made  for 
detailed  information.  Those  of  particular  value  in  determining 
the  fire-resistance  of  concrete  floors  may  be  briefly  extracted  as 
follows : 

Steel-beam  and  Concrete  Floors.  —  "Red  Book"  No.  101  describes 
tests  made  (1905)  to  observe  the  effects  of  fire  and  water  upon 
concretes  composed  of  various  aggregates.  The  tests  included 
seven  bays  of  equal  span  and  thickness,  the  quantity  and  quality 
of  the  Portland  cement  being  identical  in  each  case,  but  with 
different  aggregates  as  follows: 

Bay  No.  1.  —  Blast-furnace  slag,  —  3:2:1. 

Bay  No.  II.  —  Broken  brick,  —3:2:1. 

Bay  No.  III.  —  Broken  granite,  —3:2:1. 

Bay  No.  IV.  —  Burnt  ballast,  or  clay  burned  with  slack  coal,  — 
5  :  1. 

Bay  No.  V.  —  Coke  breeze,  from  gas  retorts,  —  5:1. 

Bay  No.  VI.  —  Clickers,  or  broken  rakings  from  boiler  plants, 
-3:2:1. 

Bay  No.  VII.  —  Thames  ballast,  or  gravel  dredged  from 
Thames,  —3:2:1. 

The  least  serious  damage  from  the  standpoint  of  reconstruction 
resulted  to  Bay  No.  V.  No  cracks  or  deflection  occurred,  but 
about  1  inch  of  the  soffit  material  was  washed  off  in  places,  by 
the  hose  stream.  Bays  Nos.  I,  II,  IV  and  VI  came  next  in  order 
of  excellence,  all  somewhat  cracked  and  sagged;  bay  No.  Ill 
was  even  more  damaged,  while  bay  No.  VII  suffered  the 
greatest  injury.  Regarding  the  latter,  "the  surface  was  dam- 
aged all  over  more  than  any  of  the  other  slabs,  the  greatest  depth 
being  about  2  inches.  A  hole  in  one  corner  permitted  daylight 
to  be  seen." 

Summary.  —  The    test    did    not  go  far  enough   to   draw 
definite  conclusions  except  to  show  the  entire  unreliability  of 


616         FIRE    PREVENTION    AND    FIRE    PROTECTION 

Thames  ballast  (or  gravel)  concrete  as  a  suitable  material  for 
this  method  of  construction. 


11 Red  Book"  No.  107.  —  Test  of  Thames  ballast  concrete  floor 
5  inches  thick,  with  4-inch  I-beam  joists  2  feet  4  inches  centers, 
and  wide-flange  I-beam  girders  placed  7  feet  centers.  The  con- 
struction suffered  a  permanent  deflection  of  4J  inches,  and  failed 
to  obtain  classification.  The  test  again  "  demonstrated  the  un- 
reliability of  ordinary  gravel  or  Thames  ballast  concrete  as  a 
fire-resisting  material  at  high  temperatures." 

"Red  Book"  No.  108.  —  Test  of  construction  identical  to  that 
described  in  No.  107,  the  only  difference  being  in  the  aggregate 
of  which  the  concrete  was  composed.  "The  test  clearly  demon- 
strated the  superiority  of  clinker  and  coke-breeze  concrete  over 
Thames  ballast."  The  floor  obtained  classification  "Full  Pro- 
tection, Class  B"  at  end  of  4  hours.  No  permanent  deflection 
was  apparent,  although  the  temperature  exceeded  the  standard 
requirements  by  90  degrees. 

" Red  Book"  No.  109  describes  a  test  of  concrete  floor  slabs 
reinforced  with  No.  10,  3-inch  expanded  metal.  The  concrete 
was  made  of  2.66  parts  brick  (broken  to  pass  a  1-inch  mesh  sieve), 
1.33  parts  sand,  and  1  part  cement.  One  bay  was  7  inches 
thick,  and  two  bays  were  6  inches  thick.  One  sheet  of  expanded 
metal  was  laid  in  each  bay,  1  inch  above  the  centering. 

Two  projecting  beams  or  girders  divided  the  three  panels. 

Beam  "A"  was  an  I-beam  surrounded  by  fine  concrete  (of 
same  mixture  as  above  but  with  the  aggregate  broken  finer),  in 
the  lower  portion  of  which  was  embedded  a  part  sheet  of  No.  6, 
li-inch  mesh  expanded  metal. 

Beam  "B"  was  an  I-beam  protected  by  2  inches  of  plaster, 
applied  on  f-inch  round  furring  rods  covered  with  expanded 
metal.  Hollow  spaces  existed  between  the  upper  and  lower 
beam  flanges. 

Summary.  —  Classification  "Full  Protection,  Class  B"  was 
obtained.  The  temperature  exceeded  the  required  standard  by 
260  degrees.  In  60  minutes  a  portion  of  the  concrete  casing  of 
beam  "A"  fell,  but  no  metal  was  visible.  In  2J  hours  there 
were  cracks  in  the  upper  surface  of  the  floor.  At  conclusion  of 
test,  beam  "A"  had  deflected  T4o  inch,  and  beam  "B"  If  inches. 
The  fire  did  not  pass  through  the  floor,  and  no  damage  was  done 
to  the  soffit  of  concrete  by  fire  or  water. 


CONCRETE   FLOORS   AND    REINFORCED    CONCRETE      617 

Reinforced-concrete  Slabs  and  Girders.  — -"Red  Book"  No.  106 
describes  a  test  of  the  "Coignet"  system  of  reinforcement  for 
slabs  and  girders.  The  concrete  was  a  clinker  mixture  made  of 
2|  parts  clinker,  1  part  sand,  and  1  part  Portland  cement.  The 
slabs,  which  were  6  inches  thick,  reinforced  with  f-inch  diameter 
rods  cambered  downwards  to  within  about  1  inch  of  the  wood 
centering,  were  supported  by  concrete  girders,  7  feet  5  inches 
centers,  reinforced  with  1^-inch  rods  which  were  placed  1J  inches 
up  from  the  soffit,  which  was  plastered. 

Summary.  —  Classification  "Full  Protection,  Class  A"  was 
obtained,  but  the  test  plainly  demonstrated  the  insufficiency  of 
the  protection  to  the  reinforcement  members.  The  application 
of  water  did  considerable  damage  to  the  beam  soffits,  and  also 
eroded  the  slab  soffits.  Neither  fire,  smoke  nor  water  passed 
through,  but  the  permanent  set  of  the  floor  was  5i7s  inches. 

"Red  Book"  No.  112  describes  a  second  test  of  the  "Coignet" 
system,  practically  identical  with  No.  106,  except  that  the 
aggregate  of  the  concrete  was  blast-furnace  slag,  and  the  sup- 
porting beams  were  5  feet  9  inches  centers. 

Summary.  —  The  application  of  water  knocked  much  concrete 
off  of  the  beam  soffits,  exposing  the  rods.  The  maximum  de- 
flection at  the  end  of  test  was  4T3o  inches,  the  permanent  set 
being  If  inches.  Neither  fire  nor  water  passed  through  the  floor, 
which  was  given  classification  "Full  Protection,  Class  B." 

"Red  Book"  No.  114  describes  a  reinforced  slab  and  beam 
floor  test  in  which  the  concrete  was  a  blast-furnace  slag  mixture. 
The  slab,  5f  inches  thick,  reinforced  with  indented  steel  bars, 
was  supported  by  concrete  beams  which  were  placed  7  feet  5 
inches  centers,  and  reinforced  with  square  bars  and  stirrups. 
The  larger  bars  were  placed  5  inches,  and  the  smaller  3  inches 
from  the  beam  soffits. 

Summary.  —  Classification  "Full  Protection,  Class  B"  was 
obtained.  The  application  of  water  dislodged  concrete  from 
the  beam  soffits,  exposing  the  bars.  The  slab  soffit  was  also 
eroded.  The  permanent  set  was  J  inch.  Neither  fire  nor  water 
passed  through  the  floor. 

"Lintel"  or  "Separately-moulded"  Floor.  — "Red Book"  No.  119 
describes  an  extremely  interesting  test  of  the  Herbst  "Armo- 
crete"  Tubular  System.  This  construction  is  equivalent  to  our 
so-called  "unit,"  "lintel"  or  "separately-moulded"  systems. 

The  floor,  which  was  22  feet  5  inches  long  by  10  feet  3  inches 


618 


FIRE    PREVENTION    AND    FIRE    PROTECTION 


span,  consisted  of  concrete  J-  webs  and  tubular  filling  blocks, 
as  shown  in  Fig.  246.  The  webs,  placed  11  inches  centers  across 
the  hut  from  wall  to  wall,  were  of  concrete  made  of  2  parts 
shingle,  1  part  sand,  and  1  part  Portland  cement.  Embedded 
therein,  1  inch  up  from  the  soffits,  were  If-inch  by  j\-inch  corru- 
gated reinforcing  bars.  The  tubular  filling  blocks  were  made 


FIG.  246.  —  "Armocrete"  Tubular  Floor  System. 

of  1\  parts  coke  breeze,  5  parts  sand,  and  1  part  cement.  They 
were  moulded  in  a  hand  press,  each  section  being  8  inches  long. 
A  l^-inch  layer  of  concrete  was  spread  over  the  whole  construc- 
tion, and  the  soffit  was  plastered.  Both  webs  and  tubes  were 
made  at  the  site. 

Summary  of  Test.  —  Classification  "Full  Protection,  Class  B  " 
was  obtained  under  a  temperature  exceeding  the  standard  re- 
quirements by  280  degrees.  The  application  of  water  produced 
no  effect  except  to  erode  some  of  the  plaster.  After  the  load  was 
removed,  transverse  cracks  were  observed  in  the  top.  The 
maximum  deflection  during  the  test  was  \  inch,  the  permanent 
set  being  TVS  inch.  Neither  fire  nor  water  passed  through. 

Load  Test.  —  A  subsequent  load  test  on  sample  slabs  of  the 
last  described  lintel  system  is  recorded  in  "  Red  Book  "  No.  125. 
Two  slabs  were  exactly  as  described  above,  2  feet  9  inches  wide, 
with  results  as  follows: 

Slab  A.  —  14-foot  span,  age  24  weeks,  failed  under  a  distributed 
load  of  1386  pounds  per  square  foot. 

Slab  C.  —  14-foot  span,  age  27  weeks,  failed  under  a  distributed 
load  of  706  pounds  per  square  foot. 

A  deeper  floor,  made  of  webs  13  i  inches  deep  reinforced  with 
two  2|-inch  by  f-inch  corrugated  bars,  was  also  tested  as  follows: 


CONCRETE   FLOORS  AND    REINFORCED    CONCRETE      619 

Slab  B.  —  28-foot  span,  age  27  weeks,  loaded  without  failure 
to  857  pounds  per  square  foot.  Deflection  3.95  inches. 

Load  Tests  of  Blast-furnace  Slag  Concretes.  —  Recent 
tests  have  been  made  by  the  Carnegie  Steel  Company  *  to  deter- 
mine the  value  of  blast-furnace  slag  as  an  aggregate  in  concrete 
work.  The  investigations  covered  tests  for  compression  only, 
on  1:3:6  concrete  blocks,  12  inches  diameter  and  16  inches 
high.  The  concretes  were  made  of  various  mixtures  of  Portland 
cement,  river-  and  slag-sand  and  aggregates,  the  latter  including 
gravel,  limestone,  machine  slag  and  bank  slag. 

Machine  Slag  is  made  by  running  molten  slag  from  the  blast 
furnace  onto  conveyor  pans  where  it  is  cooled  by  water  spray 
before  dumping.  The  pieces  are  thin,  ranging  in  size  up  to 
about  1  inch. 

Bank  Slag  is  air-cooled  blast-furnace  slag,  excavated  from 
old  waste  banks.  It  is  then  crushed  and  screened,  the  pieces 
ranging  from  \  inch  to  1  inch.  Bank  slag  No.  2  is  the  same,  ex- 
cept that  the  pieces  run  to  2J  inches  in  size. 

The  following  conclusions  were  given  as  the  result  of  these 
tests : 

(1)  The  mixtures   containing  river  sand  and  gravels  were 
regarded  as  standard. 

(2)  Generally  bank  slags  tested  higher  than   either  gravel 
or  limestone. 

(3)  Bank  slag  No.  1  with  river  sand  developed  the  greatest 
strength  of  all  the  coarser  aggregates. 

(4)  Bank  slag  No.  2  with  river  sand  ranks  second. 

(5)  All  slag  aggregates  compare  favorably  with  the  gravel 
standard. 

(6)  Both  bank  slag  aggregates  with  either  river  sand  or 
slag  sand  No.  2  can  be  recommended  for  general  work. 

(7)  Machine  slag  is  recommended  for  lighter   construction 
where  maximum  strength  is  not  essential. 

(8)  Bank  slag  screenings,   and    especially    the    No.    2  or 
coarser   grade,    developed   remarkably   high   strength   and   are 
probably  the  materials  par  excellence  for  reinforced   concrete 
when    lightness    of    construction    with    maximum    strength    is 
required. 

(9)  Many  of  these  slag  products  have  already   been  used 
in  practice  for  several  years,  and  compare  favorably  with  other 
materials. 

*  See  "Furnace  Slags  in  Concrete;  a  Series  of  Tests  to  Determine  the  Prac- 
ticability of  Blast  Furnace  Slags  for  Use  in  Concrete,"  by  Carnegie  Steel  Com- 
pany, Pittsburgh,  Pa.,  1911. 


620         FIRE    PREVENTION    AND    FIRE    PROTECTION 

Concrete  Floors  in  San  Francisco  Buildings.  —  Several 
opinions  regarding  the  action  of  concrete  in  buildings  which 
passed  through  the  San  Francisco  conflagration  have  previously 
been  given  (see  Chapter  VII,  page  245).  As  regards  floor  con- 
structions particularly,  various  types  were  compared  by  Mr. 
Himmelwright  as  follows: 

The  segmental  cinder  concrete  arch,  in  short  spans  (8  feet 
or  less),  where  the  concrete  was  originally  of  good  qualit}^  de- 
veloped the  best  fire-resisting  qualities  and  strength.  This 
material  and  this  form  of  using  it  proved  vastly  superior  to  any 
other  used  for  fireproofing  purposes.  This  method  was  used 
in  the  Hotel  St.  Francis,  and  in  the  ground  floor  of  Haas'  Candy 
Factory,  at  the  corner  of  Mint  avenue  and  Jessop  street,  and 
not  a  single  square  foot  of  the  floor  arching  in  these  buildings  was 
damaged  in  the  least  by  the  fire. 

The  next  best  fire-resistance  was  shown  by  the  short-span 
(8  feet  or  less),  cinder-concrete,  flat-slab  floor  construction,  in 
which  steel  reinforcing  metal  was  used  in  tension.  This  method 
and  material  were  used  in  the  Merchants'  Exchange,  in  which  the 
damage  by  fire  was  inappreciable. 

The  next  in  order  of  fire-resistance  was  the  same  short- 
span,  flat-slab  method  of  reinforced  concrete  in  which  stone  and 
gravel  aggregates  were  used.  This  method  and  material  were 
used  quite  extensively,  the  best  results  having  been  shown  in 
the  Mutual  Savings  Bank  Building,  the  Bush  Street  and  South 
offices  of  the  Pacific  States  Telephone  Company  and  many 
others. 

The  next  method  in  the  order  of  fire-resistance  was  the  re- 
inforced stone-concrete  construction  proper  in  long  spans,  and 
where  rolled-steel  girders  and  beams  were  generally  omitted. 
Where  this  method  was  used,  a  very  slight  attack  of  fire  was 
generally  sufficient  to  cause  the  rupture  of  the  concrete  under- 
neath the  reinforcing  metal,  so  that  it  fell  away,  exposing  the 
metal.  There  were  comparatively  few  buildings,  however,  in 
which  this  method  of  construction  was  used. 


Conclusions.  —  The  severe  fire  and  water  tests  of  the  British 
Fire  Prevention  Committee  described  above  show  conclusively 
that  concrete  floors  may  be  made  to  possess  a  very  high  degree 
of  fire-resistance,  and,  withal,  a  high  load-carrying  capacity  under 
severe  conditions.  The  standard  requirements  of  the  British 
Fire  Prevention  Committee  for  "Full  Protection,  Class  B" 
viz.,  1800  degrees  for  4  hours,  under  a  load  of  280  pounds  per 
square  foot  —  are  even  somewhat  more  severe  than  the  require- 
ments of  the  New  York  Building  Department  —  viz.,  1700 
degrees  for  4  hours,  under  a  load  of  150  pounds  per  square  foot. 


CONCRETE   FLOORS   AND    REINFORCED    CONCRETE       621 

Any  construction  which  can  successfully  pass  such  tests  will 
most  certainly  withstand  any  ordinary  actual  tests. 

It  has  been  shown  in  Chapter  VII  that  stone-  or  gravel-concrete 
loses  50  per  cent,  or  more  of  its  strength  under  a  temperature 
of  1500  degrees,  sustained  for  three  hours.  Also,  that  surface 
dehydration  will  occur  under  heat  to  a  greater  or  less  depth,  and 
that  hose  streams  will  generally  erode  more  or  less  surface  ma- 
terial. Notwithstanding  these  facts,  it  should  be  remembered 
that  fires  in  buildings  will  seldom  develop  temperatures  equal 
to  those  maintained  in  the  tests  above  described,  at  least  for 
any  considerable  period  of  time.  Actual  fires  in  buildings 
seldom  develop  maximum  temperatures  for  more  than  half  an 
hour. 

The  foregoing  tests,  however,  serve  to  emphasize  several 
points,  —  some  of  which  were  touched  on  in  Chapter  VII,  — 
which  are  vital  from  the  standpoint  of  minimum  damage,  or 
reconstruction. 

"Full  Protection"  vs.  Reconstruction.  —  "Full  protection/7  as 
far  as  classification  is  concerned,  may  mean  full  destruction  as 
far  as  reconstruction  is  concerned.  Thus  the  floor  described  in 
"Red  Book"  No.  106,  while  passed  for  classification,  suffered  a 
permanent  deflection  of  5T7g-  inches.  The  floor  had  satisfactorily 
fulfilled  its  protective  function,  but  was  damaged  beyond  success- 
ful repair.  As  far  as  the  floor  itself  is  concerned,  such  a  result 
in  an  actual  building  would  mean  even  more  than  the  total  loss 
of  the  construction,  for  the  reason  that  it  would  have  to  be  torn 
out  and  built  anew.  Thus,  as  with  other  materials,  the  question 
of  successful  reconstruction  becomes  a  factor  to  be  reckoned  with 
and  in  reinforced-concrete  work  this  factor  assumes  particular 
importance. 

The  structural  integrity  of  reinforced  concrete  depends  both 
upon  the,  unbroken  continuity  of  the  concrete  and  the  perfect 
bond  or  adhesion  between  the  concrete  and  the  reinforcement. 
If  either  of  these  conditions  has  been  destroyed,  as  by  the  crack- 
ing or  serious  deflection  of  the  construction,  or  by  the  destruction 
or  dehydration  of  any  considerable  portion  of  the  soffit  material 
—  i.e.,  the  vital  protective  covering,  —  successful  repair  becomes 
practically  impossible.  This  is  due  to  the  difficulty  of  adequate 
reconstruction,  for  even  though  the  structural  integrity  had  not 
been  sufficiently  impaired  to  require  entire  replacement,  the  ex- 
posure of  the  reinforcement  or  the  vitiation  of  the  protective 


622         FIRE    PREVENTION    AND   FIRE    PROTECTION 

layer  would  require  making  good  all  damaged  material  to  de- 
velop capacity  to  withstand  a  second  attack  by  fire.  This 
cannot  easily  be  accomplished. 

An  adequate  bond  between  old  and  new  concrete  is  not 
attainable.  Simply  plastering  the  missing  material  on  to  the 
under  side  of  a  slab  is  but  a  partial  remedy,  for  the  next  fire  will 
speedily  strip  it  off.  Spreading  expanded  metal  under  the  dam- 
aged slab,  securing  it  by  numerous  expansion  bolts  and  stiffening 
it  properly,  then  imbedding  it  in  cement  plaster,  would  be  practi- 
cally a  complete  remedy,  but  it  would  be  expensive  and  laborious. 
Wrapping  a  damaged  beam  or  girder  with  expanded  metal,  well 
secured,  and  covering  it  with  cement  plaster,  is  relatively  less 
expensive  and  would  be  an  adequate  restoration.  Even  where 
expanded  metal  is  used,  however,  if  the  bars  have  been  exposed, 
or  nearly  exposed,  the  power  to  transmit  full  stress  into  the  con- 
crete above  is  irrevocably  lost,  and  the  expanded  metal  and 
cement  cannot  restore  the  structural  integrity;  they  will,  at  the 
utmost,  only  restore  the  fire-resisting  qualities.* 

The  means  whereby  the  structural  integrity  shall  be  amply 
preserved,  and  whereby  the  resultant  damage  by  fire  shall  be 
confined  to  surface  or  remedial  loss,  are,  therefore,  important,  and 
should  be  looked  upon  in  the  nature  of  insurance. 

Deflection.  —  The  British  Fire  Prevention  Committee's  tests 
show  that  excessive  deflection  or  permanent  set  may  be  caused 
by  the  use  of  improper  aggregates,  or  by  insufficient  protection' 
of  the  reinforcement.  Thus  "Red  Books"  Nos.  107  and  108 
describe  identical  constructions,  but  with  different  aggregates. 
The  gravel  aggregate  resulted  in  a  deflection  of  4|  inches;  the 
clinker  and  coke-breeze  concretes  gave  no  permanent  deflection. 
The  tests  described  in  "Red  Books''  Nos.  106  and  112  show 
that  even  a  clinker  concrete,  when  of  insufficient  protective  thick- 
ness, will  result  in  an  excessive  permanent  set. 

Protection  of  Reinforcement,  —  not  only  affects  the  deflection, 
as  above,  but  also  principally  determines  the  practicability  and 
cost  of  reconstruction.  The  tests  before  quoted  show  pretty 
conclusively  that  usual  commercial  constructions  do  not  provide 
sufficient  soffit  protections,  and  that  the  thicknesses  prescribed 
in  Chapter  VII  (see  page  249),  should  be  increased  rather  than 
skimped. 

Reinforced  beams  and  girders  are  especially  susceptible  to 
injury  under  high  temperatures.  The  reason  is  undoubtedly 

*  Captain  John  Stephen  Sewell. 


CONCRETE   FLOORS   AND    REINFORCED    CONCRETE      623 

the  same  as  has  been  pointed  out  in  connection  with  flush  vs. 
paneled  ceilings.  The  tests  described  in  "Red  Books"  Nos.  106, 
112  and  114,  all  showed  the  insufficiency  of  the  protection  — 
usually  about  1J  inches  —  afforded  the  girder  reinforcement. 
The  need  of  internal  wrappings  of  expanded  metal  at  the  soffits, 
or  other  mechanical  bond,  was  indicated. 

The  insufficiency  of  a  2-inch  plaster  protection  was  shown  in 
test  No.  109. 

Aggregates.  —  The  tests  show  varying  results  with  the  same 
aggregate,  but  in  general,  they  indicate  the  unsuitability  of 
gravel  and  granite,  —  the  suitability  of  clinker,  coke  breeze  and 
broken  brick  for  ordinary  conditions,  —  and  the  fitness  of  blast- 
furnace slag  for  reliable  results. 

Advantages  and  Disadvantages  of  Concrete  Floors.  - 
The  advantages  incident  to  concrete  floor  construction  include: 

1.  Usual   lowest   cost,    except,    possibly,    in    the   immediate 
vicinity  of  tile  factories.     Of  brick,  hollow-tile  or  concrete  floors 
in  connection  with  a  framework  of  steel,  the  latter  combination 
will  generally  prove  the  cheapest. 

2.  The  use  of  materials  which  do  not  have  to  be  made  to 
order,  but  which  are  readily  obtainable  in  all  localities. 

3.  The  adaptability  of  concrete  to  irregular  framing,  as  in 
those  buildings  which  must  be  designed  to  suit  irregular  lot 
lines. 

4.  Superior  beam  and  girder  protections,  as  previously  pointed 
out  in  this  chapter. 

5.  Ease  of  making  floors  waterproof  —  of  great  importance 
where  valuable  stocks  are  carried. 

6.  The  uniform  protection  of  all  steelwork,  frame  or  rein- 
forcing, against  corrosion,  except,  possibly,  where  cinder  concrete 
is  used. 

7.  The  ease  of  reconstruction  after  fire,  unless  the  damage 
has  been  severe. 

Disadvantages  include: 

1.  The  dependence  on  conditions  of  weather  during  building 
operations,  often  materially  increasing  the  time  necessary  for 
erection,  unless  temporary  closing  in  and  artificial  heat  are  used. 

2.  The  interference,  during  building  operations,  with  other 
branches  of  work,  owing  to  dripping. 

3.  The  slow  drying  out  of  concrete,  thus  delaying  the  placing 
of  trim  —  often  a  very  serious  item.      Much  trim  in  concrete 


624         FIRE    PREVENTION   AND    FIRE    PROTECTION 

buildings  has  had  to  be  extensively  repaired  or  entirely  replaced, 
because  put  in  before  the  building  was  thoroughly  dry. 

4.  Increased  weight  in  long-span  construction  —  often  much 
greater  than  for  long-span  tile  systems. 

5.  Difficulty  of  reconstruction  in  case  of  serious  fire  damage, 
as  entire  bays  often  have  to  be  replaced. 


CHAPTER  XIX. 

COMBINATION  TERRA-COTTA  AND  CONCRETE 
FLOORS. 

COMBINATION  floors  of  hollow  tile  and  reinforced  concrete  have 
been  successfully  used  in  many  instances,  and  it  is  not  improbable 
that  the  greatest  possibilities  for  future  improvement  in  floor 
construction  may  lie  in  this  direction. 

The  recommendations  of  this  type  of  floor  comprise : 

(a)  The  applicability  of  the  system  to  either  reinforced  con- 
crete construction  or  to  steel  skeleton  construction. 

(b)  The  reduction  in  weight  attendant  upon  the  use  of  hollow 
tile  fillers,  whereby  a  combination  floor  of  adequate  depth  and 
rigidity  may  be  secured  at  less  weight  than  where  an  all-concrete 
construction  is  used;   and 

(c)  Simplicity  of  erection  and  low  cost  of  centering. 
National  Fire  Proofing  Company's  Combination  Floor.  — 

An  isometric  view  of  this  construction  is  shown  in  Fig.  247.  A 
flat  centering  is  first  provided,  but,  as  the  hollow-tile  blocks  are 
12  inches  wide,  it  is  only  necessary  to  support  these  along  their 
edges.  Hence  the  centering  is  made  of  about  8-inch  planks  laid 
about  8  inches  apart,  as  shown  in  Fig.  247.  This  arrangement 
effects  a  considerable  saving  in  the  cost  of  centering.  Continuous 
courses  of  end-construction  blocks  are  then  laid  with  4-inch  open 
troughs  or  spaces  between,  in  which  are  placed  reinforcing  rods. 
Concrete  is  then  poured  between  the  courses  of  tile  which  thus 
act  as  side  centering  to  hold  the  concrete  in  place  until  it  has  set. 
An  additional  top  layer  of  concrete  is  usually  added  over  the 
entire  surface,  to  give  the  required  strength  for  long  spans. 

Fig.  248  shows  the  combination  floors  used  in  the  skeleton- 
construction  Berkeley  Building,  Boston,  Codman  and  Despra- 
delle,  architects.  Spans  were  employed  up  to  24  feet. 

Fig.  249  illustrates  the  15-foot  bays  used  in  the  Keany  Square 
Trust  Building,  Boston,  in  combination  with  reinforced-concrete 
columns  and  girders.  A  load  test  made  in  that  building  resulted 

625 


626         FIRE    PREVENTION   AND    FIRE    PROTECTION 


COMBINATION  TERRA-COTTA  AND  CONCRETE  FLOORS     627 

in  the  carrying  of  a  load  of  520  pounds  per  square  foot  over  an 
area  of  65  square  feet,  without  deflection. 


,  „       ,  3V6"Stone  Concrete  Fin 


I  ^sfcsiifo^ 


FIG.  248.  —  Combination  Floors  as  used  in  Berkeley  Building,  Boston. 

A  similar  combination  floor  used  in  connection  with  reinforced- 
concrete  girders  and  columns  was  employed  in  the  new  Marl- 
borough-Blenheim  Hotel  at  Atlantic  City,  N.  J.,  for  a  description 
of  which,  see  Engineering  News,  March  8,  1906. 


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FIG.    249.  —  Combination    Floors   and   Reinforced   Concrete   Girders,    Keany 
Square  Trust  Bldg.,  Boston. 

The  weights  per  square  foot  and  safe  live  loads  for  varying 
spans  and  constructions,  as  used  by  the  National  Fire  Proofing 
Company,  are  as  follows: 


628 


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COMBINATION  TERRA-COTTA  AND  CONCRETE  FLOORS     629 


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630         FIRE    PREVENTION    AND    FIRE    PROTECTION 

Fig.  250  shows  a  combination  floor  of  the  above  type,  with 
the  soffits  of  the  concrete  joists  protected  by  means  of  soffit  tile 
of  special  pattern. 


FIG.  250.  —  Combination  Floor,  Concrete  Joists  protected  by  Soffit  Tile. 

Combination  Floors  with  Plaster-block  Fillers.  —  A  long- 
span  floor  system  made  of  a  combination  of  reinforced  concrete 
and  plaster-block  fillers  is  described  by  Mr.  Emile  G.  Perrot  in 
the  "  1910  Proceedings  of  the  National  Association  of  Cement 
Users."  The  floors  in  question  were  built  for  the  Philadelphia 
Turngemeinde  Club  House,  of  53  feet  1J  inches  clear  span.  In 
brief,  the  construction  consists  of  reinforced-concrete  T-girders, 
placed  13  feet  9  inches  centers,  spanning  from  wall  to  wall,  be- 
tween which  the  floor  panels  are  made  of  5-inch  by  12-inch  rein- 
forced-concrete  joists  alternating  with  fillers  or  centers  made  of 
12-inch  by  12-inch  plaster  blocks  in  sections  3  feet  long.  A 
2-inch  reinforced-concrete  slab  covers  the  entire  area. 

Combination  Floor  Used  in  War  College  Building,  Wash- 
ington, D.  C.  —  The  combination  hollow-tile  and  concrete  floor 
designed  by  Captain  John  S.  Sewell  for  use  in  the  War  College 
Building  at  Washington,  D.  C.,  is  illustrated  in  Fig.  251.  Re- 
garding this  construction  Captain  Sewell  states  as  follows:* 

This  floor  is  50  per  cent,  deeper  than  a  reinforced  slab 
would  have  been.  The  patented  bar  shown  is  not  entirely  satis- 
factory, in  either  the  shape  of  its  cross-section  or  in  the  distri- 
bution of  web  members.  These  are  rigidly  attached,  however, 
and  the  bar  gives  results  much  better  than  any  attainable  before 
its  introduction.  This  floor  was  made  with  a  view  to  resisting 
fire  without  other  damage  than  the  loss  of  ordinary  plaster  from 
the  ceiling;  therein  it  differs  materially  from  commercial  stand- 
ards. But  the  type  can  be  made  as  light  as  the  flimsiest  of  hol- 
low-tile arches.  For  a  given  degree  of  structural  strength  and 
fire-resisting  qualities  the  writer  believes  it  to  be  the  cheapest 
floor  available  at  the  present  time.  .  .  . 

*  See  "The  Fire-Resisting  Qualities  of  Reinforced  Concrete,"  Insurance 
Engineering,  Vol.  X,  p,  509, 


COMBINATION  TERRA-COTTA  AND  CONCRETE   FLOORS    631 


The  tiles  in  this  type  of  floor  are  set  loose  upon  the  center- 
ing before  the  concrete  is  placed;  the  joints  are  imperfectly  filled, 
which  is  an  advantage,  since  the  tiles  have  no  structural  duty  to 
perform,  and  are  freer  to  expand  when  heated,  so  they  are  not 
so  likely  to  lose  their  exposed  webs  as  when  they  are  built  into 
flat  arches. 


ConcreteXplaster 

CROSS  SECTION   ON   X-X 


—16- 


LONGITUDINAL  SECTION  THROUGH  CONCRETE  JOIST 


FIG.  251.  —  Combination  Floor  as  used  in  War  College  Building, 
Washington,  D.  C. 

Fire  Tests  and  Efficiency  of  Combination  Floor  Systems. 

—  The  few  fire  tests  of  combination  floors  which  have  been  made 
have  been  purely  experimental  and  not  actual.  The  author  is 
not  aware  that  any  such  system  has  ever  been  subjected  to  a 
fire  and  water  test  of  any  severity  by  the  burning  of  a  building. 

"Red  Book"  No.  103  of  the  British  Fire  Prevention  Committee 
describes  a  test  made  on  a  combination  floor  somewhat  similar 
to  that  shown  in  Fig.  249,  except  that  the  terra-cotta  blocks  were 
square  in  cross-section,  6  inches  by  6  inches,  with  one  void  or 
cell  each.  The  total  thickness  of  the  floor  was  SI  inches,  the 
concrete  joists  being  reinforced  with  J-inch  diameter  rods.  The 
construction  obtained  classification  "Full  Protection,  A,"  but 
the  application  of  water  washed  off  much  of  the  soffit  plastering, 
and  exposed  some  of  the  reinforcing  rods.  Neither  fire  nor  water 
passed  through  the  floor,  although  a  permanent  set  of  3  inches 
resulted. 

The  remarkable  fire  and  load  tests  developed  by  the  "Armo- 
crete"  system  (see  page  617),  indicate  that  combination  floors 


632         FIRE    PREVENTION    AND    FIRE    PROTECTION 

of  a  type  similar  to  those  shown  in  Figs.  250  and  251,  wherein 
tile  fillers  are  used  and  the  concrete  joists  are  protected  by  terra- 
cotta soffit  tile,  should  possess  even  greater  fire-resistance.  As 
to  the  fire-resisting  possibilities  of  the  combination  construction 
shown  in  Fig.  251,  and  the  great  improvements  which  may  yet 
be  made  along  such  lines,  Captain  Sewell  states  as  follown:* 

Tests  recently  made  of  a  pattern  of  tile  used  at  the  War 
College  indicate  that  floor  tile  subjected  to  a  fire  test  will  stand 
better  if  there  is  but  one  interior  hole  through  the  tiles,  all  of  the 
material  which  would  otherwise  be  used  in  the  interior  webs 
being  concentrated  in  the  outer  webs,  and  the  opening  in  the 
tile  being  of  circular  or  elliptical  shape,  depending  on  the  height 
and  width  of  the  tile.  For  floor  arches  between  steel  beams 
such  a  tile  as  this  one  would  have  to  be  used  on  the  end-construc- 
tion plan.  A  specially  heavy  skewback  should  be  designed  to 
go  with  it,  or  else  the  end  tile  should  be  cut  to  fit  the  profiles  of 
the  beam.  The  tile  themselves  being  so  heavy,  the  latter 
method  of  obtaining  a  skewback  would  probably  make  the  arch 
more  than  strong  enough  to  carry  its  load,  and  where  carefully 
done,  might  afford  adequate  fire  protection  to  the  beams,  al- 
though for  that  purpose  a  specially  designed  extra  heavy  side- 
construction  skewback  would  be  better,  and  should  on  the  whole 
be  recommended  even  in  connection  with  the  heavy  end-con- 
struction arches  described. 

It  is  probable  that  either  a  good  concrete  floor  with  the  right 
kind  of  ceiling  below  it,  or  a  heavy  tile  floor  such  as  that  herein 
described,  would  come  through  almost  any  fire  with  no  damage 
except  the  loss  of  the  ceiling  plaster.  These  two  types  may, 
therefore,  be  taken  as  equivalent  in  efficiency;  they  will  probably 
be  about  equal,  also  in  first  cost. 

*  United  States  Geological  Survey  Bulletin  No.  324,  page  121. 


CHAPTER  XX. 
WALL   CONSTRUCTION. 

Types  of  Exterior  Walls.  —  Exterior  walls  for  fire-resisting 
buildings  may  be  either  load-supporting,  self-supporting,  or 
veneer,  —  that  is,  dependent  for  support  upon  a  steel  framework. 

Load-supporting  Walls.  —  Before  the  introduction  of  steel- 
skeleton  construction,  exterior  walls  were  generally  built  of  solid 
masonry,  and  were  designed  to  carry  their  proper  wall-,  floor-  and 
roof-loads  without  the  aid  of  metal  columns.  This  still  consti- 
tutes the  ordinary  practice  in  buildings  with  brick  or  stone  walls 
of  moderate  height,  whether  of  fire-resisting  or  non-fire-resisting 
construction.  Eight  or  ten  stories  is  the  usual  maximum  height 
for  load-supporting  walls,  as  above  this  height  the  piers  become 
heavy,  adding  materially  to  the  foundation  weights,  while  their 
bulk  consumes  too  much  floor  area,  and  reduces  the  size  of  the 
openings  required  by  present  practice  for  ample  light  and  air. 

In  addition  to  the  data  given  in  this  chapter,  see  also  Chapter 
XXIV  for  walls  of  residences,  and  Chapters  IV  and  XXV  for 
walls  in  mills,  warehouses,  factories,  etc. 

Self-supporting  Walls.  —  Self-supporting  exterior  walls  were 
employed  in  the  earlier  examples  of  skeleton-construction  build- 
ings. Such  walls  served  to  carry  their  own  weight  only,  while 
all  floor-  and  roof-loads  were  supported  on  metal  columns  placed 
within  the  walls.  Self-supporting  walls  have  been  employed  in 
some  cases  to  a  height  as  great  as  sixteen  stories,  and  their  use 
is  still  common  in  buildings  of  from  eight  to  twelve  stories;  but 
the  objections  of  weight  and  bulk  attendant  upon  their  use  in- 
crease rapidly  with  the  height. 

Veneer  or  Curtain  Walls,  entirely  dependent  for  support  upon 
the  steel  frame,  have  made  possible  the  design  and  construction 
of  the  highest  buildings  now  erected.  The  masonry  wall,  which 
has  usually  been  the  most  important  factor  in  building  con- 
struction, now  becomes  but  a  veneer,  serving  as  an  architectural 
envelope,  and  as  a  protective  covering  against  weather,  corrosion 

633 


634         FIRE    PREVENTION    AND    FIRE    PROTECTION 

and  fire.  The  walls  are  supported  on  the  steelwork  at  each 
floor  level,  thus  making  a  series  of  walls,  each  a  single  story  in 
height.  This  method  results  in  a  very  material  saving  of  floor 
area  and  weight,  due  to  the  reduced  thickness  of  the  walls. 

Veneer  walls  are  not  suitable,  from  a  fire-resisting  standpoint, 
for  use  in  such  buildings  as  stores,  warehouses  or  manufactories, 
as  veneer  construction  is  not  ordinarily  heavy  enough  either  to 
resist  serious  damage  by  fire  or  to  confine  fire  resulting  from  the 
combustion  of  large  quantities  of  merchandise. 

Self-supporting  vs.  Veneer  Walls.  —  The  Baltimore  and 
San  Francisco  conflagrations  both  show  conclusively  that  self- 
supporting  masonry  walls  suffer  less  from  fire  damage  than  do 
veneer  or  curtain  walls  as  ordinarily  built. 

The  self-supporting  brick  walls  built  up  from  the  founda- 
tions were  structurally  in  good  condition,  except  some  minor 
cracking  over  door  and  window  lintels.  Such  walls,  when  sub- 
stantially constructed,  seem  to  be  superior  to  curtain  walls 
carried  on  the  steel  frames.* 

Captain  Sewell,  in  his  report  to  the  Chief  of  Engineers,  U.  S.  A., 
discusses  the  reasons  for  the  superiority  of  self-supporting  walls 
as  follows: 

I  believe  that  better  results  would  be  obtained  by  building 
the  exterior  walls  continuously  from  the  foundation  up,  anchor- 
ing them  carefully  to  the  steel  frame  to  prevent  buckling.  The 
beams  carrying  the  walls  are  often  so  near  the  surface,  especially 
where  they  act  as  lintels,  that  in  a  long-continued  fire  they  get 
hot  enough  to  expand  and  bend ;  this  will  wreck  the  wall,  if 
nothing  else  does.  If  the  weight  of  brickwork  is  assumed  at  125 
pounds  per  cubic  foot,  and  its  safe-working  load  at  20  tons  per 
square  foot,  a  wall  of  uniform  thickness  and  320  feet  high  will  be 
safe  under  its  own  weight,  so  far  as  crushing  is  concerned.  With 
a  very  moderate  increase  in  thickness  near  the  bottom,  and 
thorough  anchorage  to  the  steel  frame  at  all  points,  a  self-support- 
ing brick  wall  is  entirely  practicable  for  any  steel-frame  building. 
Its  only  drawback  is  the  time  required  to  build  it,  for  it  could 
not  be  started  on  a  number  of  levels  at  the  same  time.  This, 
however,  would  probably  result  in  better  work.  The  modern 
building,  erected  in  record-breaking  time,  is  never  a  model  of 
workmanship,  and  often  it  contains  defects  that  reduce  the  factor 
of  safety  almost  to  unity.  The  standard  of  work  that  prevails 
in  these  hastily  erected  structures  would  not  be  tolerated  for  a 
moment  in  general  engineering  works. 

*  Report  of  the  National  Fire  Protection  Association  Committee  on  Balti- 
more Conflagration. 


WALL    CONSTRUCTION  635 

.But  from  the  standpoint  of  reconstruction,  the  use  of  the 
skeleton  type  of  building  with  veneer  walls  is  to  be  preferred, 
provided  the  walls  are  made  of  materials  of  a  character  and  thick- 
ness adequate  to  protect  the  steel  frame. 

In  both  load-supporting  and  self-supporting  walls,  the  damage 
of  portions  by  fire  may  mean  the  attendant  removal  of  large  areas 
of  uninjured  wall  at  the  time  of  reconstruction,  while  their  load- 
bearing  capacity  in  the  former  type  renders  them  more  liable  to 
failure.  In  load-supporting  walls,  the  bracing  necessary  to 
prevent  collapse  is  very  important,  as  failure  of  the  walls  would 
mean  great  damage  to  other  portions  of  the  structure. 

With  veneer  walls,  parts  damaged  by  fire  may  be  removed 
and  restored  with  facility,  as  the  method  of  construction  allows 
the  walls  to  be  readily  replaced  for  only  such  stories  or  portions 
of  stories  as  receive  injury. 

Materials.  —  The  materials  used  for  exterior  walls  should 
preferably  be  brick,  terra-cotta,  or  concrete,  though  iron  or  steel 
and  stone  are  also  extensively  employed.  The  fire-resisting 
qualities  of  these  materials  have  been  discussed  at  length  in 
Chapter  VII.  In  designing  and  detailing  exterior  walls,  the 
following  points  should  be  considered: 

Ironwork.  —  Ornamental  ironwork  is  frequently  employed, 
especially  for  store  fronts  and  entrances,  where  cast-iron  pilasters, 
facias,  sills,  panels,  etc.,  are  required  by  the  design.  A  very 
common  detail  is  to  make  store  fronts  run  up  through  two  stories, 
with  paneled  or  ornamented  cast-iron  pilasters  covering  the 
piers,  a  deep  facia  or  cornice  at  the  third  floor  level,  and  panels 
at  the  second  floor  level  between  the  piers.  For  such  purposes, 
cast-iron  is  much  to  be  preferred,  as  cast  metal  will  retain  its 
shape  and  position  far  better  than  thin  plates  of  wrought-iron 
or  steel.  In  such  constructions,  an  efficient  fire-resisting  backing 
must  be  used  to  protect  any  structural  steel  members  behind 
the  facings,  in  case  the  latter  should  fail,  and  to  prevent  the 
penetration  of  high  temperatures.  Requirements  of  this  nature 
are  frequently  called  for  in  local  building  ordinances. 

Regarding  exterior  cast-iron  work,  etc.,  see  also  paragraph 
" Improper  Enclosing  Walls,"  Chapter  XV,  page  507,  and  para- 
graphs "Lintels  '  and  "Mullions"  in  this  chapter. 

Stone.  —  Thin  slabs  of  marble,  limestone,  or  granite  should 
never  be  relied  upon  to  form  a  protection  of  steelwork  against 
fire.  Four-inch  or  five-inch  slabs,  such  as  are  often  used,  form 


636         FIRE    PREVENTION    AND    FIRE    PROTECTION 

very  little  protection,  and  even  where  the  facing  is  made  of  a 
greater  thickness,  it  should  be  backed  up  with  brickwork  or  terra- 
cotta, so  as  to  protect  efficiently  the  structural  steel  in  case  the 
stone  veneer  is  destroyed.  The  support  of  such  fire-resisting 
backing  should  be  arranged  so  as  to  be  entirely  independent  of 
the  facing,  so  that  the  destruction  of  the  latter  would  not  cause 
the  failure  of  the  protective  covering. 

If  limestone,  marble,  or  granite  is  used  for  the  exterior,  the 
design  should  be  such  that  the  strength  of  the  structure  does  not 
rely  upon  such  masonry,  unless  used  in  substantial  mass.  Even 
so,  Fig.  43  illustrates  the  danger  attendant  upon  the  use  of  granite 
in  columns  as  large  as  four  square  feet  area. 

Many  fires  have  caused  great  damage  to  limestone,  marble 
and  granite  facades,  as  in  the  Chicago  Athletic  Club  Building, 
the  Home  Life  Building,  and  very  many  other  structures  in 
Baltimore,  San  Francisco,  etc.  Fig.  37  illustrates  the  condition 
of  the  first  story  granite  walls  of  the  Baltimore  and  Ohio  Railroad 
Company's  Building  after  the  Baltimore  fire,  and  Fig.  36  shows 
a  marble  column  in  the  entrance  rotunda  of  the  Calvert  Building 
after  the  same  fire.  Such  experiences  point  to  the  desirability 
of  employing  the  pure  skeleton  construction  if  the  use  of  stone  is 
introduced  to  secure  architectural  effects.  The  stonework  would 
then  be  free  from  any  load-carrying  functions,  and  the  walls 
would  be  divided  story  by  story.  Damaged  material  could  be 
replaced  without  disturbing  unaffected  areas. 

Stone  templates  and  bond  stones  should  not  be  employed  in 
masonry  walls.  Cast-iron  bearing  plates  or  levelers  are  far 
preferable.  Captain  Sewell  found  in  his  examination  of  the 
San  Francisco  City  Hall  after  the  San  Francisco  conflagration 
that 

A  number  of  girders  or  lintels  rested  upon  stone  templates 
which  were  exposed  at  the  face  of  the  wall.  All  such  templates 
that  were  subjected  to  heat  were  badly  spalled  and  shattered 
and  one  or  two  of  them  had  failed  sufficiently  to  permit  the  ends 
of  the  girders  to  settle  an  inch  or  more.* 

Stone  of  any  kind  should  be  classed  as  fragile  and  especially 
susceptible  to  damage  when  exposed  to  severe  heat.  From  a 
fire. protection  viewpoint  it  is  unsuitable  both  for  wall  and  pier 
construction  and  for  exterior  or  interior  finish. f 

*  United  States  Geological  Survey,  Bulletin  No.  324,  page  88. 
t  Report  of  National  Fire  Protection  Association  Committee  on  Baltimore 
Fire. 


WALL   CONSTRUCTION  637 

Brickwork.  —  Unless  the  construction  is  of  reinforced  con- 
crete, brick  masonry  is  usually  employed  for  the  body  of  the 
exterior  walls.  These  should  be  of  sufficient  thickness  and  rigid- 
ity, and  built  of  the  best  materials.  See.  Chapter  VII  and  later 
paragraphs  " Thickness"  and  " Anchorage,"  etc.,  in  this  chapter. 

Four  inches,  or  a  single  thickness  of  brick,  is  sometimes  con- 
sidered an  efficient  covering  for  steel  members,  but  8  inches  is 
much  to  be  preferred  as  a  minimum,  both  on  account  of  fire- 
resistance  and  protection  against  corrosion.  Cement  mortar 
should  always  be  used  in  the  best  classes  of  work,  especially 
where  it  comes  in  contact  with  steelwork. 

To  insure  a  minimum  damage  by  fire,  the  use  of  plain  surfaces 
and  rounded  corners  at  salient  angles  is  preferable. 

Ornamental  Terra- Cotta  is  very  extensively  employed  in 
exterior  wall  construction,  either  for  ornamental  portions  only, 
or  even  for  entire  facades.  Where  a  combination  of  brick  and 
terra-cotta  is  used,  the  latter  material  is  generally  employed  for 
belt  courses,  friezes,  sills,  lintels  and  jambs  in  the  main  wall 
surfaces,  and  very  often  for  cornices,  pediments,  or  balconies 
which  project  beyond  the  building  lines. 

It  has  been  shown  in  Chapter  VII  (see  page  227)  that  the  be- 
havior of  ornamental  terra-cotta  in  both  the  Baltimore  and  San 
Francisco  conflagrations  was  decidedly  disappointing,  due  prin- 
cipally to  its  improper  use.  Heretofore,  ornamental  terra-cotta 
has  largely  been  used,  in  both  design  and  construction,  as  a 
mere  ornamental  covering  for  steel  members,  or,  conversely,  its 
manufacture  and  use  have  both  been  such  as  generally  to  require 
interior  steel  supporting  members  for  many  of  those  features  of 
wall  construction  commonly  made  of  terra-cotta,  thus  ignoring 
its  self-sustaining  qualities,  if  rightly  made  and  used.  Thus, 
sills,  lintels,  mullions  and  cornices,  when  made  of  ornamental 
terra-cotta,  are,  in  a  great  majority  of  cases,  absolutely  dependent 
for  support  upon  spandrel  or  wall  members  of  steel,  which,  owing 
to  inadequate  thickness  and  jointing  of  the  masonry,  expand 
with  disastrous  results  to  their  coverings.  Such  failures  of 
terra-cotta  are  more  fully  discussed  in  the  later  paragraphs 
" Spandrels,"  "Mullions,"  and  "Cornices." 

From  a  fire-protection  viewpoint,  therefore,  ornamental  terra- 
cotta should  be  made  heavier,  say  1|  inches  to  2  inches  minimum 
thickness,  so  that  it  may  carry  both  its  own  weight  and  its  share 
of  the  wall  load. 


638         FIRE    PREVENTION    AND    FIRE    PROTECTION 

That  the  material  may  be  manufactured  strong  enough  to 
permit  of  such  use,  is  shown  by  the  following  data  as  to  the 
strength  of  ornamental  terra-cotta,  given  by  Mr.  Kidder  in  his 
"Architects'  and  Builders'  Pocket  Book."* 


Crushing 
weight  per 
cubic  inch. 

Crushing 
weight  per 
cubic  foot. 

Terra-cotta  block, 

2-inch  square, 

red  ,....• 

Lbs. 

6840 

Tons. 
492 

Terra-cotta  block, 
Terra-cotta  block, 

2-inch  square, 
2-inch  square, 

buff  
gray  

6236 
5126 

449 
369 

From  these  results,  the  writer  would  place  the  safe  work- 
ing strength  of  terra-cotta  blocks  in  the  wall  at  5  tons  per  square 
foot  when  unfilled,  and  10  tons  per  square  foot  when  filled  solid 
with  brickwork  or  concrete. 

A  cornice  modillion  made  by  the  Northwestern  Terra- 
Cotta  Company,  11J  inches  high  at  the  wall  line,  8  inches  wide 
on  face,  with  a  projection  of  2  feet,  was  built  into  a  wall  and  the 
upper  surface  loaded  with  pig  iron  to  the  extent  of  two  tons 
without  effect. 

The  blocks  should  invariably  be  backed  up  with  brick  masonry, 
and  in  all  .possible  cases  the  hollow  faces  in  the  rear  of  the  blocks 
should  be  well  filled  with  mortar,  into  which  bricks  or  parts  of 
bricks  should  be  worked  to  make  the  masonry  as  solid  as  possible. 
The  brick  backing  should  be  anchored  to  the  steel  frame,  either 
by  hooking  rods  or  anchors  over  portions  of  the  frame,  or  by 
passing  anchors  through  holes  punched  in  the  frame  for  that  pur- 
pose. In  many  constructions  the  individual  terra-cotta  blocks 
must  be  anchored  to  the  brick  backing  or  to  the  steel  frame  direct. 
The  terra-cotta  is  usually  built  up  in  advance  of  the  backing,  one 
course  at  a  time.  Usual  examples  of  fastening  the  terra-cotta 
and  backing  are  given  in  following  paragraphs  describing  "  Span- 
drels" and  " Cornices,"  etc. 

After  setting,  the  joints  should  be  raked  out  to  a  depth  of 
1  inch  and  pointed  with  Portland  cement,  colored  to  suit  the 
shade  of  terra-cotta  employed. 

Structural  Terra-cotta  Walls  are  built  of  two  distinct  types, 
—  those  without  other  surface  finish,  and  those  intended  to 
receive  a  finishing  surface  of  some  other  material. 

*  Page  230,  1909  Edition. 


WALL    CONSTRUCTION 


639 


For  the  former  type,  the  material  must  be  dense  enough  or  so 
glazed  as  to  be  impervious  to  moisture,  hence  the  tile  used  are 
either  —  (a)  dense  or  hard-burned,  (b)  salt-glazed  vitrified,  or 
(c)  a  combination  of  these  two. 

That  tile  walls  of  this  character  may  carry  very  considerable 
loads  is  shown  by  tests  made  by  Prof.  Woolson  (1907)  on  ten 
blocks  of  the  dense,  vitrified  type  manufactured  by  the  National 
Fire  Proofing  Company.  Each  block  was  8  inches  by  16  inches 
in  bed  area,  8  inches  high,  smooth  on  all  faces,  webs  about  lj 
inches  thick,  with  two  holes.  The  average  maximum  load  on 
each  block  was  346,171  pounds,  or  an  average  load  per  square 
inch  of  material  of  5820  pounds. 

Finished  tile  walls  may  often  be  used  to  advantage,  either 
load-bearing,  for  moderate  heights  and  loads,  or  as  veneer  walls, 
carried  on  steelwork. 

An  example  of  the  former  use  is  illustrated  in  the  Amelia 
Apartments,  Akron,  Ohio,  Charles  Henry  &  Son,  architects. 


f 


r 


:G.  252.  —  Detail  of  Hollow  Tile  Exterior  Walls,  Amelia  Apartments, 
Akron,  Ohio. 


This  five-story  and  basement  building  *  was  constructed  through- 
out of  hard-burned  vitrified  tile.  The  exterior  walls  were  made 
of  outer  8-inch  and  inner  4-inch  tile,  the  outer  being  laid  up  in 
regular  courses  6  inches  deep,  with  alternate  header  and  stretcher 
courses,  forming  a  "Flemish"  bond  (see  Fig.  252).  The  box 


*  See  Fireproof  Magazine,  July,  1903. 


640 


FIRE   PREVENTION   AND   FIRE    PROTECTION 


frames  at  all  openings  were  recessed  into  specially  formed  jamb 
tile,  while  the  belt  courses  at  each  story  at  window  levels  acted 
also  as  window  sills,  both  as  shown 
in  Fig.  253. 

An  example  of  tile  veneer  con- 
struction walls  is  the  Wisconsin 
Central  Railway  Company's  freight 
house  at  Chicago,  wherein  a  combi- 
nation of  dense  and  salt-glazed  tile 
was  used,  carried  on  steel  girders, 
and  surrounding  steel  columns.  For 
details  of  same  see  Fireproof  Maga- 
zine, August,  1903. 

Tile  walls  as  described  above  are 
only  suitable  for  use  in  buildings 
which  contain  no  great  amount  of 
combustible  material,  or  which  pre- 
sent no  severe  exposure  hazard.  It 
has  been  pointed  out  in  Chapter  VII 
FIG.  253. -Detail  of  Window  that  hard-burned  tile  is  particularly 

Jambs     and     Sills,     Amelia  ,  .,  ,     ,  ,       ^ 

Apartments,  Akron,  Ohio.  susceptible  to  damage  by  fire,  and  at 
least  two  well-known  fires  have 

demonstrated  the  truth  of  this  statement  as  applied  to 
wall  construction.  The  first  was  the  Schiller  Theater  fire  in 
Chicago,  where  a  6-inch  vitrified  tile  wall  was  seriously  damaged 
by  the  burning  of  an  ordinary  construction  building,  distant  30 
feet.  The  second  was  the  burning  of  the  Detroit  Opera  House, 
1897,  which  destroyed  large  portions  of  the  hard-tile  walls  of  the 
adjoining  ten-story  Leonard  Building. 

For  the  second  type  of  tile  wall-construction,  viz.,  tile  to  be 
finished  by  some  other  material,  ordinary  porous  or  semi-porous 
stock  may  be  used,  finished  with  plaster,  pebble-dash,  etc. 

Tests  made  by  Professor  Woolson  on  semi-porous  blocks  made 
by  the  National  Fire  Proofing  Company,  8  inches  by  12  inches 
in  bed  area,  12  inches  high,  6  holes,  webs  about  f  inch  thick,  sides 
scored  to  receive  plaster  or  stucco,  showed  the  average  maximum 
load  on  each  block  to  be  137,700  pounds,  or  an  average  of  3292 
pounds  per  square  inch  of  material  tested.  From  these  tests  the 
National  Fire  Proofing  Company  has  prepared  the  following  table 
of  ultimate  loads  for  varying  thicknesses  of  semi-porous  tile 
walls : 


WALL    CONSTRUCTION 


641 


ULTIMATE  LOAD  IN  POUNDS  PER  LINEAL  FOOT  OF  WALL  — 
TILE   SET   WITH  WEBS   VERTICAL. 


Size  of  tile. 

Width  of 
wall  1  tile 
thick. 

Ultimate  load 
per  lineal  foot 
of  wall,  pounds. 

Width  of  wall 
2  tiles  thick. 

Ultimate  load 
per  lineal  foot 
of  wall,  pounds. 

Inches. 

Inches. 

Inches. 

4X12X12 

4 

79,008 

8 

158,016 

5X12X12 

5 

85,592 

10 

171,184 

6X12X12 

6 

102,052 

12 

204,104 

7X12X12 

7 

108,636 

14 

217,272 

8X12X12 

8 

121,804 

16 

243,608 

A  well-known  example  of  the  use  of  such  walls  is  in  the  Marl- 
borough-Blenheim  Hotel  Annex,  Atlantic  City,  N.  J.,  where  the 
walls  for  all  stories,  save  the  first,  are  of  hollow  tile,  carried  on 
concrete  girders  at  the  floor  levels.  The  inner  and  outer  surfaces 
of  the  tile  are  scored  to  receive  the  inside  plaster  and  an  outside 
finish  of  a  pebble-dash  coat  of  1  :  1  cement  mortar. 

Further  information  regarding  terra-cotta  wall  construction, 
particularly  as  applied  to  residences,  is  given  in  Chapter  XXIV. 

Concrete  Walls  may  be  made  solid,  of  a  single  thickness,  or 
double,  with  air-space  between.  Both  constructions  possess 
superior  fire-resisting  qualities,  and  both  are  cheaper  than  equiva- 
lent walls  of  brick  masonry. 

Solid  Concrete  Walls  are  more  commonly  used  than  hollow 
walls,  and  when  properly  built  of  a  thickness  not  less  than  6 
inches,  will  generally  prove  sufficiently  impervious  to  moisture 
to  warrant  their  use  in  factories,  etc. 

In  walls  6  inches  thick  or  under,  small  vertical  reinforcing  rods, 
about  |-inch  diameter,  are  usually  placed  18  to  24  inches  centers. 
This  is  to  increase  the  strength,  and  particularly  to  reinforce  the 
construction  during  pouring  and  setting.  A  6-inch  solid  concrete 
wall  is  cheaper  than  an  8-inch  brick  wall,  and  usually  cheaper 
than  a  4-inch  concrete  wall,  owing  to  the  greater  ease  of  pouring 
the  concrete  and  placing  the  reinforcing  steel  in  position. 

If  Portland  cement  concrete  could  be  laid  in  thin  walls  as 
cheaply  as  in  mass  work  it  would  be  one  of  the  most  inexpensive 
materials  for  permanent  construction.  As  a  matter  of  fact,  an 
experienced  contractor  can  build  a  6-inch  wall  of  concrete  which 
will  be  stronger,  more  durable,  and  no  more  expensive  than  a 
12-inch  wall  of  brick.  The  chief  cost  in  concrete  wall  construe- 


642         FIRE    PREVENTION    AND    FIRE    PROTECTION 

tion  is  in  the  labor  of  building  and  raising  the  forms  and  of  hoist- 
ing the  concrete.* 

In  factories,  etc.,  the  walls  are  sometimes  carried  up  with  the 
columns,  but  more  frequently,  especially  where  large  window 
areas  occur,  it  is  more  economical  to  fill  in  the  wall  panels  after 
the  columns  and  spandrels  are  completed,  in  which  case  the  walls 
become  " curtain"  walls,  as  described  in  a  later  paragraph. 
Slots  in  the  columns  for  bonding  in  the  curtain  walls  may  be  se- 
cured by  nailing  rebate  strips  on  the  inside  of  the  column  forms. 

Hollow  Concrete  Walls  possess  greater  stability  than  solid  walls, 
and  the  air-space  makes  the  penetration  of  moisture  less  likely, 
especially  under  extreme  temperatures.  Hollow  walls  are  usually 
made  3  inches  to  4  inches  thick  in  each  face,  3  inches  to  3i  inches 
being  a  minimum  thickness  at  which  such  concrete  work  can 
well  be  placed.  The  cheapest  method  of  obtaining  an  air-space 
is  by  building  in  a  central  course  of  hollow-tile  blocks. 

Concrete-block  Walls,  f  —  Concrete  building  blocks  are  so 
inferior  in  respect  to  strength,  stability,  permeability  and  fire- 
resistance,  that  it  is  difficult  to  see  wherein  their  use  should  be 
encouraged.  Greatly  superior  constructions  may  be  had  at  only 
slightly  increased  cost.  Many  building  laws  prohibit  their  use 
entirely,  or  else  restrict  their  employment  to  buildings  of  stated 
occupancy  or  limited  height. 

For  ordinary  buildings,  average  practice  requires  walls  of 
concrete-block  construction  to  be  of  thicknesses  as  follows: 

One-story  buildings,  8-inch  walls. 

Two-story  buildings,  10-inch  walls. 

Three-story  buildings,  12-inch  and  10-inch  walls. 

Four-story  buildings,  15-inch,  12-inch  and  10-inch  walls. 

Combination  Tile  and  Concrete  Walls,  as  particularly 
applicable  to  residences  and  similar  buildings,  are  described  in 
Chapter  XXIV  (see  particularly  page  780).  • 

Thickness  of  Walls.  —  The  thickness  of  walls  for  fire-re- 
sisting buildings  will  be  largely  governed  by  the  local  building 
ordinance  in  force,  at  least  in  so  far  as  their  load-bearing  capacity 
is  concerned;  but  over  and  above  such  requirements,  it  should 
be  borne  in  mind  that  adequate  fire-resisting  walls  for  severe 
conditions,  at  least,  will  generally  require  greater  thicknesses  than 
may  be  demanded  by  their  bearing  functions  alone.  Again, 

*  Taylor  and  Thompson's  "Treatise  on  Concrete,  Plain  and  Reinforced." 
t  See  also,  paragraph  "Concrete  Residences,"  Chapter  XXIV,  page  776. 


WALL    CONSTRUCTION  643 

experience  has  shown  that  thick  walls  are  far  more  reliable  under 
fire  test  than  thin  walls.  These  facts  are  often  overlooked. 
Cognizance  should,  therefore,  be  taken  of  the  particular  condi- 
tions existing  as  to  internal  hazard  and  external  exposure. 

It  is  the  generally  accepted  opinion  that  a  12-inch  brick 
wall  will  prevent  the  passage  of  fire,  but  a  much  thicker  wall  may 
fail  to  confine  the  heat  of  a  burning  building  sufficiently  to  pre- 
vent the  ignition  of  combustible  merchandise  or  other  material 
in  an  adjoining  building.  In  a  fire  which  occurred  in  Boston, 
several  years  ago,  combustible  material  was  ignited  through  a 
3-foot  wall  which  became  so  hot  as  to  conduct  the  heat  into 
the  adjoining  building.  In  an  isolated  location  an  owner  might 
be  permitted  to  construct  his  walls  with  reference  only  to  their 
carrying  capacity,  but  when  he  builds  in  the  compact  part  of  a 
city,  storing  combustible  materials  from  cellar  to  roof,  he  should 
be  required  so  to  build  that  a  fire  in  his  premises  will  not  neces- 
sarily destroy  his  neighbor's  property.* 

The  following  thicknesses  of  walls  recommended  by  the  Na- 
tional Fire  Protection  Association  may  be  used  as  conservative 
practice  for  ordinary  conditions. 

Brick  Bearing  Walls>  when  carrying  floors,  to  be  of  good,  hard- 
burned  brick  laid  in  best  of  cement  mortar  with  joints  flushed  full. 
To  be  not  less  than  16  inches  thick  for  the  upper  two  stories, 
increasing  in  thickness  4  inches  for  each  three  stories  below  or 
fraction  thereof  (or  to  be  of  an  equivalent  average  thickness). 
If  walls  are  over  100  feet  long,  they  shall  be  4  inches  thicker 
than  the  above,  or  they  shall  be  strengthened  by  piers  or  pilasters 
placed  not  over  20  feet  apart. 

Exterior,  Non-bearing  Walls.  —  Self-supporting  walls  carried 
up  solidly  from  the  foundation  to  be  not  less  than  12  inches  thick 
for  the  upper  three  stories,  16  inches  thick  for  the  next  three 
lower  stories,  and  20  inches  thick  for  the  stories  below,  all  to  be 
well  anchored  to  the  steel  frame.  If  walls  are  over  100  feet  long, 
they  shall  be  4  inches  thicker  than  above,  or  they  shall  be  strength- 
ened by  piers  or  pilasters  located  not  over  20  feet  apart. 

Veneer  Walls,  if  carried  on  the  steel  frame,  must  be  of  brick 
not  less  than  12  inches  thick  in  any  portion.  This  in  addition 
to  ornamental  facings  or  other  materials,  if  any. 

"Fire  Division"  Walls.  —  Each  steel  frame  and  wall  to  be 
independent  from  that  of  adjoining  section  or  building,  irre- 

*  "  How  to  build  Fireproof  and  Slow-burning,"  by  F.  C.  Moore. 


644         FIRE    PREVENTION    AND    FIRE    PROTECTION 

spective  of  the  type  of  construction  of  the  adjoining  structure. 
Each  of  the  walls  so  adjoining  to  be  not  less  than  12  inches  thick. 

Self-supporting  or  bearing  walls  to  be  not  less  than  16  inches 
thick  for  the  upper  two  stories,  increasing  in  thickness  4  inches 
for  each  three  stories  below,  or  fraction  thereof  (or  to  be  of  an 
equivalent  average  thickness).  ^ 

The  unreliability  of  stone  masonry  under  fire  test  is  recognized 
by  the  Boston  Building  Law  which  requires  that  "in  reckoning 
the  thickness  of  walls,  ashlar  shall  not  be  included  unless  the 
walls  are  at  least  16  inches  thick  and  the  ashlar  is  at  least  8  inches 
thick,  or  unless  alternate  courses  are  at  least  4  and  8  inches  to 
allow  bonding  with  the  backing." 

Anchorage*  —  The  experience  gained  in  past  fires  shows  that 
adequate  anchorage  will  often  prevent  much  fire  damage,  both 
in  preserving  the  integrity  of  the  structure  against  falling  debris, 
hot-air  explosions,  etc.,  and  in  minimizing  the  fire  loss  to  indi- 
vidual features  of  construction.  Many  fires  show  that  the 
necessity  for  proper  anchorage  has  not  been  fully  realized. 

All  main  structural  portions  of  a  building  should  be  well  tied 
together.  Beams,  girders  and  trusses,  etc.,  should  be  thoroughly 
anchored  to  the  masonry  walls,  and  in  addition,  load-supporting 
and  self-supporting  walls  should  be  provided  with  L-shaped 
corner  irons  at  all  wall  angles  or  corners. 

All  walls  of  a  first-  or  second-class  building  meeting  at  an 
angle  shall  be  securely  bonded,  or  shall  be  united  every  5  feet  of 
their  height  by  anchors  made  of  at  least  2-inch  by  ^-inch  steel  or 
iron,  well  painted,  and  securely  built  into  the  side  or  partition 
walls  not  less  than  36  inches,  and  into  the  front  and  rear  walls 
at  least  one-half  the  thickness  of  such  walls.* 

The  anchorage  of  veneer  walls  is  especially  important,  as  is 
pointed  out  later  in  paragraph  "  Spandrels." 

The  necessity  for  anchorage  of  ornamental  terra-cotta  has 
previously  been  mentioned,  and  numerous  examples  are  given 
in  later  paragraphs  concerning  "Spandrels,"  "Lintels,"  "Mul- 
lions  "  and  "Cornices." 

Stone  facings  should  also  be  anchored  to  the  brick  backing, 
preferably  by  means  of  galvanized-iron  flat  or  round  anchors. 

In  brick  walls  the  use  of  light  metal  clips  or  anchors  to  tie 
face  brick  to  the  backing  should  be  prohibited.  Such  anchors 
failed  utterly  in  the  case  of  the  Continental  Trust  Company's 

*  Boston  Building  Law. 


WALL   CONSTRUCTION  645 

Building  in  the  Baltimore  fire,  where  large  sections  of  the  four- 
inch  pressed-brick  facings  of  the  side  and  rear  walls  fell  off.  The 
same  cause  of  failure  in  face  brick  was  seen  in  the  San  Francisco 
fire.  Also,  in  the  Equitable  Building  in  Baltimore,  the  infre- 
quent bonding  of  corner  bricks  in  the  light  court  failed  to  hold 
the  face  brick  in  position. 

Hence,  all  brick  walls  should  be  well  bonded  with  full  brick 
headers.  This  will  increase  the  strength  and  stability  of  brick 
walls  of  whatever  nature,  and,  in  the  case  of  faced  walls,  will 
insure  a  minimum  damage  to  the  facing. 

Wherever  brick  was  used  for  the  fagades,  the  bonding  was 
seldom  carefully  done.  Sometimes  metal  clips  were  depended 
upon  solely  for  this  purpose.  In  most  cases  every  sixth  to  eighth 
course  was  bonded  to  the  backing.  There  were  numerous  in- 
stances where  the  bond  of  the  face  brick  was  broken  and  they 
were  precipitated  to  the  ground.  In  future  work  this  detail 
should  be  carefully  attended  td~and  at  least  every  third  or  fourth 
course  should  be  bonded  to  the  backing.* 

Openings  in  Walls.  —  All  openings  in  exterior  walls  should 
be  provided  with  efficient  fire  doors,  windows,  or  shutters  as 
described  in  Chapter  XIV.  This  rule  applies  to  all  openings, 
and  not  to  doors  or  windows  only.  It  is  the  careful  attention  to 
minor  means  of  communication  that  often  insures  protection  in 
case  of  emergency.  Openings  left  for  the  passage  of  pipes,  flues,  . 
belts  or  shafting,  etc.,  should  receive  an  equal  consideration 
with  doors  or  windows. 

Shaft  Openings.  —  Fig.  254  shows  a  fire-resisting  casing  for  a 
shaft  opening  in  a  fire  wall,  as  recommended  by  the  Boston  Board 
of  Fire  Underwriters.  The  flap  doors  should  be  made  in  ac- 
cordance with  the  specifications  for  tin-clad  fire  doors  and  shutters 
given  in  Chapter  XIV. 

Belt  Openings,  in  fire  walls,  should  be  protected  by  means  of 
sliding  doors  as  required  by  the  National  Board  rules  (see  Fig. 
255). 

(a)  To  be    made    of  two    thicknesses    of  yj-inch   boards. 
Otherwise  follow  specifications  for  Tin-clad  Fire  Doors. 

(b)  To  be  provided  with  two   suitable  hooks  and   staples 
for  holding  doors  closed. 

(c)  To  slide  in  upper  and  lower  guard  rails  or  channels  re- 
taining the  doors  in  place.     Channels  to  be  made  of  2£  by  2 \  by 

*  See  "The  San  Francisco  Earthquake  and  Fire,"  by  A.  L.  A.  Himmel- 
wright. 


646         FIRE    PREVENTION    AND    FIRE    PROTECTION 


FIG.  254.  —  Standard  Cut-off  for  Shaft  Opening  between  Buildings. 


FIG.  255.  —  Standard  Doors  for  Belt  Openings. 


WALL   CONSTRUCTION  647 

^-inch  angle  irons  securely  riveted  together  and  secured  by  J-inch 
bolts  through  the  wall.  Z-bars  of  proper  dimensions  may  be 
used  if  obtainable.  Channels  to  be  long  enough  to  retain  doors 
when  open. 

(d)  A  metal  hood  may  be  used  if  securely  fastened  to  the 
wall.  Hoods  should  be  constructed  of  heavy  galvanized-iron, 
without  the  use  of  solder. 

Metal  hoods  are  inferior  to  the  double  doors  and  should 
be  used  only  when  the  doors  are  not  practicable. 

Furring  of  Exterior  Walls.  —  If  the  exterior  walls  are  to  be 
finished  on  the  inside,  plastering  is  sometimes  applied  directly 
on  the  masonry,  but  if  it  is  desired  to  insulate  the  walls  against 
the  passage  of  dampness,  heat,  cold  or  sound,  some  form  of 
furring  is  employed  so  as  to  produce  an  air-space  between  the 
masonry  and  the  plaster.  In  refrigerator  and  cold-storage  build- 
ings and  in  breweries,  furring  is  employed  to  preserve  a  uniform 
temperature.  In  churches  and  theaters,  furring  is  often  used 
for  acoustic  properties,  while  in  dwellings,  stores  and  mercantile 
buildings,  it  is  generally  used  to  prevent  the  penetration  of  damp- 
ness, and  to  exclude  cold  in  winter  and  heat  in  summer.  From 
the  standpoint  of  fire-resistance,  the  furring  of  exterior  walls  by 
means  of  tile  or  hollow  brick  is  decidedly  advisable  in  storage  or 
mercantile  buildings  containing  large  quantities  of  combustible 
merchandise. 

Such  furrings  may  be  made  of  hollow  brick,  terra-cotta  tile, 
metal  studding  and  lathing,  or  gypsum  blocks,  and  their  relative 
value  as  regards  fire-resistance  will  be  in  about  the  order  named. 
Wood  furring  or  lathing  should  never  be  employed. 

Hollow  bricks  constitute  the  most  efficient  form  of  fire-resisting 
wall  furring.  They  are  largely  used  in  warehouses,  mercantile 
buildings  and  the  like,  where  the  walls  are  16  inches  thick  or 
more.  The  New  York  Building  Law  allows  the  inclusion  of 
hollow  bricks  in  determining  wall  thicknesses.  For  walls  less  than 
16  inches  thick  they  may  be  used  for  south  or  court  walls,  but 
not  for  walls  exposed  to  driving  rain  storms. 

Hollow  brick  (also  called  "  Havers traw"  hollow  brick)  are 
commonly  made  of  the  same  material  and  size  as  ordinary  brick, 
except  that  voids,  usually  two,  run  from  end  to  end.  They 
should  be  built  up  with  and  bonded  into  the  body  of  the  wall  by 
means  of  headers,  which,  by  some  manufacturers,  are  made  with 
four  voids  running  from  side  to  side  of  the  bricks.  Hollow  bricks 
are  sometimes  " scored"  or  grooved  on  the  faces  to  receive  the 


648 


FIRE    PREVENTION    AND    FIRE    PROTECTION 


plastering.     The    standard    sizes    and    weights    made    by    the 
National  Fire  Proofing  Company  are  as  follows: 
Stretcher,  2J  by  3i  by  8  inches.     Weight,  3  pounds. 
Header,  2|  by  3J  by  7J  inches.     Weight,  2|  pounds. 
Porous  stretcher,  2j  by  3}  by  8  inches.     Weight,  2J  pounds. 
Solid  porous  stretcher,  2J  by  3  J  by  8  inches.   Weight  3J  pounds. 
The  porous  stretchers  are  employed  where  nails  must  be  used 
to  secure  trim,  etc. 

Terra-cotta  Wall  Furring  is  made  of  dense,  semi-porous  or 
porous  terra-cotta  blocks  of  the  form  shown  in  Fig.  256.  The 
blocks  are  made  either  li  or  2  inches  thick  and  12  inches  square. 
They  should  be  set  with  the  ribs  vertical  and  be  fastened  to  the 

wall  by  driving  tenpenny  nails  in 
the  joints  of  the  brickwork,  the 
head  of  the  nail  being  bent  down 
upon  the  tile,  using  a  nail  over 
every  third  block  in  every  second 
course.  The  blocks  should  not 
be  bedded  in  mortar  at  the  back 
since  this  would  defeat  their 
purpose  by  making  a  solid  con- 
nection to  carry  the  moisture 
through. 

Where  walls  must  be  straight- 
ened or  furred  out  to  line  with 
the  face  of  piers,  the  2-inch  blocks  cannot  be  used.  If  the  ceiling 
height  is  not  too  great,  use  3-inch  partition  blocks.  If  the  space 
is  greater  than  3  inches  the  blocks  may  be  set  out  from  the  wall 
leaving  a  clear  air-space  behind  them.  They  should  be  braced 
at  intervals  by  the  use  of  drive  anchors,  or  4-inch  blocks  may  be 
used  without  the  anchors. 

The  face  of  the  blocks  is  grooved  to  receive  the  plastering. 
The  12  by  12  by  IJ-inch  blocks  weigh  9  pounds  per  square  foot, 
and  the  12  by  12  by  2-inch  blocks  weigh  10  pounds  per  square 
foot. 

Metal  Furring  and  Lathing  for  exterior  walls  is  extensively  em- 
ployed, but  such  constructions  are  more  effective  as  insulators 
against  dampness,  heat  and  cold,  than  against  direct  attack  by 
fire  and  water.  The  furring  consists  of  some  light  metal  mem- 
bers which  are  attached  to  the  masonry  —  angles,  channels 
or  sheet-iron  studs,  to  which  wire  or  metal  lathing  is  wired. 


FIG.   256.  —  Terra-cotta  Wall  Fur- 
ring. 


WALL   CONSTRUCTION  649 

Wire  lathing  with  1-inch  V-shaped  ribs  woven  in  every  7J  inches 
is  sometimes  used. 

Gypsum  Blocks  are  also  used  as  wall  furring,  but,  while  ex- 
cellent as  far  as  the  non-conductivity  of  heat  is  concerned,  are 
open  to  the  same  objections  as  are  the  gypsum  partition  blocks 
described  on  page  393.  For  stories  of  ordinary  height,  blocks 
1|  inches  or  2  inches  thick  with  ribbed  backs  (as  shown  in  Fig. 
256)  are  used,  or  solid  blocks  1|  inches  thick.  These  are  laid 
with  a  J-inch  air-space  between  the  blocks  and  the  wall,  as  the 
blocks  would  otherwise  absorb  any  moisture  which  might  pene- 
trate the  wall.  The  blocks  are  fastened  to  the  masonry  by  means 
of  nails  driven  through  the  blocks  into  the  joints  of  the  brick  or 
stonework.  If  a  wider  air-space  is  required,  thus  making  the 
furring  blocks  virtually  free-standing,  partition  blocks  are  used. 

Concrete  Walls.  —  If  concrete  walls  are  to  be  furred,  provision 
must  be  made  for  the  attachment  of  the  furring  when  the  walls 
are  building.  This  can  best  be  accomplished  by  means  of  the 
"Rutty  Non-furring  Nailing  Plugs,"  which  consist  of  doubled 
or  two-thickness  sheet-iron  plugs  which  are  built  into  the  wall 
with  the  outer  ends  projecting  out  between  the  joints  of  the  wood 
forms.  Wire  or  metal  lathing  is  then  attached  to  the  free- 
standing ends  of  the  plugs  by  means  of  nails  or  staples  which 
are  driven  in  between  the  two  closely  fitting  sheets  of  each 
plug. 

Cold-storage  Insulation.  —  An  efficient  fire-resisting  insulation 
for  brick  walls  in  cold-storage  warehouses,  refrigerating  plants, 
etc.,  consists  of  2  coats  of  pitch  on  inside  of  brick  wall,  2-inch 
hollow-tile  furring,  4  inches  of  mineral  wool,  3-inch  hollow-tile 
furring,  finished  with  an  inside  coat  of  cement  plaster. 

Wall  Finishes.  —  There  is  undoubtedly  a  great  field  for  im- 
provement in  the  matter  of  providing  some  indestructible  or 
practically  indestructible  finish  for  the  exterior  surfaces  of  walls. 
The  great  damage  done  to  stone,  ornamental  terra-cotta,  and 
even  to  face  brick  under  severe  fire  test  has  previously  been 
pointed  out.  The  best  that  can  be  done  under  present  methods 
is  either  to  use  such  finished  materials  as  will  inevitably  suffer 
damage,  but  to  use  them  in  such  mass,  solidity  and  quality,  and 
in  such  manner,  as  to  make  the  resultant  damage  by  fire  as  little 
as  possible;  or  to  use  common  brick  or  concrete,  to  which  can 
be  applied  a  finish  of  the  nature  of  stucco,  the  destruction  of 
which  by  fire  is  to  be  expected,  but  the  renewal  of  which  will  not 


650         FIRE    PREVENTION    AND    FIRE    PROTECTION 

be  expensive  —  as  suggested  by  Captain  Sewell  (see  Chapter  VI, 
page  205). 

Plaster  and  stucco  wall  finishes  are  considered  at  more  length 
in  Chapter  XXIV. 

The  exposed  surfaces  of  concrete  walls  are  variously  treated 
in  attempts  to  produce  a  satisfactory  appearance.  Where  no 
special  provision  is  made,  the  marks  of  the  lumber  used  in  the 
forms  are  almost  certain  to  show,  and  the  lines  of  demarcation 
between  successive  layers  are  clearly  defined.  To  eliminate  these 
lines,  grooves  are  sometimes  purposely  formed,  by  tacking  on 
the  sides  of  the  moulds  triangular  or  trapezoidal  strips  that  pro- 
duce sunk  joints  in  the  wall,  giving  it  an  appearance  resembling 
dressed  stone.  The  successive  layers  of  concrete  are,  in  such 
cases,  stopped  at  these  lines  so  that  the  junction  of  the  two  layers 
is  hidden. 

In  some  cases  the  surface  is  purposely  left  rough  and 
scratched  like  a  scratch  coat  in  plastering,  and  then  stuccoed 
with  a  neat  cement  or  a  rich  cement  mortar.  In  this  form  of 
finish  there  is  always  some  danger  of  the  stucco  flaking  off. 

The  surface,  as  it  comes  from  the  mould,  is  sometimes 
hammer-dressed,  or  rather  picked  with  a  special  hammer. 

Another  method  sometimes  employed  is  to  remove  the 
forms  as  soon  as  the  concrete  is  sufficiently  hard,  and  to  rub  the 
surface  with  a  plasterer's  float,  using  fine  sand  between  the  float 
and  the  wall  surface,  and  plenty  of  water.* 

See  also  "A  Surface  Finish  for  Concrete,"  illustrated,  by 
Henry  H.  Quimby,  Engineering  News,  Dec.  20,  1906. 

The  pointing  of  stone  or  brick  masonry  should  always  be  with 
concave  joints.  The  convex  pointing  of  joints  will  invariably 
break  off  under  fire. 

Spandrels.  —  Spandrels  constitute  those  portions  of  the  ex- 
terior walls  which  lie  between  the  piers  and  between  the  window 
openings  of  the  successive  stories. 

In  load-supporting  or  self-supporting  walls,  these  portions 
present  no  especial  difficulty,  as  they  are  easily  cared  for  by  in- 
troducing lintel  beams,  channels,  angles  or  tees,  which  rest 
directly  upon  the  masonry  piers;  or  the  support  is  made  through 
the  use  of  stone  lintels,  or  by  the  arching  of  the  masonry  over 
the  openings. 

In  veneer-  or  skeleton-construction,  however,  considerable 
ingenuity  is  often  required  to  carry  the  construction  properly. 
The  spandrels  are  often  made  thinner  than  the  piers  surrounding 

*  Rudolph  P.  Miller,  in  Kidder'a  "Architects'  and  Builders'  Pocket-Book. 


WALL    CONSTRUCTION  651 

the  exterior  columns,  in  order  to  reduce  the  loads  on  the  spandrel 
beams,  as  well  as  to  throw  the  spandrels  "in  reveal,"  thus  accen- 
tuating the  piers  for  architectural  effect.  In  this  construction 
the  support  of  the  brickwork  and  fireprbofing,  and  the  proper 
attachment  of  ornamental  terra-cotta,  if  used,  bring  up  many 
problems  calling  for  originality  and  practical  adaptability. 

The  methods  employed  can  be  best  described  by  means  of 
illustrations.  Quite  a  number  of  examples  are  given  in  the 
author's  "  Architectural  Engineering/'  with  descriptions  of  the 
ordinary  methods  employed  in  skeleton-construction  buildings. 
A  few  examples  only  will  be  here  pointed  out,  referring  especially 
to  fire-resisting  considerations. 

Requirements.  —  Before  examining  typical  spandrel  details  as 
customarily  made,  it  will  be  well  to  consider  the  requirements 
demanded  of  spandrel  construction  from  the  standpoint  of  fire- 
resistance.  Such  requirements,  as  demonstrated  by  past  ex- 
perience, include: 

1.  That  spandrels,  and  especially  the  lintels,  be  made  as  nearly 
self-supporting  as  possible.      To  this  end  windows  should  be 
made  of  moderate  width,  as  described  in  following  paragraph 
"Mullions,"  with  piers  of  sufficient  stability  to  take  the  lintel 
loads  or  arch  thrusts.     No  lintel  will  equal  the  brick  arch  in 
fire-resistance,  but  if  a  more  ornamental  treatment  is  desired, 
ornamental  terra-cotta  may  be  used,  but  should  be  made  self- 
supporting  for  the  arch  or  lintel  portion  at  least.     The  desir- 
ability of  changing  current  practice  in  the  use  of  ornamental 
terra-cotta  has  been  pointed  out  in  Chapter  VII,  and  also  earlier 
in  this  chapter.     In  any  reasonable  design  there  should  be  no 
difficulty  in  making  terra-cotta  lintels  of  eight  or  twelve-inch 
reveals,  self-supporting. 

2.  That  steel  spandrel  or  lintel  members,  if  required  or  used, 
be  adequately  protected  against  possible  fire.     If  the  window 
widths  are  such  that  the  lintel  constructions  cannot  be  made 
self-supporting,  then  steel  spandrel  members  must  be  depended 
on,  but  such  angles,  channels,  beams  or  riveted  girders  should 
be  well  behind,  or  preferably  above,  the  lintel  construction,  and 
should  be  efficiently  protected  on  all  sides.     The  common  prac- 
tice of  relying  on  4  inches  of  hollow  ornamental  terra-cotta  blocks 
for  the  protection  of  steel  spandrel  members,  whether  on  soffit 
or  face,  is  inadequate.     Four  inches  of  well-laid  brick  may  form 
adequate  protection  against  fire,  as  is  pointed  out  later  in  dis- 


652 


FIRE    PREVENTION    AND    FIRE    PROTECTION 


cussing  wall  columns,  but  the  same  thickness  of  any  other  ma- 
terial, save  concrete,  is  certainly  insufficient. 

3.  That  the  spandrel  walls  be  made  of  such  thickness  and 
solidity  as  will  adequately  resist  the  maximum  fire  test  to  be 
expected.     Hazardous  contents  and  severe  exposure  should  be 
considered.     For  ordinary  hazards,  the  following  requirements 
of  the  National  Code  will  be  sufficient  —  based  on  a  limiting 
height  of  buildings  of  125  feet. 

Walls  of  brick  built  in  between  iron  or  steel  columns,  and 
supported  wholly  or  in  part  on  iron  or  steel  girders,  shall  be  not 
less  than  12  inches  thick  for  65  feet  of  the  uppermost  height 
thereof,  or  to  the  nearest  tier  of  beams  to  that  measurement,  in 
any  building  so  constructed;  and  the  lower  section  of  60  feet  or 
part  thereof  shall  have  a  thickness  of  16  inches. 

The  New  York  Building  Code  requires  inclosure  walls  for 
skeleton-construction  buildings  to  be  not  less  than  12  inches 
thick  for  the  uppermost  75  feet,  increasing  in  thickness  by  4 
inches  for  each  lower  section  of  60  feet. 

4.  That  the  details  of  construction  be  not  only  practicable, 
but  also  such  as  will  insure  a  minimum  damage  by  weather, 

settlement,  or  fire.  One  very  common 
defect  in  the  design  of  spandrels,  and,  in 
fact,  of  much  ornamental  terra-cotta 
work,  is  the  slotting  of  the  blocks  to 
within  two  or  three  inches  of  the  exposed 
face  to  receive  the  steel  members.  This 
is  illustrated  in  Fig.  257.  Such  practice 
is  bad  for  several  reasons.  First,  the 
effective  thickness  of  the  blocks  at  the 
edge  of  the  angle  is  reduced  to  the  face 
thickness  only.  Failure  at  this  point 
is  liable  to  occur  in  handling  during 
FIG.  257.— Spandrel  Sec-  building  operations,  or  under  fire  test. 

tion  with    Improperly    Second   the  insulation  of  the  steelwork  is 

Slotted  Lmtel  Blocks.        .  '.  -11 

insufficient,     particularly     at     the     slot. 

Third,  failure  at  this  point  is  very  liable  to  occur  under  settle- 
ment of  the  structure. 

A  far  better  detail  is  shown  in  Fig.  258. 

5.  That  thorough  anchorage  be  provided  for  all  portions  not 
self-supporting.     Methods  of  anchoring  ornamental  terra-cotta 
are  shown  in  the  following  illustrations. 


WALL    CONSTRUCTION 


653 


FIG.  258.  —  Typical  Spandrel  Section. 


Examples  of  Spandrel  Construction.  —  Fig.  259  illustrates  a 
spandrel  section  at  the  sixteenth  floor  of  the  Broadway  Chambers, 
New  York.  This  is  well  designed,  save  at  the  soffit  of  the 
window  opening  where  the  terra-cotta  lintel  blocks  are  too 


FIG.  259.  —  Spandrel  Section,  16th 
Floor,  Broadway  Chambers,  N.  Y. 


FIG.  260.  —  Spandrel  Section,  4th  Floor, 
Broadway  Chambers,  N.  Y. 


light,  and  the  double  angles  are  insecurely  protected.  Fig.  260 
shows  the  spandrel  section  at  the  fourth-floor  level  of  the  same 
building,  where  the  granite  of  the  lower  three  stories  terminates. 
The  lintel  stone  is  self-supporting. 


654 


FIRE    PREVENTION    AND    FIRE    PROTECTION 


Fig.  261*  illustrates  a  simple  and  well-designed  spandrel  sec- 
tion supported  on  a  beam  with  shelf  angle.     The  staff  bead  of 


FIG.  261.  —  Typical  Spandrel 
Section. 


FIG.  262.  —  Typical  Spandrel  Section. 


the  window  frame  is  kept  inside  the  line  of  the  terra-cotta  lintel 
blocks  to  prevent  the  breaking  of  the  latter  through  the  deflec- 
tion of  the  beam  or  settlement  of  the  building. 

Fig.  262*  shows  a  double  terra-cotta  lintel,  supported  partly 
by  shelf  bearing  and  partly  by  rod  suspension.  The  outer  angle 
is  supported  from  the  plate  girder  by  means  of  projecting  plate 
and  angle  brackets,  shown  in  dotted  lines. 


FIG.  263.  —  Typical  Spandrel  Section.  "10.  264.  — Typical  Spandrel  Section. 


Figs.  263  *  and  264  *  show  other  methods  of  supporting  terra- 
cotta lintels.  They  could  be  improved  by  making  the  soffits 
heavier,  deeper  and  self-supporting. 

*  From  typical  details  issued  by  the  Northwestern  Terra-cotta  Company. 


WALL   CONSTRUCTION 


655 


In  designing  spandrel  sections,  especial  care  should  be  given 
the  lintels,  as  the  window  soffits  almost  invariably  receive  a  more 
severe  test  by  fire  than  any  other  portions  of  the  exterior  walls. 
To  secure  the  best  results,  the  various  sections  should  be  detailed 
to  ample  scale  in  order  that  the  best  possible  arrangement  may 
be  studied  out  to  secure  a  stable  and  efficient  construction  which 
will  suffer  a  minimum  damage  from  fire  or  other  adverse  con- 
ditions. 


PLAN 

OF 

JAMB 


FIG.  265.  —  Spandrel  Section,  3rd  Floor,  Copley-Plaza  Hotel,  Boston. 

An  exceptionally  well-designed  self-supporting  spandrel  sec- 
tion, used  in  connection  with  load-supporting  exterior  walls, 
is  illustrated  in  Fig.  265.  This  is  taken  at  the  third-floor  level 
of  the  new  Copley-Plaza  Hotel,  Boston  (1911-1912),  H.  J. 
Hardenbergh,  architect. 

Court  Walls.  —  Spandrel  sections  for  court  walls  differ  in 
no  way,  as  far  as  general  principles  are  concerned,  from  those  of 
the  exterior  walls.  They  are,  however,  generally  simpler,  due 
to  the  plainer  character  of  the  wall.  A  glazed  brick  is  commonly 


656         FIRE    PREVENTION    AND    FIRE    PROTECTION 

employed  to  reflect  all  possible  light,  while  the  sill  courses  and 
lintels  are  of  terra-cotta  as  before. 

Special  Constructions,  such  as  balconies,  bay  windows,  etc., 
all  demand  individual  treatment,  depending  upon  the  design. 
The  principles  which  have  already  been  described  must  be 
adapted  to  the  conditions  to  be  met,  the  one  main  thought  from 
a  fireproofing  standpoint  being  the  complete  protection  of  the 
structural  steelwork.  A  number  of  examples  of  steel  framing 
and  spandrel  sections  for  bay  windows  are  given  in  the  author's 
11  Architectural  Engineering." 

Concrete  Spandrel  Walls.  —  For  spandrel  walls  sup- 
ported entirely  on  girders,  the  minimum  thickness  should  be 
eight  inches.  Such  walls  should  be  reinforced  with  not  less  than 
one-half  pound  of  steel  per  square  foot  of  wall,  in  the  form  of 
rods  placed  vertically  and,  less  frequently,  horizontally.* 

The  varied  tests  made  by  Professor  Woolson,  however,  show 
that  concrete  walls  less  than  8  inches  thick  would  seem  to  possess 
all  requirements  as  to  fire-resistance,  at  least  for  usual  conditions. 

I  believe  that  a  curtain  wall  4  inches  thick,  properly  made, 
will  withstand  all  any  building  may  be  expected  to  stand  in 
burning  out  the  contents  of  any  room  in  the  building  except, 
perhaps,  in  very  rare  cases.  I  have  had  buildings  in  which  the 
walls  were  never  over  3J  to  4  inches  thick,  and  have  subjected 
those  walls  to  repeated  tests  of  one  hour  each  at  a  mean  tem- 
perature of  1700  degrees,  then  applying  water  at  ordinary  pres- 
sure. Such  tests  have  not  disintegrated  the  walls,  and  we  only 
had  to  repair  them  by  plastering  in  spots  two  or  three  times.  I 
had  one  test  building  which  I  used,  I  think,  fourteen  times,  and 
when  it  was  torn  down  it  had  to  be  done  with  pickax  and  sledge. 
If  it  will  stand  punishment  of  that  sort,  I  see  no  reason  why  a 
curtain  wall  of  that  thickness  cannot  be  used  in  a  building. 

The  method  of  construction  was  very  simple.  We  used 
a  very  open  metal  construction,  with  metal  lath  as  used  for  plas- 
tering, and  the  wall  was  well  built  up  by  repeated  plasterings  of 
a  mixture  of  one  part  of  lime  containing  25  per  cent,  of  cement, 
to  aggregate  of  two  parts  sand  and  three  of  fine  cinders. f 

Mullions.  —  The  Baltimore  fire  demonstrated  conspicuously 
that  mullioned  openings,  as  commonly  built,  are  susceptible  of 
great  damage.  Windows,  especially  in  office  buildings,  are  often 
made  too  wide.  Such  openings  are  objectionable,  both  from 
the  standpoint  of  the  exposure  presented,  and  from  the  stand- 
point of  self -supporting  lintel  construction  as  before  described. 

*  Rudolph  P.  Miller,  in  Kidder's  "Architects'  and  Builders'  Pocket  Book." 
t  See  1909  Proceedings  of  National  Fire  Protection  Association,  page  167. 


WALL    CONSTRUCTION  657 

Up  to  a  certain  point,  it  costs  more  to  build  a  window  into  a 
wall  than  it  does  to  build  the  wall  solid.  There  is  a  limit,  how- 
ever, beyond  which  windows  are  cheaper  than  solid  walls.  The 
window  area  in  the  Continental  Trust  Building  was  far  beyond 
this  limit.  It  may  have  been  made  so  in  response  to  unreason- 
ing demands  for  light;  and  it  may  have  been  done  with  a  view 
to  a  low  first  cost.  In  any  event,  it  was  too  great.  The  same 
was  true  of  other  buildings.* 

If  any  consideration  is  to  be  given  to  possible  fire  damage, 
mullioned  openings  should  be  avoided,  for,  as  usually  built, 
small  mullions  of  brick,  terra-cotta  or  cast-iron  will  either  fail 
utterly  or  cause  great  damage.  If  they  are  depended  on  to 
carry  loads,  the  result  may  well  be  dangerous;  if  they  are  only 
self-supporting,  and  especially  if  made  of  cast-iron,  they  will 
probably  be  damaged  themselves  and  also  involve  the  masonry 
above  and  below. 

Spandrel  beams,  carrying  the  curtain  walls  from  story  to 
story,  failed  in  some  cases  and  allowed  a  portion  of  the  wall  to 
fall  out.  This  occurred  only  over  large  windows  and  was  partly 
due  to  strain  occasioned  by  the  expansion  of  cast-iron  window 
mullions,  which  were  fastened  to  these  spandrel  beams.  The 
lack  of  proper  protection  for  the  beams  also  contributed  largely 
to  their  failure.  Steel  members  over  window  openings  were 
commonly  provided  with  insufficient  protection  and  in  some 
cases  they  were  protected  by  the  wood  window  frames  only.  A 
severe  fire  test  of  long  duration  would,  in  all  probability,  cause 
material  damage  at  these  points. f 

If  cast-iron  mullions  are  used,  they  should  preferably  be  of 
closed  form,  and  of  substantial  thickness.  The  buckling  of 
light  U-shaped  mullions  was  conspicuous  in  the  case  of  the  Con- 
tinental Trust  Company's  Building.  If  light  terra-cotta  mul- 
lions are  employed,  with  insufficient  area  to  be  rigid  and  stable 
in  themselves,  a  metal  stiffening  member  on  the  interior  is 
advisable,  provided  the  same  be  fireproofed  before  the  surround- 
ing ornamental  terra-cotta  is  placed.  If  brickwork  is  employed, 
very  light  piers,  even  if  somewhat  larger  than  ordinary  mullions, 
should  not  be  depended  on. 

Terra-cotta  Cornices  are  designed  after  the  same  principles 
as  are  employed  in  spandrel  sections,  but  it  should  be  remembered 
that  the  original  cost  and  also  the  liability  to  excessive  fire 
damage  increase  rapidly  with  the  projection. 

*  Captain  John  Stephen  Sewell  in  his  report  on  the  Baltimore  fire  to  the 
Chief  of  Engineers,  U.  S.  A. 

t  Report  of  National  Fire  Protection  Association  on  Baltimore  fire. 


658         FIRE   PREVENTION   AND   FIRE   PROTECTION 


FIG.   266.  —  Terra-cotta  Cornice,  Wanamaker  Building,   Phila. 

From  the  standpoint  of  minimum  fire  damage,  terra-cotta 
cornices  should  be  as  plain  and  as  nearly  self-supporting  as  pos- 
sible. The  Baltimore  buildings  showed  conclusively  that  cor- 
nices of  ornamental  terra-cotta,  built  after  accepted  methods, 
will  suffer  great  fire  damage,  often  sufficient  to  necessitate  their 
entire  renewal.  This  was  especially  true  of  highly  ornamented 
or  boldly  overhanging  cornices,  and  many  of  those  which  at  first 
were  supposed  to  be  but  little  injured  had  to  be  entirely  replaced. 

In  cornices  having  any  material  overhang,  self-supporting 
construction  becomes  practically  impossible.  Hence  recourse 


FIG.  267.  —  Terra-cotta  Cornice,  Pittsburgh  Athletic  Assoc.  Building. 


WALL    CONSTRUCTION 


659 


'lagstaff 


must  be  had  to  steel  brackets,  "  outriggers  "  and  other  often  very 
elaborate  means  of  support.  In  such  cases  the  steel-supporting 
members  and  anchorage  must  all  be  designed  together,  as  the 
method  of  supporting  each  course  of  blocks  must  be  carefully 
determined,  and  holes  for  the 
anchorage,  etc.,  must  be  pro- 
vided for  in  both  the  blocks 
and  the  steel  supports,  before 
the  materials  are  fabricated. 
Such  construction  is  costly  on 
account  of  the  relatively  large 
amount  of  complicated  steel 
framing  required,  —  on  ac- 
count of  the  elaborate  forms 
of  the  terra-cotta  blocks,  usu- 
ally with  more  or  less  orna- 
mentation, —  and  on  account 
of  the  difficulties  of  setting. 
Increased  liability  to  fire 
damage  is  also  due  to  the  same 
causes,  and  to  the  fact  that 
constructions  which  overhang 
in  any  marked  degree  cannot 
be  backed  up.  The  cornice, 
therefore,  becomes  a  sham 
construction,  non-self-support- 
ing, made  up  of  many  irregu- 
larly-shaped and  highly-orna- 
mented blocks,  which,  of 
necessity,  must  be  kept  thin 
to  reduce  weight. 

Fig.     266*     illustrates     the 
cornice    of     the     Wanamaker 

Building,  Philadelphia.       This  FIG.  268.  —  Terra-cotta  Cornice,  Mayer 

is  an  extreme  example  as  to         Israel  Building-  New  Orleans, 
size  and  overhang,  and  also,  in  the  opinion  of  the  writer,  as  to 
lightness  and  susceptibility  to  fire  damage. 

Fig.  267*  illustrates  a  medium-sized  cornice  as  used  on  the 
Pittsburgh  Athletic  Association  Building,  Janssen  and  Abbott, 
architects,  and  Fig.  268  *  illustrates  the  cornice,  entablature  and 

*  For  these  details  of  cornices  the  author  is  indebted  to  the  Atlantic  Terra- 
cotta Company  who  executed  the  work, 


660         FIRE    PREVENTION   AND   FIRE   PROTECTION 

railing  on  the  Mayer  Israel  Building,  New  Orleans,  Favrot  and 
Livaudais,  architects. 

Party  Walls.  —  Party  or  dividing  walls  should  be  absolute 
barriers  against  the  spread  of  fire,  and  weak  or  thin  walls  for 
such  locations  will  be  false  economy.  In  many  cases  the  steel 
frames  for  large  and  important  structures  are  placed  directly 
against  the  walls  of  the  smaller  adjacent  buildings,  or  out  to  the 
party  lines.  In  case  of  conflagration,  the  smaller  building  will 
pull  down  its  own  wall,  and  leave  the  steelwork  of  the  newer 
structure  exposed.  The  columns  and  wall  beams  should  be 
efficiently  protected  by  their  own  wall. 

Fire  Walls.  —  See  paragraph  " Subdivision  of  Large  Areas," 
Chapter  IX,  page  305,  especially  the  limitations  of  areas  recom- 
mended by  the  National  Board  Code;  also  previous  paragraph 
"Thickness  of  Walls"  in  this  chapter. 

In  mill-construction  buildings,  or  in  any  save  those  that  are 
thoroughly  fire-resisting,  fire  walls  dividing  any  structure  into 
separate  sections  should  be  carried  from  3  to  5  feet  above  the 
roof  and  should  be  provided  with  a  durable  coping.  For  se- 
vere risks,  as  in  car  barns,  the  minimum  height  of  parapet  walls 
should  be  5  -  feet.  In  all  cases  parapet  fire  walls  should  be 
corbeled  out  at  the  exterior  walls  so  as  to  cut  off  completely  the 
connection  of  cornice  or  gutter  between  the  sections. 

Wall  Columns.  —  The  protection  of  iron  or  steel  columns 
placed  wholly  or  partly  within  exterior  walls  is  neither  as  im- 
portant nor  as  difficult  as  is  the  case  with  isolated  or  free-standing 
columns,  —  first,  because  wall  columns  do  not  have  to  endure 
as  high  temperatures  as  those  columns  which  may  be  exposed 
to  flame  on  all  sides  at  one  and  the  same  time,  —  and,  second, 
because  a  solid  masonry  wall  serves  well  to  stiffen  and  brace  the 
balance  of  the  column  protection,  thus  insuring  that  stability 
of  position  which  is  so  desirable.  From  the  standpoint  of  corro- 
sion, however,  wall  columns  require  more  care  than  do  isolated 
columns. 

In  earlier  examples  of  fire-resisting  buildings,  a  column  was 
usually  placed  within  the  exterior  wall  to  within  4  inches  or 
8  inches  of  the  face  of  wall,  leaving  the  rest  of  the  shaft,  project- 
ing into  the  room  or  floor  space,  to  be  covered  by  hollow  tile  as 
in  the  case  of  isolated  columns. 

In  later  examples  hollow-tile  casings  have  been  carried  entirely 
around  the  columns,  so  that  the  masonry  wall  would  not  be 


WALL    CONSTRUCTION 


661 


relied  upon  as  the  only  external  protection.  Fig.  269  shows  the 
detail  used  in  protecting  the  wall  columns  in  the  Fisher  Building, 
Chicago,  in  which  case  steam  pipes  were  carried  up  in  corner 
recesses  in  the  hollow-tile  casings. 


FIG.  269.  — Wall  Column  Protection,  Fisher  Building,  Chicago. 

In  many  cases  wall  columns,  where  projecting  into  the  rooms, 
are  protected  simply  by  a  4-inch  brick  casing,  bonded  into  the 
masonry  wall.  Captain  Sewell  states  of  the  buildings  in  the 
San  Francisco  fire  that  "the  wall  columns  covered  with  4  inches 
of  brickwork  were,  except  in  one  building,  fairly  well  protected, 
so  far  as  I  was  able  to  determine." 

Also, 

The  4-inch  brick  protection  used  on  the  exterior  columns, 
and  also  on  some  interior  columns,  made  a  remarkably  good 
showing,  and  practically  without  exception  was  intact  and  as 
firm  as  before  the  fire.  This  coincides  with  the  experiences  in 
former  fires.* 

A  still  more  reliable  protection,  however,  is  shown  in  Fig.  270. 
The  entire  column  is  first  protected  by  concrete,  built  out  solidly 
to  a  rectangular  outline,  outside  of  which  the  terra-cotta  facing 
and  the  brick  pier  are  carried  as  shown. 

Not  less  than  8  inches  of  brickwork,  concrete,  or  well-filled 
terra-cotta  blocks  should  be  placed  between  steel  columns  and 
the  face  of  wall.  No  allowance  should  be  made  for  thin  slabs 
or  facings  of  stone.  In  setting  hollow  tile  around  exterior  col- 

*  National  Fire  Protection  Association  report  on  Baltimore  fire. 


662         FIRE   PREVENTION    AND    FIRE   PROTECTION 

umns,  all  of  the  points  noted  in  Chapter  XII  as  to  efficient 
methods  and  workmanship  should  be  followed,  exactly  as  for 
isolated  columns. 


FIG.    270.  —  Typical    Wall    Column,    Filene    Building,    Boston. 

As  a  protection  against  corrosion,  all  wall  columns  should 
preferably  be  coated  with  a  rich  cement  mortar  which  should 
cover  the  entire  metal  work,  without  cavities. 


CHAPTER  XXI. 
ROOFS,  SUSPENDED  CEILINGS,  FURRING. 

Importance  of  Roof  Construction.  —  Fire-resisting  roof 
construction  is  of  vital  importance  as  regards: 

(a)  The  spread  of  distant  fire,  as  in  a  conflagration. 

(b)  The  exclusion  of  nearby  exposure  fire. 

(c)  The  integrity  of  the  construction   against  falling  walls, 
3tc.,  and 

(d)  The  confining  of  internal  fire. 

The  requirement  for  excluding  fire  of  very  moderate  severity, 
whether  from  nearby  exposure  or  from  a  distant  source,  is  usually 
ulfilled  by  providing  a  fire-resisting  roof  covering  which  will 
act  as  efficient  protection  against  heat,  sparks  or  embers.  With- 
n  all  city  limits,  at  least,  this  requirement  should  be  obligatory 
'or  all  classes  of  buildings.  This  would  mean  the  prohibition 
of  shingle  roofs,  which,  in  the  Paterson  conflagration,  were  set 
on  fire  in  numerous  places  distant  nearly  half  a  mile  from  the 
main  source  of  fire.  The  Chelsea  conflagration  resulted  in 
similar  experiences. 

To  resist  more  severe  exposure,  the  roof  covering  must  be 
reinforced  by  a  fire-resisting  roof  structure,  and  where  the 
walls  of  adjacent  buildings  extend  higher  than  the  roof  to  be 
constructed,  the  possibility  of  falling  walls  or  debris  and  the 
attendant  destruction  must  be  considered.  The  Baltimore  con- 
flagration showed  the  particular  necessity  of  making  the  roofs 
of  low  buildings  secure  against  the  exposure  attack  caused  by 
falling  walls  of  neighboring  higher  buildings.  It  was  thus  that 
fire  gained  entrance  into  several  of  the  lower  bank  buildings. 

To  confine  internal  fire  the  roof  must  act  as  a  perfect  barrier 
to  the  outburst  of  flame,  for  when  it  is  once  broken  through,  the 
intensity  of  the  fire  is  rapidly  increased  by  the  resulting  draught 
and  suction. 

In  buildings  as  ordinarily  constructed,  the  under  surface  of 
the  roof  will  receive  a  greater  concentration  of  heat  than  any 

663 


664 


FIRE    PREVENTION    AND    FIRE    PROTECTION 


other  surface  in  the  structure.  This  is  due  to  the  upward  rush 
of  flame  and  heated  air  by  means  of  vertical  courts  or  light  shafts 
or  stair-  and  elevator- wells. 

Classification  of  Roof  Structures  and  Coverings.* 


Type  of  Roof 

construc- 


1.   Fire-resisting 
tion : 


2.   Semi-fire-resisting : 
(Unprotected  metal  members.) 


Kind  of  Roof  Covering^ 

A.  Non-inflammable,  as  tile 

slate,  or  other  non-in- 
flammable slabs,  on 
any  mastic  or  plastic 
roofing  of  non-inflam- 
mable material. 

B.  Composition  (slag). 

C.  Prepared,  or  patent  roof- 

ings. 

D.  Non-inflammable  (as  A) . 

E.  Copper  on  metal. 

F.  Composition  on  non-in- 

flammable backing. 

G.  Flat  tile  on  metal. 

H.    Corrugated-iron  on 

metal. 

I.   Tin  on  wood  backing. 
J.   Composition     on     wood 

backing. 
Flat  tile  on  wood  back- 


K. 


ing. 


3.   Inflammable  Roof: 


L.  Flat  slate  on  wood  back- 
ing. 

M.  Corrugated-iron  on  wood 
backing. 

N.  Patent  or  prepared  roof- 
ings. 

O.   Wooden  roofings. 

P.    Tin  roofing. 

Q.    Composition. 

R.   Shingle  (flat)  tile. 

S.    Shingle  (flat)  slate. 

T.   Corrugated-iron. 

U.  Patent  or  prepared  roof- 
ings. 

V.    Wooden  roofings. 

The  letters  in  the  above  classification  of  roof  coverings  are 
for  reference  in  grouping  only,  and  do  not  necessarily  indicate 
preference  in  the  order  named. 

*  See  Report  of  Committee  on  Roofs  and  Roofings,  "  1908  Proceedings  o 
National  Fire  Protection  Association." 

t  For  a  classification  of  roof  coverings  according  to  test  specifications,  i 
page  680. 


ROOFS,  SUSPENDED    CEILINGS,  FURRING  665 

Fire-resisting  Roof  Structures  should  invariably  be  pro- 
vided for  buildings  intended  to  be  fire-resisting  in  the  least 
degree.  The  disastrous  results  from  using  combustible  or  unpro- 
tected steel  roof  structures  in  otherwise  fire-resisting  buildings 
have  been  pointed  out  in  Chapter  VI. 

Buildings  of  steel-frame  or  reinforced-concrete  construction 
are  usually  provided  with  fire-resisting  roofs.  In  such  buildings 
the  roof  framing  and  the  roof  arches  are  made  lighter  than  the 
framing  and  arches  for  the  floors,  as  most  building  laws  prescribe 
live  loads  to  cover  snow  and  wind,  etc.,  which  are  less  than  the 
live  loads  required  for  floor  systems.  The  dead  load  is  also  less, 
in  that  the  partition  loads  are  omitted. 

These  reductions  in  loading  make  it  possible  to  employ  terra- 
cotta or  hollow  tile  in  the  form  of  flat  arches  of  shallower  depth 
than  is  ordinarily  employed  in  floor  construction,  or  light  seg- 
mental  arches,  with  or  without  raised  skewbacks.  If  a  still 
lighter  form  is  desirable,  roofing  tile  or  "book  tile"  may  be 
placed  on  tee-irons,  without  any  arches  between  the  beams  or 
girders,  provided  the  latter  are  protected  by  tile  or  concrete. 

In  concrete  construction,  the  same  general  details  are  used 
for  roofs  as  for  floors,  except  that  the  arch  or  slab  is  made  shal- 
lower and  lighter. 

For  ordinary  cases  of  roof  framing  the  roof  beams  are  sup- 
ported by  the  girders,  which  run  over  and  are  supported  by  the 
columns  of  the  top  story.  The  beams  and  girders  must  be  so 
arranged  as  to  give  a  sufficient  pitch  to  drain  the  water  to  the 
down  spouts,  as  most  conveniently  located,  unless  saddles  or 
water  sheds  are  to  be  graded  up  with  concrete  filling. 

Fire-resisting  roof  structures  may  be  subdivided  into  four 
general  types: 

1.  Flat  roof  and  ceiling  of  top  story  formed  by  the  same  con- 
struction. 

2.  Flat-roof  construction  with  suspended  ceiling  beneath. 

3.  Pitched  roofs. 

4.  Mansard  roofs. 

Flat  Roof  and  Ceiling  Combined.  —  This  type  of  roof  is  gen- 
erally limited  to  warehouses  or  manufacturing  buildings,  where 
a  level  ceiling  is  not  necessary  for  appearance.  Unless  the  roof 
beams  are  made  perfectly  level,  as  for  a  floor,  with  the  roof  pitch 
made  up  in  concrete  or  other  filling  over  the  arches,  the  result 
is  an  irregular  pitched  ceiling,  due  to  the  slope  of  the  roof  beams 


666 


FIRE   PREVENTION    AND   FIRE   PROTECTION 


for  draining  the  roof  surface.  This  is  not  objectionable  in  storage 
or  manufacturing  buildings,  and  this  form  is  generally  employed 
in  such  structures. 

Great  care  is  necessary  to  secure  the  thorough  fireproofing  of 
all  beams  and  girders,  and  the  recommendations  made  in  Chap- 


FIG.  271.  —  Concrete  Roof  Construction,  U.  S.  Public  Building,  San  Francisco. 

ters  XVII  and  XVIII  as  to  girder  protection  should  be  carefully 
followed. 

Roof  arches  may  be  made  of  hollow  tile,  —  flat,  segmental, 
or  of  long-span  or  combination  form,  —  all  as  per  types  pre- 
viously described  in  Chapter  XVII;  or  concrete  slab  construc- 
tion may  be  employed. 

Fig.  271  illustrates  the  concrete  and  expanded  metal  roof  used 


/Vitrified  Roofing  Tile 


FIG.  272.  —  Concrete  Roof  Construction,  U.  S.  Public  Building,  Los  Angeles. 

in  the  United  States  Public  Building  at  San  Francisco,  Cal. 
No.  18  gauge  expanded  metal  was  laid  over  the  roof  beams,  upon 
which  was  constructed  a  concrete  plate  3J  inches  thick  —  2J 
inches  above  the  expanded  metal,  and  1  inch  below  it.  The 
beams  were  protected  by  terra-cotta  shoe  blocks.  The  roof 
surface  was  made  of  five  layers  of  asphalt  roofing  felt  and  IJ-inch 
solid  flat  tile,  embedded  in  cement. 

Fig.  272  shows  the  deck-roof  construction  employed  in  the 
United  States  Court  House  and  Post  Office  Building  at  Los 


ROOFS,  SUSPENDED    CEILINGS,  FURRING  667 

Angeles,  Cal.  The  roof  slab  is  made  of  reinforced  stone  or 
gravel  concrete  varying  from  3  inches  to  7  inches  in  thickness, 
over  which  are  placed  five  layers  of  asphalt  felt,  laid  in  hot 
asphalt.  The  roof  covering  is  made  of  vitrified  roofing  tile 
6  by  9  by  |  inches,  bedded  and  jointed  in  approved  elastic  cement. 

Concrete  roofs  permit  the  radiation  of  heat  far  more  than 
mill-construction  or  hollow-tile  roofs.  A  method  used  to  remedy 
this  loss  of  heat  consists  of  applying  a  top  coat  of  cinder  concrete, 
made  of  1  part  cement  to  10  parts  cinders,  3  inches  to  6  inches 
thick.  This  is  applied  very  loosely  and  is  then  leveled  up  with 
a  float  coat.* 

Book-tile  Construction.  —  A  lighter  but  less  efficient  roof  and 
ceiling  construction  than  the  foregoing  is  made  by  placing  the 
beams  sufficiently  close  together  to  carry  3-inch  or  4-inch  tees, 
upon  which  are  laid  roofing-  or  "  book  "-tile.  Such  blocks  are 
commonly  12  inches  wide  by  18  to  24  inches  long,  by  3  inches  to 
4  inches  thick.  Rabbeted  ceiling  blocks  (see  later  paragraph 
" Roofing  and  Ceiling  Blocks")  are  also  sometimes  used,  either 
solid  or  hollow,  but  for  approximately  horizontal  load-bearing 
surfaces  the  rabbeted  blocks  are  considerably  weaker  than  the 
book-tile.  Either  style  is  stronger  when  made  hollow  than  when 
made  solid.  Porous  blocks  should  be  used  in  all  places  where 
the  attachments  of  flashings,  etc.,  are  required.  This  detail  is 
used  for  light  systems  of  roof  construction,  but  it  is  generally 
considered  more  expensive  than  ordinary  roof  arches,  especially 
for  large  areas.  The  weight  of  the  tee-irons  forms  a  large  item 
of  expense,  as  does  also  the  added  cost  of  protecting  the  sup- 
porting beams. 

As  against  external  fire,  a  tee-iron  and  book-tile  roof  will  give 
sufficient  protection,  but  it  will  not  offer  the  resistance  to  shock 
or  load  possessed  by  arch  construction.  This  is  important 
where  walls  or  portions  of  walls  of  adjacent  buildings  are  liable 
to  fall  upon  the  roof  surface  during  a  conflagration. 

Considering  internal  fire,  this  construction  usually  provides  no 
adequate  protection  for  the  under  sides  of  the  tees.  Where 
ordinary  book-tile  are  used,  the  tees  do  not  project  below  the 
bottom  surfaces  of  the  terra-cotta  blocks.  Where  rabbeted  tile 
are  employed,  the  plaster  coating  has  little  or  no  bond  to  the 
iron  surface,  and  the  protection  is  only  nominal.  This  difficulty 

*  Wm.  H.  Ham  in  "1911  Proceedings  National  Association  of  Cement 
Users,"  page  447.  • 


668         FIRE    PREVENTION    AND    FIRE    PROTECTION 

of  satisfactorily  fireproofing  the  tee-irons  renders  this  type  of 
roof  unsuitable  for  structures  intended  to  be  of  the  best  fire- 
resisting  construction,  unless  the  blocks  are  rabbeted  for  soffit 
tile,  as  shown  in  Fig.  278. 

Another  objection  lies  in  the  comparative  thinness,  as  this 
method  does  not  provide  a  good  insulation  against  changes  in 
temperature.  The  temperature  of  the  spaces  under  the  roof 
will  be  easily  affected  by  outside  changes,  and  condensation  will 
occur  under  even  slight  differences  in  temperature. 

Provision  for  Future  Stories.  —  In  cases  where  provision  must 
be  made  for  future  stories  to  be  added,  the  roof  of  the  top  story 
may  be  constructed  like  a  typical  floor,  above  which  may  be 
placed  tee-irons  and  book-tile,  pitched  for  watershed. 

Flat  Roofs  with  Suspended  Ceilings.  —  Where  appearances 
must  be  considered,  as  in  mercantile  or  office  buildings,  hotels, 


FIG.  273.  —  Roof  with  Suspended  Ceiling,  U.  S.  Appraisers'  Warehouse,  N.  Y. 

etc.,  a  level  ceiling  must  be  provided  under  the  sloping  roof 
surface.  This  is  generally  accomplished  by  suspending,  a  light 
ceiling  construction  from  the  roof  beams. 

This  does  not  change  the  roof  construction  itself  in  any  way 
from  the  preceding  form.  The  same  general  details  are  used, 
with  the  addition  of  the  suspended  ceiling  for  the  sake  of  appear- 
ance. Fig.  273  shows  the  roof  and  ceiling  construction  employed 
in  the  United  States  Appraisers'  warehouse,  New  York  City,  in 
which  the  roof  consists  of  a  3-inch  plate  of  concrete,  with  ex- 
panded metal  embedded  therein,  over  which  are  laid  two  layers 
of  asphalt,  \  inch  thick  each,  for  the  finished  roof  surface.  The 
suspended  ceiling  is  made  of  2-inch  by  2-inch  tees,  suspended 
under  alternate  beams,  upon  which  rest  l|-inch  by  IJ-inch  tees, 
spaced  16  inches  centers,  to  receive  the  expanded  metal  lath  and 
plaster. 

Other  forms  of  suspended  ceilings  are  described  in  a  later 
paragraph. 


ROOFS,  SUSPENDED    CEILINGS,  FURRING  669 

Roof  Spaces.  —  Where  a  suspended  ceiling  is  used,  all  spaces  . 
between  the  ceiling  and  the  roof  should  be  made  inaccessible 
and  no  pipes  or  other  mechanical  features  should  be  located  in 
such  voids.  This  is  to  make  sure  that  no, one  may  have  cause 
to  visit  these  places  and  leave  the  means  of  communication  open. 
All  stair- wells,  skylights  or  light-courts  which  may  extend  up 
through  the  ceiling  to  the  roof  level  should  be  thoroughly  ceiled 
up  between  the  ceiling  and  the  roof  by  means  of  fire-resisting 
partitions.  These  should  extend  entirely  around  the  openings. 

Protection  of  Roof  Framing.  —  In  using  suspended  ceilings 
under  roofs  or  elsewhere,  the  thorough  fireproofing  of  the  steel 
members  over  the  ceiling  should  never  be  omitted,  however  thor- 
ough the  ceiling  construction  may  be  made.  In  this  respect 
the  roof  shown  in  Fig.  273  is  open  to  severe  criticism.  It  is  not 
safe  to  assume  that  any  ordinary  form  of  suspended  ceiling  will 
successfully  resist  a  long-continued  or  very  severe  fire.  Metal 
lath  and  plaster  or  thin  terra-cotta  ceiling  blocks  supported  on 
light  tee-irons  have  been  repeatedly  demonstrated  insufficient 
for  resisting  severe  conditions.  It  should  also  be  remembered, 
as  previously  pointed  out,  that  the  roof,  or  the  ceiling  of  the  top 
story,  will  receive  the  severest  test  by  heat  of  any  ceiling  or 
floor  in  the  building,  provided  any  stair-,  elevator-  or  light-shafts 
exist  by  which  the  fire  may  travel  upward.  Under  these  con- 
ditions, the  ceiling  must  be  considered  as  just  so  much  added 
protection  for  the  roof,  and  not  as  a  substitute  for  adequate 
fireproofing  of  the  roof  itself. 

Pitched  Roofs  are  sometimes  employed  in  thoroughly  fire- 
resisting  buildings,  but  oftener  in  buildings  like  factories,  etc., 
which  are  either  of  mill  or  partly  fire-resisting  construction.  In 
either  case  the  pitched  roof  is  usually  made  necessary  by  the 
employment  of  roof  trusses. 

Protection  of  Roof  Trusses.  —  Fire-resisting  buildings  in  which 
pitched  roofs  are  sometimes  used  include  armories,  churches, 
and  other  buildings  of  a  public  nature,  in  which  large  areas  are 
required  to  be  covered  by  roof  trusses  without  the  aid  of  interior 
columns.  The  trusses  usually  support  the  rafters,  which,  in 
turn,  carry  the  purlins,  placed  close  enough  together  to  receive 
the  roof  covering. 

The  attention  bestowed  upon  the  fireproofing  of  such  truss 
members  should  be  in  direct  proportion  to  the  importance  of 
the  service  rendered.  This  means  that  the  roof  trusses  them- 


670          FIRE   PREVENTION   AND   FIRE   PROTECTION 

selves  should  receive  the  greatest  consideration,  next  to  which 
come  the  rafters  and  then  the  purlins ;  for  if  the  trusses  fail,  the 
entire  structure,  or  roof  portion  at  least,  will  suffer  almost  com- 
plete destruction.  A  case  in  point  was  the  collapse  of  the  roof 
trusses  in  the  Cincinnati  Chamber  of  Commerce,  as  described 
on  page  204. 

Few  definite  rules  can  be  laid  down  for  the  successful  fire- 
proofing  of  truss  members.  The  details  finally  adopted  will 
depend  largely  upon  the  specific  considerations  to  be  met  and 
the  ingenuity  with  which  the  difficulties  may  be  overcome. 
In  general,  it  may  be  said  that  all  truss  members  and  rafters 
should  be  surrounded  by  complete  envelopes  of  terra-cotta  or 
concrete,  either  of  which  should  be  securely  held  in  position  by 
mechanical  means. 

Terra-cotta  coverings  should  be  applied  in  the  same  manner 
as  described  for  beam-  and  girder-protections  in  Chapter  XVII. 
When  the  best  possible  terra-cotta  envelope  has  been  secured, 
all  members  should  then  be  well  wired,  or  preferably  wrapped 
with  wire  or  metal  lath,  to  which  a  thick  coat  of  mortar  should 
be  applied.  For  this  purpose,  no  better  mortar  or  plaster  can  be 
used  than  "fire  mortar"  which  consists  of  a  fire  clay,  without 
lime  or  cement.  This  may  be  spread  on  to  a  thickness  of  f  inch, 
and  allowed  to  dry  in  place.  Fig.  274  indicates  methods  which 
may  be  employed. 

If  concrete  is  used  as  the  protective  envelope,  the  various 
members  should  be  well  wrapped  with  wires  or  netting,  after1 
which  the  concrete  may  be  poured  into  the  surrounding  forms 
so  as  to  give  not  less  than  1J  inches  of  concrete  beyond  the 
boldest  perimeter.  The  difficulty  of  placing  forms  makes  this 
character  of  concrete  work  very  expensive. 

Roof  Surfaces.  —  For  the  roof  surface,  details  similar  to  those 
described  for  flat  roofs  may  be  employed,  with  either  tile  arches 
or  concrete  slabs  sprung  from  rafter  to  rafter,  or  book-  or  roofing- 
tile  laid  between  the  purlins. 

Where  terra-cotta  arches  are  sprung  from  rafter  to  rafter  or 
from  purlin  to  purlin,  segmental  forms  are  preferable,  provided 
sufficient  depth  to  reinforce  the  haunches  with  concrete  filling 
can  be  obtained. 

Pitched  concrete  roofs  can  be  successfully  constructed,  and 
if  the  rafters  are  placed  8  feet  centers  or  less,  no  purlins  are  neces- 
sary to  receive  the  construction.  Three-inch  reinforced  slabs 


ROOFS,  SUSPENDED    CEILINGS,  FURRING 


671 


have  been  successfully  used  up  to  spans  of  6  feet  or  7  feet,  and* 
in  some  cases  even  8  feet.  The  concrete  is  deposited  upon 
wooden  centerings,  as  in  floor  construction,  and  the  upper  side 
is  smoothed  off  during  the  setting,  and  then  is  floated  smooth 
and  straight  to  receive  the  roof  covering.  Uncovered  concrete 


FIG.  274.  —  Fireproofing  of  Steel  Roof  Trusses. 

should  not  be  used  for  roof  surfaces  as  the  heat  of  the  sun  will 
soon  cause  cracks. 

Slate  or  tile  may  be  nailed  directly  to  cinder  concrete,  with- 
out the  use  of  wooden  nailing  strips.  Such  concrete  holds  the 
nails  nearly  as  well  as  does  wood.  For  roofs  where  a  nailing 
surface  is  required,  the  cinders  used  should  be  screened  through 
a  1-inch  mesh. 

For  concrete  roofs,  the  rafters  and  purlins  may  be  protected 
by  surrounding  them  with  concrete  at  the  same  time  that  the 
roof  slabs  are  formed. 


672 


FIRE    PREVENTION    AND    FIRE    PROTECTION 


Book-  or  roofing-tile  may  be  used  for  the  roof  surface  as  shown 
in  Fig.  274.  These  are  made  in  lengths  up  to  24  inches  (see 
page  678),  but  too  much  confidence  should  not  be  placed  in  the 
strength  when  made  in  such  long  lengths.  To  guard  against 
the  possibility  of  failure  by  the  breaking  of  long  blocks,  especially 
in  armory  roofs,  etc.,  where  vibration  is  liable  to  occur,  the  best 
work  requires  the  whole  under  surface  of  the  roof  to  be  covered 
with  a  coarse  wire  netting  of  2-inch  mesh.  This,  when  plastered, 
gives  a  finished  ceiling. 

For  use  between  purlins,  rabbeted  blocks  with  soffit  tile  are  much 
to  be  preferred  to  book-tile,  as  explained  in  a  later  paragraph. 

Where  nailing  surfaces  are  required,  as  for  slates,  the  book-  or 
roofing-tile  should  be  of  full  porous  material  with  thick  shells. 

Mansard  Roofs.  — -  Inclined  members  for  mansard  roofs  may 
be  the  only  supports  for  the  roof  surface,  in  which  case  they  are 


FIG.  275.  —  Mansard  Roof  Construction,  U.  S.  Public  Building,  Los  Angeles. 


ROOFS,  SUSPENDED    CEILINGS,  FURRING 


673 


usually  made  of  4-,  5-  or  6-inch  rafters,  with  roofing-tile,  parti- 
tion blocks,  or  even  terra-cotta  or  concrete  arches  between;  or 
the  inclined  members  may  support  purlins,  as  in  pitched  roofs. 
The  same  general  details  of  construction,  are  employed  as  for 
pitched  roofs,  but  as  the  principal  members  of  the  mansard 
usually  help  to  support  the  horizontal  roof  above,  the  covering 
or  fireproofing  of  the  supporting  rafters  should  be  considered  as 
important  as  that  of  the  trusses  or  columns. 

The  general  construction  of  the  mansard  roof  of  the  United 
States  Court  House  and  Post  Office  Building  at  Los  Angeles,  Cal., 
is  shown  in  Fig.  275.  A  horizontal  section  between  the  main 
mansard  rafters  is  shown  in  Fig.  276.  The  tile  arches  have  one 


\         \ 


SECTION  A  A 


Hpok^flattenedto  ^  th.  by 
M'Wide,  ab't  3"lg. 

FIG.  276.  —  Arches  between  Mansard  Rafters,  U.  S.  Public  Building, 
Los  Angeles. 

f-inch  tie-rod  to  each  arch.  Over  the  arches  are  placed  4-inch 
by  4-inch  beveled  nailing  strips,  each  secured  to  the  tile  by 
means  of  4  one-quarter-inch  hook  bolts,  placed  in  joints  of  arch 
as  shown.  Nailing  strips  are  coated  with  hot  asphalt,  and  be- 
tween them  the  tile  arches  are  finished  outside  with  a  1-inch  coat 
of  1  :  3  mortar.  The  roof  covering  is  14-ounce  hot-rolled  copper, 
secured  to'nailing  strips  by  cleats. 

Semi-flre-resisting  Roof  Structures.  —  In  the  classification 
of  roofs  previously  given,  those  of  semi-fire-resisting  qualities  would 
include  constructions  wherein  incombustible  but  unprotected  roof 
structures  are  covered  by  roof  coverings  possessing  more  or  less 
fire-resistance.  Such  constructions,  while  able  to  resist  the  spread 
of  distant  fire,  and  even  moderate  nearby  exposure  fire,  are  prac- 
tically worthless  for  resisting  interior  fire  of  any  severity,  unless 
the  building  is  well  sprinkled,  and  even  then  the  result  would  be 
problematical  in  a  fire  attaining  any  great  headway. 


674          FIRE    PREVENTION    AND    FIRE    PROTECTION 

Unprotected  Steel-roof  Structures.  —  It  is  a  well-recognized  fact 
that  unprotected  steel-roof  structures,  whether  flat  or  trussed, 
are  even  worse  than  useless  as  far  as  fire-resistance  is  concerned, 
on  account  of  their  liability  to  "wilt"  or  collapse,  thus  com- 
pletely wrecking  the  building  and  adding  greatly  to  the  fire 
damage,  besides  endangering  the  firemen.  Numerous  mill  and 
factory  fires  have  shown  such  results  in  trussed  roofs,  while  the 
Home  Store  Building  and  the  Roosevelt  Building,  described  in 
Chapter  VI,  were  typical  of  other  unprotected  flat  roofs  which 
have  been  quickly  and  completely  destroyed  by  fire.  Another 
example  was  the  burning  of  the  large  machine  shop  of  the  Brown 
Hoisting  Machinery  Company,  Cleveland,  Ohio,  wherein  a  good 
fire  department  and  ample  hose  streams  failed  to  save  the  build- 
ing, although  it  contained  little  combustible  structural  material 
save  floors,  windows  and  roof.  The  patenting  of  "  Ferroinclave  " 
by  this  firm  (see  pages  269  and  796)  was  a  direct  outcome  of 
that  fire  in  an  attempt  to  secure  a  fire-resisting  roofing  material 
which  should  prevent  similar  experiences. 

As  far  as  both  the  integrity  of  the  structure  and  the  safety  of 
firemen  are  concerned,  properly  constructed  wood  trusses,  as 
used  in  mill  buildings,  are  preferable  to  unprotected  steel  trusses. 

Examples  of  unprotected  steel  trusses  for  factories,  machine 
shops,  etc.,  are  given  in  Chapter  IV;  while  roof  coverings  of 
satisfactory  fire-resisting  qualities,  particularly  suited  to  such 
constructions,  are  described  on  page  684,  etc.  (see  also,  paragraph 
"Roofs,"  Chapter  XXV,  page  795). 

Fire  Curtains.  —  In  machine  shops,  mills,  etc.,  where  very 
long  undivided  areas  are  spanned  by  roof  trusses,  —  whether 
protected  or  unprotected,  —  the  use  of  fire  curtains  is  advisable. 
They  should  be  placed  at  intervals  —  generally  between  each 
division  of  the  sprinkler  equipment.  This  will  permit  the 
sprinkler  heads  on  each  side  of  such  curtains  to  be  fed  by  inde- 
pendent risers,  and  in  the  event  of  fire  the  curtains  will  also 
confine  the  heat  to  a  limited  area,  thus  opening  a  limited  number 
of  sprinkler  heads,  and  thereby  preventing  the  overtaxing  of  the 
water  supply,  and  at  the  same  time  lessening  the  water  damage. 

If  the  building  is  not  equipped  with  sprinklers,  fire  curtains 
at  intervals  will  help  stay  the  spread  of  fire  under  the  roof  sur- 
face, thereby  rendering  the  chance  of  control  more  likely. 

A  fire  curtain  is  made  by  covering  the  entire  area  of  a  roof 
truss  with  a  solid  fire-resisting  construction  which  should  fit 


ROOFS,  SUSPENDED   CEILINGS,  FURRING  675 

tightly  at  the  roof,  so  that  neither  fire  nor  heat  may  pass  through 
or  over  it.  It  may  be  constructed  of  metal  lath  with  cement 
plaster,  or  of  galvanized  corrugated-iron,  and  is  best  fastened 
directly  to  the  sides  of  the  truss  and  to  an  angle-iron  secured  to 
the  under  side  of  the  roof  surface. 

Attic  Spaces.  —  An  attic  or  storage  place  is  frequently  pro- 
vided between  the  ceiling  of  the  top  story  and  the  roof.  In 
this  case  the  attic  floor  acts  as  a  ceiling  and  as  a  floor  at  the  same 
time,  but  the  construction  is  generally  made  lighter  than  for 
regular  floors,  due  to  the  reduced  loads  which  it  is  intended  to 
carry.  The  clear  attic  space  varies  according  to  circumstances, 
but  it  is  frequently  made  3  feet  to  4  feet  high  at  the  lowest  por- 
tions, running  up  to  even  6  feet  or  7  feet  at  the  highest  points, 
due  to  the  roof  pitch. 

In  some  instances  the  roof  has  been  supported  from  the  attic 
floor  by  means  of  struts,  in  which  case  the  attic  floor  receives 
the  roof  loads,  as  well  as  its  own  loads. 

For  a  fire-resisting  building,  or  indeed  for  any  class  of  struc- 
ture, attic  spaces  should  be  studiously  avoided  where  possible. 
Such  unfrequented  spaces  are  very  liable  to  be  stored  with 
rubbish  or  light  materials,  which  are  extremely  combustible; 
and  if  fires  are  once  started  in  these  areas,  they  are  most  inacces- 
sible, and  are  likely  to  be  little  noticed  until  of  considerable 
magnitude. 

If  an  attic  space  is  considered  indispensable,  all  steelwork 
therein  should  be  adequately  protected.  Numerous  fires,  in- 
cluding Baltimore,  have  demonstrated  the  folly  of  neglecting 
this  requisite. 

Roof  Houses,  etc.  —  In  cases  where  stair  wells  or  elevator 
shafts  are  not  surrounded  by  brick  walls,  or  where  masonry  walls 
are  used  but  are  not  carried  up  through  the  roof,  pent  or  roof 
houses  are  constructed  of  steel  framework  and  terra-cotta  blocks, 
or  of  concrete.  Either  flat  or  double-pitched  roofs  are  used 
thereover,  with  or  without  skylights,  as  may  be  required. 

The  steel  framework  is  usually  made  of  vertical  3-inch  tee- 
irons,  spaced  about  18  inches  centers,  with  angles  at  the  corners 
and  at  door  or  window  openings.  A  horizontal  frame  or  plate 
made  of  angles  or  channels  surrounds  the  top,  and  provides,  a 
seat  for  the  skylights  or  roof  tees  or  beams. 

In  pent  houses  surrounding  elevator  shafts,  where  the  sheave 
beams  are  connected  to  the  pent-house  frame,  thus  causing  con- 


676         FIRE    PREVENTION    AND    FIRE    PROTECTION  _. 

stant  vibration,  the  flanges  of  the  tee  uprights  should  be  placed 
on  the  inside.  The  blocks  are  then  placed  from  the  outside,  and 
if  they  become  loose  from  vibration,  the  tees  will  prevent  their 
falling  inward,  while  the  outside  covering  of  tin  or  copper  will 
keep  the  tile  hugged  in  place. 

The  same  construction  is  often  employed  for  "  sky  light  curbs," 
where  skylights  are  placed  several  feet  above  the  roof  level  as 
described  under  following  paragraph  "  Skylights." 

All  doors  and  windows  in  roof  houses  of  fire-resisting  buildings 
should  be  " standard,"  as  described  in  Chapter  XIV. 

Scuttles.  — 

Construction.  —  (a)  If  on  buildings  of  fireproof  construc- 
tion to  be  of  (1)  No.  12  gauge  sheet  iron  or  steel,  reenforced  by 
2-by  2-by  J-inch  angle  iron,  or  (2)  double-battened  wood,  stand- 
ard tin-clad  on  all  sides,  edges  and  in  all  angles,  and  be  provided 
with  proper  chafing  plates  where  fitting  over  combing. 

(b)  If  on  buildings  of  slow-burning  construction  to  be  as 
noted  under  (a),  this  section,  or  of  double-battened  wood,  tin- 
clad  on  the  outside,  the  tinning  to  return  over  the  lower  edges. 

(c)  On  other  buildings,  if  not  in  accordance  with  the  fore- 
going, to  be  thoroughly  tin-clad  on  the  outside,  the  tinning  to 
return  over  the  lower  edges. 

Fastening.  —  All  scuttles  are  to  be  fastened  by  means  of 
strong  steel  or  wrought-iron,  galvanized  hinges,  bolted  to  scuttle 
and  combing  or  roof. 

Stops.  —  All  scuttles  to  be  provided  with  suitable  stops, 
consisting  preferably  of  a  strong  chain,  bolted  to  scuttle  and 
combing,  allowing  the  scuttle  to  open  slightly  beyond  a  vertical 
position. 

Ladders.  —  Permanent  ladders  should  be  provided,  giving 
access  to  scuttles.* 

Skylights.  —  Construction. 
Glass. 

(a)  For  all  skylights,  plane  or  inclined  not  over  45  degrees, 
to  be  either  of  standard  wired  glass  not  less  than  ^-inch-thick  or 
i-inch-thick  glass  protected  with  approved  wire  screens.     Panes  to 
be  not  over  18  or  20  inches  wide,  and  not  to  exceed  720  square 
inches  in  area. 

(b)  For  vertical  skylights  or  sash,  or  such  as  are  inclined 
at  an  angle  of  over  45  degrees,  may  be  wired  glass  as  noted  under 
(a)  J-inch-thick  glass  without  screens,  or  glass  not  less  than 
i  inch  thick,  provided  the  sash  or  skylights  are  protected  by 
suitable  screens. 

(c)  For  vertical  skylights  or  sash,  or  such   as  are  inclined 
at  an  angle  of  over  45  degrees,  when  exposed  in  such  a  manner 

*  From  "  Rules  and  Requirements  of  the  National  Board  of  Fire  Under- 
writers" covering  "Skylights,"  etc. 


ROOFS,  SUSPENDED   CEILINGS,  FURRING  677 

that  the  wall  openings  in  buildings  would  require  standard  fire 
shutters  or  standard  wired  glass  (or  doors)  against  such  exposures, 
standard  wired  glass  only  must  be  used. 

(d)  For  skylights  over  fireproof  stair,  elevator,  dumbwaiter, 
air  or  similar  shafts,  not  over  |-inch  glass,  either  on  top  or  at 
sides  of  cupola  skylight,  if  surmounted  by  that  type,  protected 
by  suitable  screens. 

(e)  For  skylights  over  stage  sections  of  theaters  not  over 
J-inch  glass,  protected  by  suitable  screens. 

NOTE.  Substitutes  for  glass  such  as  wire  cloth  with  a  coating  of  translucent 
combustible  substance  or  similar  materials  are  not  approved. 

Sash. 

(a)  Materials.  —  Sash  to  be  constructed  entirely  of  metal, 
either  galvanized-iron,  wrought-iron  or  angle-iron. 

(b)  Construction.  —  To  be    constructed    with    interlocking 
seams  or  rivets  in  accordance  with  the  rules  and  requirements  of 
the  National  Board  of  Fire  Underwriters  for  wired  glass  windows. 

(c)  Glazing.  —  Glass  to  be  secured  to  the  sash  by  means 
of  metal  strips  held  in  position  by  bolts  or  screws  in  such  a  man- 
ner as  to  form  joints  sufficiently  elastic  to  allow  for  proper  expan- 
sion and  contraction,  and  to  be  weatherproof. 

Frames. 

Frames  for  low,  flat  or  small  cupola  skylights  to  be  entirely 
of  galvanized-iron  secured  to  angle-irons,  all  properly  riveted 
together  and  securely  fastened  to  roof.  All  joints  to  be  tight 
and  weatherproof. 

Curbs  for  Skylights. 

(a)  If  on  buildings  of  fireproof   construction,  to    be    con- 
structed of  approved  fireproof  materials  reenforced  with  angle- 
iron  properly  protected  by  approved  fireproof  material. 

(b)  If  on  buildings  of  slow-burning   construction,  may  be 
either  (1)  of  not  less  than  4-  by  4-inch  framework,  filled  in  with 
brick,  terra-cotta,  cement  or  other  approved  fireproof  materials, 
tin-clad  on  the  outside;  (2)  double  boarded,  tongued  and  grooved 
boards  at  right  angles  to  each  other,  tin-clad  on  the  outside;   (3) 
of  not  less  than  2 f -inch  tongued  and  grooved  or  splined  plank, 
tin-clad  on  the  outside. 

(c)  On  all  other  buildings,  if  not  in  accordance  with  the 
foregoing,  to  be  thoroughly  tin-clad  on  the  outside. 

(d)  Curbs    must    be   securely    fastened   to   framework   of 
roof,  and  when  on  roofs  of  joisted  construction  must  be  supported 
on  doubled  joists.* 

Roofing  and  Ceiling  Blocks.  —  Hollow-tile  blocks  used  for 
roofing  and  ceiling  purposes  are  made  in  three  distinct  patterns, 
viz.,  " book-tile,"  which  have  either  tongue  and  groove  edges 
or  curved  edges,  thus  resembling  the  shape  of  a  book,  —  roofing 

*  For  further  Rules  and  Requirements  covering  Monitor,  Saw-tooth  and 
Theater  Skylights,  etc.,  see  regulations  covering  "Skylights,"  National  Board 
of  Fire  Underwriters. 


678 


FIRE    PREVENTION    AND    FIRE    PROTECTION 


blocks,  or  plain  rectangular  tile  similar  to  thin  partition  blocks,  — 
and  rabbeted  blocks,  usually  called  ceiling  blocks.  These  three 
types  are  shown  in  Fig.  277,  A,  B  and  C  respectively. 

Book-tile  and  roofing  blocks  are  made  of  porous  or  semi-porous 
material,  in  the  following  standard  sizes  and  weights: 

3  X  12  X  18  inches  —  20  pounds  per  square  foot. 
3  X  12  X  20  inches  —  20  pounds  per  square  foot. 

3  X  12  X  24  inches  —  20  pounds  per  square  foot. 

4  X  12  X  24  inches  —  22  pounds  per  square  foot. 

If  the  roof  is  approximately  flat,  and  covered  with  felt  or  com- 
position roofing  or  with  concrete,  3-inch  or  4-inch  blocks  accord- 


FIG.  277.  —  Roofing  and  Ceiling  Blocks. 

ing  to  the  weight  and  span  are  commonly  used.  Three-inch 
blocks  are  generally  sufficient.  If  the  roof  has  a  considerable 
slope,  as  in  mansards,  or  if  roofing  tile  of  slate  or  other  material 
are  to  be  attached,  the  blocks  should  be  3-inch  full  porous,  with 
exterior  shells  not  less  than  1J  inches  thick. 

If  saddles  are  necessary  to  care  for  drainage,  they  may  be 
made  by  concrete  filling,  but  for  most  roof  coverings  the  top 
surface  of  book-  or  roofing-tile  construction  will  be  found  smooth 
enough  without  top  concreting  or  cementing,  provided  all  top 
joints  are  well  pointed  and  provided  uneven  surfaces  are  finished 
flush  with  well-troweled  cement  mortar. 

The  supporting  tees  should  be  spaced  one  inch  wider  than  the 
length  of  the  blocks.  Thus  for  the  usual  24-inch  block,  the  tees 
should  be  placed  25  inches  centers. 


ROOFS,  SUSPENDED    CEILINGS,  FURRING  679 

If  the  construction  is  as  shown  in  Fig.  277,  A  or  B,  no  protec- 
tion is  afforded  the  soffits  of  the  tees,  as  even  a  very  thick  coat 
of  plaster  on  the  under  side  of  the  book  tile  will  not  give  more 
than  a  skim  coat  under  the  tees.  If  made  as  per  Fig.  277,  C, 
the  plastering  will  cover  the  tee  soffits,  but,  having  no  bond,  it 
is  of  little  value.  For  such  cases,  especially  if  the  tee  flanges 
are  wide,  they  may  be  wrapped  with  wire  lath  before  the  blocks 
are  set.  This  will  form  a  key  for  the  plastering,  but  even  this 
detail  is  not  efficient  for  conditions  of  any  severity.  To  really 
protect  the  tees,  4-inch  rabbeted  blocks  should  be  used,  as  shown 
in  Fig.  278.  Such  blocks  are  made  to  drop  one  inch  below  the 


_ 
t 

FIG.  278.  —  Rabbetted  Roofing  Blocks. 

tee  flanges,  thus  allowing  the  use  of  shoe  tile  or  soffit  tile,  as  in 
arch  construction. 

Ceiling  blocks  are  made  of  all  grades  of  tile,  of  the  following 
standard  sizes  and  weights: 

2  X  12  X  16  inches] 

2  X  12  X  18  inchest  11  to  12  pounds  per  square  foot. 

2  X  12  X  20  inches' 

3  X  12  X  16  inchesl 


3  X  12  X  18  inches 
3  X  12  X  20  inches 


14  to  20  pounds  per  square  foot. 


3  X  12  X  24  inches 

4  X  12  X  24  inches,  porous,  18  pounds  per  square  foot. 

In  second-class  construction,  where  it  is  desirable  or  obligatory 
to  provide  a  more  or  less  fire-resisting  ceiling  over  boiler  rooms, 
bake  ovens,  or  drying  rooms,  etc.,  2-inch  ceiling  blocks  are  fre- 
quently used.  They  are  fastened  to  the  wood  joists  by  means 
of  wire  nails  or  screws  which  pass  through  metal  washers,  placed 
under  the  ceiling  blocks  and  lapping  the  joints. 

Gypsum  Roofing  Blocks  are  made  solid,  of  the  following  sizes: 

2  X  15  X  24  inches  —    9  pounds  per  square  foot. 

3  X  15  X  24  inches  —  13  pounds  per  square  foot. 


680         FIRE    PREVENTION   AND    FIRE   PROTECTION 

Roof  Coverings. —  Classification  and  Tests  of.  —  The  National 
Fire  Protection  Association's  "  Standard  for  Roof  Coverings  and 
Test  Specifications  for  their  Classification  " 

is  designed  to  afford  a  means  of  classifying  any  type  of  roof 
covering,  independently  of  the  roof  structure  upon  which  it  is 
applied,  by  the  establishment  of  six  general  groups  or  classes. 
These  classes  are  so  graded  that  the  roof  coverings  qualifying 
under  them  are  classified  in  accordance  with  the  amount  of  pro- 
tection afforded  the  roof  structure.  The  classes  are  established 
by  the  adoption  of  limiting  test  requirements  for  each  class.* 

This  classification,  which  is  subdivided  to  distinguish  between 
those  coverings  which  are  applicable  to  all  classes  of  roof  struc- 
tures and  those  which  are  limited  to  certain  inclinations  or  forms 
of  roof  structures,  may  be  briefly  summarized  as  follows: 

Class  A.  —  To  include  roof  coverings  which  afford  a  very 
high  degree  of  fire  protection  to  the  roof  structure;  which  are 
not  readily  flammable;  which  do  not  carry  or  communicate  fire; 
which  do  not  give  off  flammable  vapors  or  gases  in  large  volume 
when  exposed  to  high  temperatures;  which  possess  no  flying 
brand  hazard;  which  possess  considerable  blanketing  influence 
upon  fires  within  the  building;  and  which  are  durable  and  require 
repairs  or  renewals  only  at  very  infrequent  intervals.  .  .  . 

Class  B.  —  To  include  roof  coverings  which  afford  a  high 
degree  of  fire  protection  to  the  roof  structure;  which  are  not 
readily  flammable;  which  do  not  carry  or  communicate  fire; 
which  possess  little  or  no  flying  brand  hazard;  which  possess 
considerable  blanketing  influence  upon  fires  within  the  buildings; 
and  which  are  durable  and  do  not  require  frequent  repairs  or 
renewals.  .  .  . 

Class  C.  —  To  include  roof  coverings  which  afford  a  mod- 
erate degree  of  fire  protection  to  the  roof  structure;  which  are 
not  readily  flammable;  which  do  not  carry  or  communicate  fire; 
which  possess  little  or  no  flying  brand  hazard;  which  possess 
moderate  blanketing  influence  to  fires  within  the  building;  and 
which  are  durable,  but  which  require  renewals  at  fairly  infrequent 
intervals.  .  .  . 

Class  D.  —  To  include  roof  coverings  which  afford  a  slight 
degree  of  fire  protection  to  the  roof  structure;  which  are  not 
readily  flammable;  which  do  not  readily  carry  or  communicate 
fire;  which  possess  a  moderate  flying  brand  hazard;  which  pos- 
sess little  blanketing  influence  upon  fires  within  the  building,  and 
which  require  repairs  or  renewals  at  fairly  frequent  intervals.  .  .  . 

Class  E.  —  To  include  roof  coverings  which  afford  little  or 
no  fire  protection  to  the  roof  structure;  which  are  not  readily 
flammable;  which  do  not  readily  carry  or  communicate  fire; 
which  possess  a  moderate  flying  brand  hazard;  which  possess 

*  See  "1911  Proceedings  of  National  Fire  Protection  Association." 


ROOFS,  SUSPENDED    CEILINGS,  FURRING  681 

little  or  no  blanketing  influence  upon  fires  within  buildings;  and 
which  may  require  repairs  or  renewals  at  fairly  frequent  inter- 
vals. .  .  . 

Class  F.  —  To  include  roof  coverings  which  afford  little 
or  no  fire  protection  to  the  roof  structure;  which  are  readily 
flammable;  which  will  rapidly  carry  and  communicate  fire; 
which  possess  more  or  less  severe  flying  brand  hazard;  which 
possess  little  or  no  blanketing  influence  to  fires  within  the  build- 
ing; and  which  may  require  repairs  or  renewals  at  fairly  frequent 
intervals. 

The  Test  Specifications  require  that  roof  coverings,  before 
receiving  classification,  shall  be  subjected  to  tests  and  investiga- 
tions as  follows: 

1.  Flame  Exposure  Tests. 

2.  Burning  Brand  Tests. 

3.  "Radiation  Tests. 

4.  Investigation  to  determine  the  permanence  and  quality 
of  the  raw  materials  employed,  the  weathering  properties  and 
the  necessity  for  repairs  and  renewals  in  the  roof  covering  as 
applied  to  the  roof  structure. 

5.  Additional  tests  may  be  called  for  when,  in  the  judgment 
of  the  Underwriters'  Laboratories,  Incorporated,  they  are  deemed 
necessary. 

For  the  convenience  of  discussion,  roof  coverings  pertinent  to 
a  handbook  of  this  character  may  be  divided  into  two  general 
classes : 

1.  Those  suitable  for  use  on  fire-resisting  roof  structures,  (a) 
flat,  (b),  pitched. 

2.  Those  suitable  for  use  on  semi-fire-resisting  roof  structures 
usually  pitched. 

Wear  or  deterioration  wilt  often  seriously  impair  the  fire-pro- 
tection value  of  a  roof  covering,  so  that  the  weathering  and  wear- 
ing qualities  become  of  vital  concern,  not  only  as  regards  renewal 
and  satisfactory  service  under  ordinary  conditions,  but  as  affect- 
ing the  fire-resistance  as  well. 

Coverings  Suitable  for  Fire-resisting  Roof  Structures/— 

Flat  Roofs,  or  those  pitched  only  enough  to  drain  properly, 
may  be  covered  with  brick,  vitrified  roofing  tile,  slate  tile,  com- 
position or  slag,  or  incombustible  prepared  or  patent  roofings. 

Brick  Surfacings  are  thoroughly  fire-resisting  and  extremely 
durable,  and  should  easily  qualify  for  Class  A.  Only  their 
excessive  weight  has  prevented  a  more  extended  use,  but  if 
economy  need  not  be  especially  considered,  their  use  is  to  be 


682          FIRE    PREVENTION    AND    FIRE    PROTECTION 

highly  recommended  for  roof  decks  with  pitch  not  exceeding 
one  inch  per  foot.  The  cost  is  about  the  same  as  for  vitrified  tile. 

The  roof -structure  surface  should  first  be  coated  with  not  less 
than  140  pounds  (per  100  square  feet)  of  best  quality  hot  pitch 
cement  or  asphalt  cement.  The  bricks  are  then  laid  on  edge  in 
Portland  cement  mortar,  and  after  all  joints  are  well  set,  a  sur- 
face mopping  of  not  less  than  40  pounds  (per  100  square  feet) 
of  cement  is  applied.  This  mopping  may  be  omitted  where  the 
brick  are  set  in  mastic-tile  cement. 

Vitrified  Roofing  Tile  are  usually  one  inch  thick,  and  6  by  9, 
9  by  9,  or  9  by  12  inches  in  size.  They  weigh  about  9  pounds 
per  square  foot.  They  are  both  durable  and  fire-resisting,  and, 
when  laid  to  a  very  slight  pitch  —  preferably  not  over  one- 
fourth  inch  per  foot  —  would  be  included  in  Class  A.  For  a 
pitch  exceeding  one-fourth  inch  per  foot,  especially  under  the 
heat  of  a  fire  or  in  very  hot  weather,  the  tile  are  apt  to  slip, 
causing  a  buckling  up  at  joints. 

They  may  be  laid  flat,  exactly  the  same  as  previously  described 
for  brick,  except  that  they  should  be  bedded  in  a  one-inch  layer 
of  Portland  cement  mortar,  or  in  one-quarter  inch  or  more  of 
mastic-tile  cement.  Or,  after  making  the  roof  surface  perfectly 
smooth,  six  thicknesses  of  No.  1  wool  roofing  felt  —  weighing 
not  less  than  15  pounds  per  100  square  feet  —  may  be  laid, 
cemented  not  less  than  9  inches  between  each  layer  with  roofing 
cement.  The  tile  are  then  bedded  in  a  layer  of  actinolite  cement, 
the  joints  being  made  with  marmolite  cement. 

Slate  Tile  are  made  of  squares  of  black,  purple  or  green  slate, 
with  planed  under  surface,  and  planed  and  rubbed  top  surface  and 
edges.  They  are  usually  |  inch  or  1  inch  thick,  by  12  by  12  inches 
in  area.  Tile  12  inches  by  18  inches  are  sometimes  used  to  give 
fewer  joints.  They  make  a  most  excellent  roof  covering,  at  a  cost 
about  equal  to  vitrified  tile,  and  would  be  included  in  Class  A. 

The  usual  method  of  laying  consists- of  an  under  waterproofing, 
made  of  five  thicknesses  of  either  tarred  felt  or  asphalt  felt 
mopped  between  each  layer  with  roofing-cement  asphalt.  The 
tile  are  then  bedded  and  jointed  in  refined  Trinidad  asphalt. 
Practical  roofers  advise  a  pitch  not  exceeding  J  to  J  inch  per 
foot,  on  account  of  possible  buckling,  as  explained  for  vitrified 
tile.  For  a  square,  or  100  square  feet,  the  weight  according  to 
the  above  specifications  would  be  75  pounds  for  felt,  150  pounds 
for  asphalt,  1300  pounds  for  slate,  or  15J  pounds  per  square  foot. 


ROOFS,  SUSPENDED    CEILINGS,  FURRING  683 

Composition  Gravel  or  Slag  Roofs  are  laid  on  a  concrete  sub- 
surface, either  concrete  roof  slabs,  or  concrete  surfacing  over 
hollow-tile  arches.  A  waterproofing  layer  of  five  thicknesses 
of  felt  is  then  applied,  exactly  the  same  as  for  slate  tile,  above 
described,  except  that  a  heavy  pouring  —  about  J  inch  —  of  hot 
asphalt  or  coal-tar  pitch,  with  gravel  or  finely  broken  slag  em- 
bedded therein,  is  substituted  for  the  tile. 

Not  less  than  200  pounds  of  pitch  or  asphalt  cement  per 
100  square  feet  of  completed  roof  to  be  used  on  inclines  less  than 
2  inches  to  the  foot,  nor  less  than  160  pounds  to  each  100  square 
feet  on  surfaces  exceeding  2  inches  to  the  foot.  Quantity  to  be 
varied,  according  to  roof  incline.* 

The  slag  or  gravel  to  be  of  such  a  grade  that  no  particles 
are  to  exceed  five-eighths  of  an  inch  or  be  less  than  one-fourth 
of  an  inch  in  size,  and  dry  and  free  from  all  dust  and  dirt. 

Not  less  than  300  pounds  of  slag  or  400  pounds  of  gravel 
to  be  used  per  100  square  feet. 

In  cold  weather  it  must  be  heated  immediately  before  using 
and  must  be  applied  perfectly  dry  and  while  cement  is  hot.* 

This  covering  would  probably  come  under  Class  B  when 
applied  either  to  fireproof  or  combustible  roof  decksj  and  where 
applied  at  inclines  not  exceeding  3  inches  to  the  foot. 

Note.  —  It  should  be  explained  that  the  specification  for 
this  particular  type  of  roof  covering  nominates  the  best  possible 
practice  in  the  construction  of  a  so-called  tar  and  gravel  roof. 
The  specifications*  for  the  felt  and  pitch  are  rigid,  and  call  for 
the  use  of  a  large  quantity  of  pitch  and  gravel.  Coverings  which 
depart  from  this  specification  by  reducing  the  quantity  of  gravel 
on  the  surface  and  the  quality  of  felt  and  pitch,  will  undoubtedly 
take  a  lower  classification.  In  fact,  many  of  these  coverings 
are  liable  to  aid  in  the  spread  of  fire  over  their  surfaces,  and  after 
being  subjected  to  the  weather  for  several  years  will  afford  but 
little  protection  to  the  roof  deck. 

The  limitation  relative  to  the  height  of  incline  is  considered 
to  be  the  maximum  allowable  height.  It  may  develop  from  the 
field  examination  that  it  will  be  necessary  to  decrease  this  limit. f 

Prepared  Roofing:  Asbestos  Felt.  —  There  are  a  number  of  pre- 
pared asbestos  roofings  and  also  so-called  built-up  asbestos  roof- 
ings which  are  sold  ready  to  lay,  for  either  combustible  or 
non-combustible  roof  structures.  A  specific  type  of  this  prepared 
roofing,  made  up  of  plies  of  asbestos  felt  paper  cemented  together 
with  an  asphaltic  cement,  "will  fall  in  Class  B  when  applied  to 
incombustible  roof  decks  and  possibly  in  Class  C  when  applied  to 
combustible  decks. "f 

*  Report  of  Committee  on  Roofs  and  Roofings,  "1908  Proceedings  of 
National  Fire  Protection  Association,"  page  139. 

t  "1911  Proceedings  of  National  Fire  Protection  Association,"  page  44. 


684 


FIRE    PREVENTION   AND    FIRE    PROTECTION 


Pitched  Roofs.  —  The  previously  described  roof  coverings  — 
except  prepared  roofings  of  asbestos  felt,  etc.,  which  are  consid- 
ered applicable  to  practically  any  incline  —  should  not  be  used  on 
roofs  having  any  considerable  pitch.  Where  the  previously  men- 
tioned inclines  are  exceeded,  coverings  may  be  as  follows: 

If  the  subsurface  is  of  stone  concrete,  prepared  roofings  may 
be  directly  applied,  or  copper  may  be  attached  to  nailing  strips 
as  shown  in  Figs.  275  and  276. 

If  cinder  concrete  is  used,  either  for  the  entire  roof  slabs  or 
as  a  filling  over  hollow-tile  arches,  or  if  full-porous  terra-cotta 
book-tile  are  used,  the  roof  covering  may  be  made  of  natural 
slate  shingles,  clay  tile,,  or  asbestos  roofing  shingles,  nailed  on. 
Vitrified  clay  tile  are  made  in  a  great  variety  of  forms,  flat, 
ribbed  and  corrugated;  but  those  of  some  interlocking  pattern 
are  best.  Clay  tile  will  resist  fire  better  than  natural  slate. 

Coverings  Suitable  for  Semi-fire-resisting  Roof  Struc- 
tures include  natural  slate,  interlocking  tile,  asbestos-corrugated 
sheathing,  asbestos-protected  metal,  and  "Ferroinclave."  As 
roof  structures  of  this  character  usually  consist  of  metal  roof 
trusses,  purlins  must  be  provided  at  sufficient  intervals  to  receive 
the  covering  contemplated. 

Slate  Shingles  should  not  be  used  for  slopes  less  than  40  de- 
grees. A  very  satisfactory  fastener*  for  attaching  the  slate  to 
the  T-iron  purlins,  as  used  on  many  United  States  Gov- 
ernment and  other  private 
buildings,  is  illustrated  in 
Fig.  279.  For  slates  24 
inches  long  as  generally 
used,  with  a  3-inch  lap  of 
top  slate  over  bottom  slate, 
the  purlins  should  be  spaced 
10J  inches  centers.  A  thick 
coating  of  plaster  is  usually 
applied  to  the  under  side  ol 
the  slating  and  around  the 
purlins,  to  prevent  the  pene 
tration  of  cold  and  draughts 
One-quarter  inch  thicl 

slates  —  which  should  be  a  minimum  thickness  —  laid  as  above 

will  weigh  10  pounds  per  square  foot  exclusive  of  purlins  or  plaster 

*  Patented  by  John  Farquhar's  Sons,  Boston,  Mass. 


FIG.  279.  —  Attachment  of  Slate  Shingles 
to  T-Iron  Purlins. 


ROOFS,  SUSPENDED    CEILINGS,  FURRING  685 

Roofing  Tile.  —  Those  of  interlocking  types  may  be  laid 
directly  on  steel  purlins  without  sheathing,  much  as  described 
above  for  slate  shingles.  They  are  usually  fastened  to  the 
angle  or  tee  purlins  by  means  of  copper  wires  which  are  run 
through  pierced  lugs  in  the  lower  ends  of  the  tile. 

Asbestos-corrugated  Sheathing  has  previously  been  described 
(see  Chapter  VII,  page  264). 

Asbestos-protected  Metal  has  also  been  described  in  Chapter  VII, 
page  268. 

u  Ferroinclave"  has  been  described  and  illustrated  in  Chapter 
VII  (see  page  269) .  When  used  as  a  roofing,  the  sheets  are  sup- 
ported by  purlins  made  of  any  suitable  steel  sections,  but  I's 
or  channels  are  preferable.  The  most  economical  spacing  for 
these  is  4  feet  10J  inches  centers,  the  same  as  for  siding.  Along 
the  tops  of  all  purlins  are  placed  f-inch  square  hardwood  strips, 
upon  which  the  ferroinclave  sheets  are  laid.  The  sheets  are 
then  attached  to  the  purlins  every  10  inches  by  means  of  clips, 
varying  in  shape  according  to  the  section  of  purlin  used.  Special 
cross  ties  or  steel  straps  are  clamped  across  the  side  laps  every 
two  feet. 

After  the  metal  sheets  are  all  in  place,  the  upper  surface  is 
plastered  with  a  mortar  made  of  one  part  Portland  cement  to 
from  two  to  two  and  one-half  parts  of  sand.  For  purlins  spaced 
4  feet  10J  inches,  this  coating  should  be  one-half  inch  thick 
above  the  tops  of  the  corrugations.  This  thickness  must  be 
increased  with  increased  spacing  of  purlins.  When  the  upper 
coating  has  thoroughly  set,  the  under  side  is  coated  with  the 
same  mixture  of  mortar  (with  the  addition  of  a  small  amount 
of  hair),  applied  f-inch  thick  below  the  corrugations.  It  should 
be  applied  in  three  coats,  each  succeeding  the  previous  one 
before  the  latter  is  set.  This  plastering  should  be  well  pushed 
in  between  the  tops  of  the  purlins  and  the  under  sides  of  the 
sheets,  as  it  is  for  this  reason  that  the  f-inch  square  wood  strips 
are  used. 

If  the  roof  is  of  slight  pitch,  a  covering  of  tarred  felt  and  slag 
or  gravel  should  be  applied.  If  the  incline  exceeds  3  inches  per 
foot,  some  prepared  roofing  is  advisable. 

The  weight  of  a  1  f-inch  roof,  exclusive  of  waterproof  covering, 
is  16  pounds  per  square  foot.  The  construction  described  is 
capable  of  carrying  an  ultimate  distributed  load  of  300  pounds 
per  square  foot,  after  ten  days. 


686          FIRE    PREVENTION   AND   FIRE   PROTECTION 

A  comparison  between  the  cost  of  "  f erroinclave  "  roofing  and 
tar  and  gravel  over  wood  sheathing  is  given  in  Chapter  XXV, 
page  796. 

Fire-resisting  Coverings  Suitable  for  Wooden  Roof 
StructureSs  and  to  be  recommended  as  substitutes  for  wood 
shingles,  include  natural  slate,  and  corrugated  or  interlocking 
clay  tile  as  previously  described,  —  except  that  they  may  be 
nailed  to  the  wood  sheathing,  —  and 

Asbestos  Roofing  Shingles.  —  These  are  made  of  asbestos  fiber 
and  hydraulic  cement  (as  described  in  Chapter  VII,  page  263) 
in  a  variety  of  shapes,  sizes  and  colors.  After  the  wood  sheath- 
ing has  been  covered  with  1-ply  slaters'  felt,  the  shingles  are 
nailed  on  by  means  of  copper  nails  or  clinchers  according  to  the 
" American"  method,  —  that  is,  ordinary  shingle  fashion,  —  or 
according  to  the  " French"  or  diagonal  method.  Inclines  less 
than  4  inches  per  foot  are  not  to  be  recommended. 

Asbestos  roofing  shingles  are  tough  and  yet  more  or  less  elastic, 
besides  possessing  very  considerable  fire-resistance.  An  ex- 
perimental fire  test  made  in  Boston,  1910,  of  wood  studs  and 
sheathing  covered  partially  by  wood  clapboards  and  partially  by 
asbestos  shingles,  developed  most  excellent  fire-resisting  qualities 
as  far  as  the  latter  were  concerned.  These  shingles  will  un- 
doubtedly have  a  greatly  extended  use  as  the  dangers  of  wood 
shingles  become  more  generally  realized,  and  as  the  latter  become 
prohibited  within  fire  limits,  as  is  now  the  case  in  several  cities. 

Suspended  Ceilings  under  Roofs.  —  The  general  efficiency 
of  suspended  ceilings  has  been  discussed  in  Chapter  XI,  page  343, 
and  various  forms  of  ceiling  construction  have  been  described  in 
connection  with  terra-cotta  and  concrete  floor  systems  in  Chap- 
ters XVII  and  XVIII.  Hence  ceilings  of  large  areas,  as  under 
roofs  over  entire  top  stories,  will  alone  be  considered  here,  al- 
though the  following  details  of  construction  are  equally  appli- 
cable in  many  ways  to  ceilings  suspended  beneath  floors. 

Suspended  ceilings  consist  of  light  metal  frameworks  arranged 
to  support  2-inch,  3-inch,  or  4-inch  ceiling  tile  of  terra-cotta,  or, 
more  commonly,  simply  metal  lath  and  plaster.  In  some  fire- 
resisting  buildings  the  roof  and  ceiling  have  both  been  made  of 
hollow-tile  arches,  each  of  independent  construction,  but  lighter 
than  the  floors.  This  is  not  necessary  for  either  strength,  appear- 
ance, or  efficiency.  If  the  roof  is  made  of  suitable  construction, 
with  all  supporting  members  carefully  protected,  a  suspended 


ROOFS,  SUSPENDED    CEILINGS,  FURRING 


687 


ceiling  is  all  that  is  necessary  to  fill  usual  requirements  pro- 
vided approved  methods,  as  used  by  the  best  metal-lathing  con- 
cerns, are  followed.  Too  much  skimped  work  of  this  character 
has  been  done. 

Points  requiring  special  attention  include  the  size  and  spacing 
of  the  furring  members,  —  which  should  be  made  heavier  than 
are  commonly  used,  —  the  size  and  support  of  hangers,  and  the 
attachment  of  the  metal  lath  to  the  furring.  Concerning  the 
latter  points,  Mr.  A.  L.  A.  Himmelwright  gives  the  following 
deductions  from  his  study  of  suspended  ceilings  in  the  various 
San  Francisco  buildings: 

Many  failures  of  flat  metal  lath  and  plaster  ceilings  were 
caused  by  too  light  or  poorly  designed  clips  which  supported 
the  furring  from  the  floor  beams.  Failures  also  occurred  on 
account  of  the  low  fusing  point  of  copper  wire  which  was  some- 
times employed  to  attach  the  metal  lath  to  the  furring. 

Supporting  clips  should  be  made  from  not  less  than  1-inch 
by  J-inch  steel  and  should  hook  around  both  sides  of  the  lower 
flanges  of  beams.  A  mild  steel  galvanized  lacing  wire  of  not 
less  than  No.  18  B.  &  S.  gauge  should  be  used  to  attach  the  metal 
lath  to  the  furring.* 

Where  the  ceiling  is  to  be  suspended  from  roof  beams,  a  very 
satisfactory  construction  is  shown  in  Fig.  280.  The  hangers  are 


Extension  Bar 

-  M'CS  12  cts. 


FIG.  280.  —  Suspended  Ceiling  Construction. 

spaced  4  feet  centers  and  are  made  of  1-inch  by  J-inch  bars, 
bent  over  the  lower  flanges  of  the  beams,  and  held  in  place  by 
iVinch  diameter  hooks.  If  the  hangers  are  quite  lon^,  extension 
pieces  are  used,  bolted  to  the  clamp  portion  of  the  hanger.  Flat 


*  See  "The  San  Francisco  Earthquake  and  Fire,"  published  by  the  Roebling 
Construction  Company, 


688 


FIRE    PREVENTION    AND    FIRE    PROTECTION 


bars  1J  inches  by  j\  inch,  spaced  4  feet  centers,  are  then  bolted 
to  the  hangers.  These  bars  are  perforated  at  intervals  of  12 
inches  centers  by  rectangular  holes  f-inch  by  f-inch,  through 
which  pass  small  f-inch  channels  for  the  support  of  the  metal 
lath  and  plaster.  Where  these  ceilings  are  suspended  below 
terra-cotta  arches,  toggle  bolts  are  used  for  the  support  of  the 
hangers. 

Fig.  281  shows  a  very  satisfactory  detail  for  a  suspended  ceiling 
made  of  light  tee-irons.  The  hangers,  spaced  5  feet  to  6  feet 
centers,  are  made  of  2J-inch  by  J-inch  bars,  bolted  between  two 
clamps,  which  clasp  the  lower  beam  flanges.  To  the  hangers 
are  bolted  3-inch  by  J-inch  bars,  which  are  punched  every  12 
inches  to  receive  1-inch  by  1-inch  tees,  weighing  0.87  pound  per 
foot.  '  These  receive  the  metal  lath  and  plaster,  or  if  ceiling  tile 


1  Ts  .87  Ibs. 


FIG.  281.  —  Suspended  Ceiling  Construction. 

are  desired,  a  larger  size  of  tee  may  be  used  for  the  support  of 
these  blocks.  For  the  splicing  of  the  1-inch  tees,  a  sheet-iron 
clamp,  6  inches  long,  is  wrapped  closely  about  the  tee  flanges. 
When  hammered  tight,  this  makes  a  sufficiently  rigid  splice. 

Where  concrete  roof  slabs  are  used,  the  hangers  for  suspended 
ceilings  may  be  supported  as  shown  in  Fig.  282.  Until  the  con- 
crete is  poured,  they  are  held  in  place  by  means  of  nails,  running 
through  holes  in  the  hangers,  and  resting  on  the  wood  forms. 

Specifications:  The  following  specification  for  suspended  ceiling 
construction  represents  the  best  practice: 

All  ceilings  to  be  hung  to  roof  beams  or  slabs  with  steel  hangers 
which  shall  be  1-inch  by  J-inch  when  straight,  and  2-inch  by 
J-inch  where  bending  is  required,  not  over  4  feet  on  centers  in 
either  case.  To  these  shall  be  bolted  2-inch  by  i-inch  bar  pur- 
lins, punched  to  receive  f-inch  or  1-inch  channels  which  shall  be 


ROOFS,  SUSPENDED   CEILINGS,  FURRING 


689 


placed  not  more  than  12  inches  centers  where  No.  24  gauge 
expanded  metal  is  used.  If  No.  20  wire  lath  with  No.  5  rods 
woyeri  in  is  used,  the  channels  may  be  placed  16  inches  centers. 

In  place  of  2-inch  by  J-inch  bar  purlins,  2-inch  by  2-inch  by 
J-inch  angles  may  be  used,  with  furring  channels  clamped  to 
same. 

Where  the  purlins  are  more  than  4  feet  apart,  1-inch  channels 
must  be  used. 

Metal  lath  must  be  cut  from  No.  24  gauge  sheets  and  weigh 


FIG.  282.    Suspended  Ceiling  Construction  as  used  with  Concrete  Roofs. 

at  least  3  pounds  per  square  yard.     To  be  laced  with  No.  18 
galvanized  steel  wire. 

Metal  Furring.  —  The  introduction  of  various  forms  of  metal 
lath  greatly  developed  the  use  of  metal  furring  for  wall  surfaces, 
false  ceilings,  and  the  production  of  architectural  members  in 
interior  decoration.  Very  elaborate  effects  are  now  easily  pro- 
duced by  the  aid  of  metal  furring,  lath,  and  plaster,  where  for- 
merly such  effects  were  only  possible  in  very  heavy  and  very 
expensive  construction.  Cornices,  coves,  false  beams,  arches, 
and  domes  are  readily  and  economically  constructed  with  a 
false  work  of  metal  furring,  where  previously  the  same  effects 
in  massive  construction  would  have  been  difficult,  heavy,  and 


690          FIRE    PREVENTION    AND    FIRE    PROTECTION 

expensive.  A  great  quantity  of  this  false  work  now  enters  into 
nearly  all  large  buildings,  and  the  uses  to  which  metal  furring  is 
applied  are  as  numerous  as  the  conditions  which  call  forth  its 
use.  The  furring  is  always  of  a  sham  nature,  representing  forms 
of  construction  which  do  not  exist.  It  is  never  employed  to 
carry  loads  of  any  magnitude,  —  generally  nothing  but  the 
weight  of  the  plaster  or  mosaic  finish. 

Metal  Wall  Furring  for  exterior  masonry  walls,  etc.,  usually 
consists  of  f-inch  channels  placed  horizontally  against  the  wall 
surface,  about  4  feet  centers,  with  both  flanges  turned  up.  These 
are  usually  wired  to  nails  driven  into  the  masonry.  Vertical 
1-inch  channels  or  f-inch  prong  studs  12  inches  on  centers  are 
then  wired  or  clipped  to  the  horizontal  channels.  No.  24  gauge 
expanded  metal  is  then  applied.  Or  the  vertical  supports  may 
be  placed  16  inches  on  centers  if  No.  20  wire  lath  with  No.  5 
rods  woven  in  is  used,  or  if  No.  20  wire  lath  with  1-inch  V-ribs 
woven  in  every  7i  inches  is  used. 

False  Ceilings  are  often  employed  for  architectural  effect  where 
the  ceilings  in  rooms,  hallways,  or  vestibules  are  required  to  be 
at  a  lower  level  than  the  actual  floor  construction.  False  ceilings 
are  also  employed  to  conceal  pipes  or  vents  which  may  tend  to 
disfigure  the  apartment.  Light  channels  or  angles  are  generally 
used  for  this  purpose,  spaced  about  12  inches  centers.  For 
spans  not  exceeding  5  feet,  these  may  be  run  into  the  walls  for 
support,  but  in  longer  spaces,  intermediate  hangers  are  necessary, 
as  previously  described. 

For  larger  arches  or  domed  ceilings,  structural  members  must 
be  provided  at  intervals  to  carry  the  lighter  iron  false  work. 
These  usually  consist  of  channels  or  angles  bent  or  shaped  to  the 
proper  outlines,  and  spaced  at  intervals  of  from  4  feet  to  6  feet. 
Such  members  are  placed  about  2  inches  back  from  the  finished 
plaster  line.  Light  channels  are  then  clipped  to  the  supporting 
framework  at  intervals  of  12  inches.  These  receive  the  metal 
lathing,  which  in  turn  takes  the  plaster  finish. 

Cornices,  False  Beams,  etc.,  are  made  of  brackets  formed  of 
1-inch  by  J-inch  band  iron  or  of  light  channel-iron,  spaced  not 
over  12  inches  centers,  to  which  are  fastened  longitudinal  f-inch 
channels  which  receive  No.  24  gauge  expanded  metal  or  other 
metal  lath.  The  brackets  are  bent  or  shaped  to  the  required  out- 
line, usually  at  the  building,  and  are  fastened  to  walls,  etc.,  by 
means  of  nails,  staples  or  toggle  bolts,  or  to  steel  beams  by  means 


ROOFS,  SUSPENDED    CEILINGS,  FURRING  691 


PLASTER  CORNICE 
-Expanded  Metal  Lath 

FIG.  283.  —  Cornice  and  Cove  Furring. 


of  hangers,  clips,  etc.  Fig.  283  illustrates  a  furred  cove  and 
cornice,  in  which  the  expanded  metal  lath  is  secured  directly  to 
the  band-iron  brackets. 

Metal  Lath.  —  Some  of  the  more  prominent  makes  of  ex- 
panded metal  or  metal  lath  as  used  for  ceilings,  wall  furring, 


FIG.  284.  —  Expanded  Metal  "A,"  "B"  and   "BB"  Lath. 

metal  lath  and  plaster  partitions,   false  cornices,   etc.,   are  as 
follows : 

Expanded  Metal  Lath  is  made  in  two  forms,  viz.,  the  "A,"  "B" 
and  "BB"  laths,  as  shown  in  Fig.  284, —  used  principally  for 


692 


FIRE    PREVENTION    AND    FIRE    PROTECTION 


exterior  stucco  work,  —  and  the  " Diamond"  lath,  shown  in  Fig 
285,  —  generally  used  for  ceilings,  walls,  partitions,  cornices,  etc 


FIG.  285.  —Expanded  Metal  "  Diamond  "  Lath. 


Designation. 

Gauge 
U.S. 
standard. 

Size  of 
sheets. 

Sheets 
in  a 
bundle. 

Square 
yards 
in  a 
bundle. 

Weight 
per 
square 
yard. 

A.. 

24 

Inches. 

18  X96 

9 

12 

Lbs. 

4J 

B 

27 

18  X96 

9 

12 

3 

Special  B 

27 

20^X96 

9 

13J 

2| 

Diamond  No.  24  
Diamond  No.  26 

24 
26 

22JX96 
24  X96 

9 
9 

15 
16 

3 

2f 

FIG.    286. —  "Herringbone" 
"A"    Lath. 


FIG .  287.  —  "  Herringbone ' ' 
"BB"  Lath. 


"Herringbone"  expanded  metal  lath,  so  called  from  the  shapt 
and  arrangement  of  the  meshes,  is  also  made  in  two  styles,  —  the 
"A"  lath,  shown  in  Fig.  286,  used  for  ceilings,  furring,  etc.,  — 


ROOFS,  SUSPENDED    CEILINGS,  FURRING 


693 


and  the  "BB"  lath,  shown  in  Fig.  287,  used  for  exterior  stucco 
work,  partitions,  etc. 


Designation. 

Gauge. 

Size  of 
sheets. 

Sheets  in  a 
bundle. 

Square 
yards  in  a 
bundle. 

Weight  per 
square 
yard. 

"BB" 

27 

Inches. 

20iX96 

15 

22J 

Lbs. 

2i 

"BB" 

26 

20JX96 

15 

22i 

2£ 

"BB" 

24 

20iX96 

15 

22J 

31 

"A" 

28 

14  X96 

20 

20 

3 

Kuhne's  Clincher  Lath,  made  of  indented  and  perforated  sheet 
metal,  has  been  successfully  used  for  ceilings,  wall  furring  and 
other  flat  surface  work.  The  sheets  are  13 J  inches  by  96  inches 
in  size,  being  shipped  in  bundles  of  10  sheets. 


PAET   V 

SPECIAL   STRUCTURES   AND  FEATURES 


CHAPTER  XXII. 
THEATRES. 

THE  theory  and  practice  of  fire  prevention  and  fire  protection 
as  applied  to  theatres  is  too  large  and  too  important  a  subject 
to  be  adequately  treated  within  the  confines  of  a  single  chapter. 
Volumes  could  be  and  have  been  written  on  the  subject,  among 
which  may  be  mentioned  Mr.  Edwin  O.  Sachs'  "  Modern  Opera 
Houses  and  Theatres,"  in  three  large  volumes,  including  three 
supplements,  with  20  plates  and  860  illustrations,  1897,  —  Mr. 
William  Paul  Gerhard's  "  Theatres,  their  Safety  from  Fire  and 
Panic,  their  Comfort  and  Healthfulness,"  1900,  —  and  Mr. 
John  R.  Freeman's  "On  the  Safeguarding  of  Life  in  Theatres." 
Also  a  proposed  standard  ordinance  of  great  value  covering 
"Theatre  Construction  and  Equipment,"  representing  the  best 
present-day  thought  on  these  subjects,  has  been  prepared,  after 
long  investigations,  by  a  special  committee  of  the  National  Fire 
Protection  Association  in  conjunction  with  a  special  committee 
of  the  American  Institute  of  Architects  and  other  experts.* 

To  these,  reference  may  be  made  for  a  more  complete  study 
of  theatre  design  and  construction.  However,  most  of  the  really 
vital  points  in  fire  prevention  and  fire  protection  in  theatres  may 
be  touched  on  within  the  limits  of  a  Handbook  chapter,  and  as 
many  decided  improvements  in  such  matters  have  taken  place 
within  the  last  few  years,  especially  in  American  theatres,  it  is 
hoped  that  the  following  discussion  may  be  of  value,  even  to  those 
having  considerable  knowledge  of  the  subject.  Perhaps  no  one 
theatre  or  opera  house  yet  built  may  combine  all  of  the  recom- 
mendations herein  set  forth,  —  and  yet  a  constantly  increasing 
number  of  our  new  American  theatres  is  incorporating  more  and 
more  of  these  vital  principles  of  design. 

Statistics  of  Theatre  Fires.  —  Mr.  Edwin  O.  Sachs,  in  his 
monograph  previously  mentioned,  tabulates  no  less  than  1,115 

*  See  "1911  Proceedings  of  National  Fire  Protection  Association."  As  many 
extracts  will  be  given  from  this  report  in  the  present  chapter,  such  quotations 
will  be  designated  by  the  reference  sign  §. 

697 


698         FIRE   PREVENTION   AND   FIRE   PROTECTION 

fires,  occurring  previously  to  December  31,  1896,  which  either 
materially  or  wholly  damaged  theatre  buildings.  The  cause  and 
location  of  the  outbreak  of  fire  are  given  in  all  possible  cases. 
While  interesting,  and  valuable  in  some  respects,  such  statistics 
are  not  applicable  to  present-day  conditions  for  the  reasons  that 
most  theatres  which  have  heretofore  been  destroyed  by  fire  were 
built  without  any  particular  knowledge  or  care  as  to  either  fire 
prevention  or  fire  protection,  and  were  lighted  by  gas. 

Loss  of  Life.  —  Fires  in  theatres  or  other  places  of  amusement 
involving  great  loss  of  life  have  been  numerous  in  nearly  all 
civilized  countries.  Among  the  more  notable  may  be  mentioned: 

The  Brooklyn  Theatre  fire,  1876,  in  which  293  people  were 
killed,  all  in  the  upper  gallery.  The  cause  was  a  "border" 
catching  fire  from  gas  border  lights. 

The  Ring  Theatre  fire,  Vienna,  Austria,  1881 .  Of  an  audience 
of  1,800,  450  were  killed,  mostly  in  the  upper  gallery.  The  cause 
was  the  ignition  of  scenery  through  careless  lighting. 

A  theatre  fire  in  Exeter,  England,  1887,  resulted  in  the  death 
of  200  persons  within  a  few  minutes  after  the  outbreak,  again 
mostly  in  the  upper  gallery. 

The  Iroquois  Theatre  fire,  Chicago,  December  30,  1903,  which 
resulted  in  the  loss  of  566  lives,  has  been  previously  described  in 
Chapter  VI. 

Deductions  from  Statistics. — Notwithstanding  the  greatly 
changed  conditions  as  to  construction,  lighting,  and  equipment, 
etc.,  in  modern  theatres  of  the  better  class,  certain  deductions 
of  great  value  may  be  drawn  from  the  records  of  past  fires, 
as  follows : 

1.  That  theatres  as  a  class  constitute  dangerous  risks. 

2.  That  the  causes  of  theatre  fires  are  usually  attributable  to 
either  carelessness  or  defects.     They  should  be  decreasingly  less, 
owing  to  improvements  made  in  lighting,  heating,  etc.;  but  a 
large  hazard  still  exists. 

3.  That  the  stage  constitutes  the  most  dangerous  feature. 
It  has  been  estimated  by  Mr.  Freeman  that  the  total  weight 

of  combustible  material  on  the  stage  of  the  Iroquois  Theatre 
amounted  to  more  than  10  tons. 

It  is  a  very  rare  case  that  so  much  scenery  is  found  upon  a 
stage,  but  if,  as  is  more  common,  it  were  only  one-fourth  part  as 
much,  it  is  plain  that  the  fuel  supply  is  sufficient  to  send  out  an 
enormous  volume  of  suffocating  gas,  Indeed,  I  have  computed 


THEATRES  699 

that  merely  the  quick  burning  of  the  160  pounds  of  gauze  that 
hung  over  the  Iroquois  stage  would  heat  a  volume  of  air  equal  to 
that  contained  in  the  space  above  the  proscenium  arch  to  1000°F. 

4.  That  the  galleries  comprise  the  locations  most  dangerous 
to  the  audience.     The  theatre  fires  before  mentioned  show  this 
conclusively. 

5.  That,  in  theatre  design  and  management,  life-safety  should 
be  of  the  first  importance.     The  repetition  of  history  in  dis- 
astrous fires,  coupled  with  an  extended  present-day  knowledge 
of  theatre  design,  equipment  and  construction,  leaves  no  excuse 
for  the  shirking  of  responsibility  by  theatre  owners  or  managers. 

Requisites  for  Safety.  —  No  less  an  authority  than  Mr.  Ed- 
win O.  Sachs  has  stated  that  theatre  safety  really  means  the 
safety  of  the  human  lives  in  a  theatre,  and  not  the  safety  of 
property.  Hence,  at  the  Amsterdam  Fire  Congress  of  1896,  he 
suggested  that  theatre  planning  be  given  primary  considera- 
tion, as  distinct  from  construction;  and  that  the  requisites  for 
theatre  safety  be  always  considered  in  the  following  order  of 
importance,  —  (1)  planning,  (2)  watching,  or  vigilance  during 
performances,  (3)  inspection,  (4)  construction.  Mr.  Wm.  Paul 
Gerhard  follows  the  same  order  of  importance  in  his  authoritative 
discussions  of  theatre  safety. 

Planning,  as  stated  above,  is  the  most  important  considera- 
tion looking  to  safety  of  life  in  theatres,  provided  it  includes  all 
questions  pertaining  to  equipment,  safety  appliances,  etc. 

In  Chapter  IX  it  was  stated  that  adequate  fire-resisting  design 
comprises  planning,  construction,  and  equipment,  where  build- 
ing and  contents  are  of  equal  importance;  but  in  theatres  and 
similar  public  buildings,  where  the  safety  of  human  lives  is  of 
paramount  importance,  the  equipment  must  be  considered  as 
an  integral  part  of  the  plan. 

Planning,  in  the  sense  here  intended,  involves  the  general 
location  and  particular  site,  —  the  plan  or  arrangement  of  the 
building,  —  and  all  features  of  prevention  and  equipment  which 
enter  into  the  building  design, — as  contrasted  with  questions 
involving  only  materials  or  methods  of  pure  construction. 

Another  reason  why  stress  will  not  be  laid  upon  fire-resist- 
ing construction  is  that  incombustible  or  fireproof  construction, 
per  se,  cannot,  and  does  not,  absolutely  prevent  theatre  fire  dis- 
asters. For  instance,  an  ill-planned  theatre,  having  its  exits 
badly  arranged  or  insufficient  in  number,  may,  in  case  of  a  real 


700         FIRE    PREVENTION    AND   'FIRE    PROTECTION 

or  false  alarm  of  fire,  prove  a  veritable  death  trap,  though  its 
construction  may  be  thoroughly  fireproof;  and,  vice  versa,  a 
theatre  which  is  combustible,  which  has  wooden  staircases,  and 
which  lacks  fire  extinguishing  appliances,  may  yet  be  so  planned 
and  arranged  as  to  afford  the  public  perfect  means  for  quick 
escape  from  smoke  and  fire,  and  therefore  be  the  safer  of  the  two. 
This  instance  indicates  clearly  that  there  are  other  safety  meas- 
ures of  much  more  importance  than  fire-resisting  construction.* 

Location  and  Site.  —  As  to  location,  consideration  should  be 
given  the  general  neighborhood  proposed,  and,  particularly,  the 
hazards  of  adjacent  properties.  The  location  should  avoid 
proximity  to  dangerous  risks,  such  as  piano  factories,  manu- 
factories involving  especially  hazardous  processes,  or  buildings 
liable  to  contain  large  quantities  of  highly  combustible  material, 
such  as  stables,  etc.  Even  small  fires  in  such  neighboring 
properties,  especially  if  producing  much  smoke,  may  lead  to 
serious  panic  on  the  part  of  an  audience  quite  as  readily  as  a  fire 
within  the  theatre  structure. 

As  to  site,  this  should  be  as  open  as  possible,  preferably  front- 
ing on  streets  on  all  four  sides.  This  is  not  usual  in  this  country, 
but  in  some  continental  cities  it  is  required  by  law.  An  example 
of  an  entirely  detached  theatre  is  the  new  Stadt-Theatre,  Berne, 
Switzerland,  which  faces  on  a  prominent  open  square,  with  open 
streets  on  the  other  three  sides. 

In  London  the  site  for  a  new  theatre  or  music-hall  must 
abut  for  one-half  of  the  boundary  upon  public  thoroughfares,  one 
of  which  must  be  not  less  than  forty  feet  wide.  This  is  exactly 
one-half  of  the  requirement  as  to  site  in  most  continental  cities, 
where,  as  in  Manchester,  England,  the  theatre  must  be  entirely 
isolated.  .  .  .  We  are  now  actually  getting  isolated  theatres, 
whereas  a  few  years  ago  there  was  not  one  in  London. f 

In  this  country,  theatres  usually  have  but  one  street  front,  but 
in  the  better  examples  of  recent  practice  where  a  theatre  is  located 
between  adjacent  structures,  open  courts  are  provided  on  the 
sides,  into  which  stage-  and  auditorium-exits  may  empty.  The 
position  and  size  of  such  courts  are  usually  covered  by  ordinance 
in  the  larger  cities,  as  is  further  explained  under  a  later  para- 
graph "  Courts." 

*  See  "The  Safety  of  Theatre  Audiences  and  the  Stage  Personnel  against 
Danger  from  Fire  and  Panic,"  by  Wm.  Paul  Gerhard. 

t  "Lessons  from  Fire  and  Panic,"  by  Thos.  Blashiil.  See  British  Fire 
Prevention  Committee's  "Red  Book"  No,  9. 


THEATRES  701 

Mr.  John  R.  Freeman  considers  that  proper  planning  is  far 
more  essential  than  mere  location. 

"It  is  worthy  of  note  that  it  is  not  essential  for  safety  that  a 
theatre  should  stand  in  an  open  lot.  Some  of  the  worst  theatre  fires 
in  history  have  happened  where  the  space  around  the  theatre  was 
open  on  three  sides  or  four  sides.  It  is  far  more  important  that 
attention  be  given  to  the  detail  of  fire  walls  and  to  providing  safe 
passageways."* 

The  Plan  or  Arrangement  should,  as  previously  stated,  in- 
clude not  only  the  sub-division  of  areas,  but  all  questions  in- 
volving equipment,  safety  appliances,  etc.,  as  well.  Effective 
planning  should  therefore  include  a  most  thorough  consideration 
of  the  isolation  of  dangerous  risks,  exits,  the  stage  and  its  ap- 
purtenances, fire  curtains,  safety  appliances  and  other  preventive 
safeguards  upon  the  stage,  and  fire-detecting  and  fire-extinguish- 
ing equipment  throughout  the  building. 

Isolation  of  Dangerous  Risks. — Boiler  rooms,  metre  closets, 
paint-  and  carpenter-shops,  property-,  costume-,  and  storage- 
rooms  should  all  preferably  be  separated  from  the  stage  portion 
of  building  by  means  of  brick  walls  and  adequate  fire  doors. 
A  most  admirable  arrangement  of  such  dangerous  features  is 
provided  in  the  new  Boston  Opera  House,  Wheelwright  and 
Haven,  Architects,  as  illustrated  in  Fig.  288. 

No  workshop,  storage  or  general  property  room  shall  be 
allowed  in  or  under  the  auditorium,  above  the  stage  or  under  the 
same,  or  in  any  of  the  fly  galleries,  but  such  rooms  or  shops  may 
be  located  in  the  rear  of,  or  at  the  side  of  the  stage,  and  in  such 
cases  they  shall  be  separated  from  the  stage  vertically  and  hori- 
zontally by  a  brick  or  concrete  wall  not  less  than  twelve  inches  in 
thickness  or  other  equally  efficient  cut-off,  and  the  openings  lead- 
ing into  said  portion  shall  have  self-closing  fire  doors  on  one  side 
of  the  wall  and  standard  automatic  fire  doors  on  the  other  side 
of  the  wall. 

No  sleeping  accommodations  shall  be  allowed  in  any  part 
of  the  building  communicating  with  the  auditorium  or  stage.  § 

Exits. f  —  The  importance  of  adequate  means  of  exit  from 
theatres  is  summed  up  by  Mr.  Sachs  as  follows: 

"Everything  to  insure  good  exits  should  be  done,  even  if 
some  of  the  other  requirements  of  modern  theatre  construction 

*  See  "On  the  Safeguarding  of  Life  in  Theatres." 

t  For  an  extended  discussion,  see  "Theatre  E^its"  by  Mr.  Alfred  Darby- 
shire,  British  Fire  Prevention  Committee's  "Red  Book"  No.  4. 


702 


FIRE    PREVENTION    AND    FIRE    PROTECTION 


FIG. 


IE.D.  fcJT 

8.  —  Plan  of  Boston  Opera  House. 


TOT 


have  to  be  given  a  second  place.  As  far  as  the  audience  is  con- 
cerned, suitable  exits  and  straightforward  planning  should  be 
given  preference." 

Mr.  Blashill  has  even  more  forcibly  described  the  necessity  for 
adequate  exits:  "I  have  advised  a  theatre  architect  to  begin  by 
laying  down  on  his  plan  eight  staircases  and  ten  or  twelve  exit 
doors,  and  then  see  whether  he  had  room  left  for  a  stage  and 
auditorium.  This  is  more  reasonable  than  planning  first  these 
last-named  parts,  and  then  using  up  any  spare  corners  for  scanty 
and  inconvenient  stairs  and  passages."* 

*  "Red  Book,"  No.  9. 


THEATRES  703 

The  study  of  " exits"  includes  the  sub-division  of  the  audi- 
torium into  tiers,  with  the  quick  emptying  thereof,  —  adequate 
means  of  egress  for  all  employees  in  stage  portion,  etc.,  —  the 
size  and  placing  of  seats,  —  aisles,  —  foyers  and  lobbies,  — 
courts,  —  stairs  and  other  means  of  egress,  —  fire  escapes,  — 
doors  and  door  fastenings,  etc.,  —  and  lighting.  "In  other  words 
the  term  '  exit '  includes  the  entire  road  which  a  spectator,  seated 
in  the  audience,  has  to  travel  in  order  to  reach  the  open  air." 

Tiers.  —  The  problem  of  how  to  secure  the  quick  and  safe 
departure  of  a  theatre  audience  is  largely  a  question  of  its  proper 
and  sufficient  sub-division.  While  this  is,  to  some  extent,  secured, 
a  priori,  by  the  division  into  different  tiers,  this  in  itself  would  not 
be  sufficient,  particularly  if  exits  from  different  tiers  are  made 
to  lead  into  a  common  lobby.  Each  section  should  be  again 
divided  and  made  to  leave  by  several  independent  outlets.* 

The  usual  arrangement  of  tiers  in  this  country  includes  a 
parquet,  a  balcony,  and  a  gallery,  each  of  which  divisions  should 
have  not  less  than  two  independent  means  of  exit.  In  large 
heatres  or  opera  houses,  even  more  than  two  means  of  exit  may 
necessary  for  each  tier.  All  of  these  exit  passages  should  be 
ndependent,  from  their  source  in  the  auditorium  to  the  open  air, 
and  "should,  under  no  circumstances  whatever,  cross  each  other, 
meet  or  be  combined."! 

The  Main  Floor,  or  parquet,  is  usually  placed  at  the  street  level, 
>ref  erably  without  steps.  The  sunken  "  pit "  so  common  to  English 
heatres  is  not  used  in  this  country,  nor  in  Continental  theatres, 
iit  an  arrangement  somewhat  similar  to  a  "pit"  is  used  in  the 
"orest  Theatre,  Philadelphia,  where  inclined  planes  at  equal  gradi- 
ents lead  from  the  street  or  lobby  level  down  Balcony 
o  the  parquet  and  up  to  the  balcony,  thus:  Lobby  / 
This  arrangement  is  commendable  in  that  it  \  Parquet 
'educes  the  height  of  both  balcony  and  gallery  above  the  street, 
hus  shortening  the  lines  of  travel. 

The  Balcony,  in  most  cases,  does  not  present  any  particular 
difficulties  as  to  quick  emptying.  It  is  generally  possible,  except 
when  planning  within  most  circumscribed  conditions,  to  provide 
it  least  one  straight  exit  way  from  balcony  to  street,  without 
:urn. 

The  Gallery  is  both  the  most  dangerous  portion  of  the  audi- 
torium and  the  most  remote  from  the  street.  The  gallery 

*  Gerhard.  t  Ibid. 


704         FIRE    PREVENTION   AND   FIRE   PROTECTION 

audience  should  therefore  be  given  every  possible  means  of  simple, 
direct,  and  adequate  egress.  Mr.  Freeman  advises  that  the  area, 
the  total  number  of  stairway  exits,  and  the  total  width  of  stair- 
way per  hundred  persons  be  made  two  or  three  times  as  great  for 
the  gallery  as  for  the  other  parts  of  the  house,  pointing  out,  also, 
that  the  width  of  stairways,  as  emphasized  by  most  building  laws, 
is  not  the  sole  consideration.  Thus  the  architect  of  the  Iroquois 
Theatre  testified  that  the  gallery  exits  of  that  theatre  were  of 
100  per  cent,  greater  total  width  than  the  law  required.  Yet 
70  per  cent,  of  those  in  the  Iroquois  gallery  perished,  principally 
due  to  locked  doors  at  fire  escapes,  to  a  blind  passageway  wherein 
many  were  suffocated,  and  to  generally  inaccessible  means  of  exit. 

Thus  the  gallery,  especially,  requires  frequent  and  accessible 
as  well  as  ample  means  of  egress,  and  this  has  been  obtained  in 
many  late  examples  of  theatre  design  partly  by  means  of  "  vomi- 
tories," or  short  flights  of  steps  leading  from  intermediate  aisles 
in  the  gallery,  —  and  sometimes,  though  less  frequently,  in  the 
balcony,  —  down  to  a  transverse  passageway  or  tunnel  which 
runs  under  the  gallery  and  which  discharges  into  stairs  at  either 
one  or  both  ends.  Such  vomitories  are  shown  in  plan  in  Fig.  291, 
and  in  section  in  Fig.  292.  The  use  of  vomitories  greatly  helps 
the  centralization  and  the  proper  distribution  of  exits,  especially 
in  long  balconies  or  galleries,  thus  promoting  quick  emptying. 
An  objection  to  their  use  lies  in  the  fact  that  the  people  using 
them  have  to  go  down  steps  leading  directly  from  aisles.  Such 
steps  are  always  less  safe  than  steps  leading  up,  either  in  or  from 
an  aisle,  as  experience  shows  that  people  are  less  prepared, 
especially  in  a  dim  light,  for  steps  leading  down,  which  are  not 
plainly  seen. 

In  the  ordinance  proposed  by  the  National  Fire  Protection 
Association,  the  use  of  vomitories  is  covered  as  follows: 

There  shall  be  no  more  than  eleven  feet  rise,  measured  ver- 
tically, in  any  aisle  in  any  gallery  without  direct  exit  by  tunne 
or  otherwise,  to  a  corridor  or  passage  with  a  free  opening  on  tc 
the  gallery  stairs  or  other  direct  discharge  to  the  street.  At  such 
elevation  of  eleven  feet  or  less  an  intervening  or  cross  aisle  leading 
directly  to  an  exit  may  be  substituted  for  the  tunnel.  No  suet 
tunnel  or  cross  aisle  shall  be  less  than  four  feet  wide  in  the  clear. 

Quick  Emptying  Tests. —  Numerous  tests  have  been  made 
of  the  time  required  to  empty  theatre  buildings  of  their  audiences 
under  both  normal  and  test  conditions.  Mr.  Gerhard  quotes  £ 


THEATRES  705 

number  of  examples  of  New  York  and  Continental  theatres,  all 
showing  from  two  to  four  minutes  as  the  actual  emptying  time. 
After  careful  observations  in  representative  Chicago  theatres, 
Mr.  Freeman  found  that  all  corridors  were  generally  cleared  in 
from  three  and  one-half  to  five  minutes  after  the  drop  of  the 
curtain,  and  that,  ordinarily,  from  two  to  three  minutes  sufficed 
for  the  clearing  of  both  balcony  and  gallery.  However,  the  time 
consumed  in  the  leisurely  emptying  of  an  auditorium  is  not  a 
safe  guide  for  the  quick  emptying  under  panic  conditions. 
People  were  struggling  at  exits  of  the  Iroquois  Theatre  as  late  as 
nine  minutes  after  the  alarm  was  turned  in. 

Mr.   Gerhard  strongly  recommends  actual  test  of  the  time 

required  to  empty  any  theatre  building,  while  Mr.  H.  F.  J.  Porter, 

who  has  had  wide  experience  in  organizing  fire  drills  in  factories, 

etc.,  and  who  has  studied  especially  the  handling  of  crowds  in 

•uildings,  recommends  that,  in  the  case  of  any  building  con- 

aining  many  people,  a  rapid  egress  test  be  made  obligatory  before 

he  building  is  accepted  as  safe  by  the  municipal  authorities. 

See,  also,  Chapter  XXXVII. 

In  view  of  the  above,  the  following  calculations  regarding 
rieans  of  exit  are  of  particular  interest: 

ENTRANCES  AND  EXITS  —  DEFINITION. 

The  term  'exit'  as  used  in  this  section  refers  to  emergency 
ixits  only;  the  term  'entrance'  refers  to  all  other  traffic  ingress  or 
egress. 

CALCULATIONS. 

The  combined  width  of  entrances  and  exits  for  each  tier,  like- 
wise their  stairs,  shall  provide  one  foot  of  width  for  each  20  per- 
ons  to  be  accommodated  in  that  tier.* 

The  width  of  entrance  stairs  shall  be  at  least  50  per  cent,  of 
he  combined  width  of  the  entrance  and  exit  stairs  and  for  further 

*  A  large  number  of  actual  counts  made  by  reliable  authorities  (see  paper 
ntitled  "A  Terminal  Station"  presented  by  Messrs.  J.  Vipond  Davis  and 
.  Hollis  Wells  before  the  American  Institute  of  Architects  at  Washington, 
).  C.,  December,  1909)  show  that,  with  freely  moving  crowds  going  in  one 
irection,  an  average  of  thirteen  (13)  people  per  foot  of  width  per  minute  will 
>ass  down  a  stairway.  This  figure  was  accordingly  selected  as  the  basis  for 
stimating  the  combined  width  of  entrance  and  exit  stairs,  allowing  a  period 
f  two  minutes  in  which  to  empty  each  tier. 

Considering  the  probability  of  unfavorable  conditions  due  to  a  panic  or  other 
auses,  the  width  of  entrance  and  exit  stairs  is  figured  on  the  assumption  that 
wo-thirds  of  the  audience  may  pass  out  at  either  side  of  the  auditorium. 

The  calculation  under  the  above  conditions  for  determining  the  necessary 


706         FIRE    PREVENTION    AND    FIRE    PROTECTION 

safety  the  aggregate  width  of  exit  doorways  opening  from  each 
gallery  shall  be  60  per  cent,  more  than  the  open  air  stairs  to  which 
they  lead. 

ENTRANCES. 

A  common  place  of  entrance  may  serve  for  the  orchestra 
floor  of  the  auditorium  and  the  first  gallery,  provided  such  en- 
trance and  the  passages  leading  thereto  are  of  the  width  required 
for  the  aggregate  capacity  of  these  two  tiers. 

Separate  places  of  entrance  shall  be  provided  for  each 
gallery  above  the  first. 

EXITS  —  MINIMUM  AND  FIRE  DOORS  FOR. 

From  the  auditorium  at  least  two  exits  remote  from  each 
other  leading  into  open  courts  or  streets  shall  be  provided  in  each 
of  both  side  walls  of  the  auditorium  on  all  tiers.  Each  exit  shall 
be  provided  with  approved  fire  doors. 

In  buildings  used  for  motion  picture  shows  and  having  no 
stage,  the  required  exits  and  court  at  one  side  may  be  replaced  by 
equivalent  exits  and  court  at  the  rear  if  consistent  with  the  ade- 
quate distribution  of  the  entire  entrance  and  exit  facilities.  § 

v 

Illustrations  of  Safe  Exits. — Figures  289  to  294  inclusive* 
were  prepared  by  Mr.  John  R.  Freeman  to  demonstrate  the  pos- 
sibility of  planning  safe  exits  within  the  limitations  presented 
by  a  laterally  bounded  site.  Regarding  these,  Mr.  Freeman 
states  as  follows: 

In  the  preparation  of  these  plans  I  had  it  in  mind  to  enter 
a  protest  against  some  of  the  requirements  which  have  been 

total  width  for  entrance  and  exit  stairways,  for  any  specified  number  of  people 
such  as  500,  would  have  this  form:  — 

\X  5™  X  2,  or  in  reduced  form  500  -H  19.5. 
2  X  1« 

For  further  simplification,  the  derived  number  is  assumed  as  20  instead  of 
the  actual  19.5.  This  will  give  stairs  but  slightly  narrower  than  those  which 
would  be  obtained  by  applying  the  iormula  in  detail,  and  makes  the  calculation 
extremely  simple. 

It  is  further  specified  that  the  width  of  the  entrance  stairs  shall  be  at  least 
fifty  per  cent,  of  the  total  stairway  capacity  provided  by  this  calculation. 

To  encourage  the  audience  to  divide  and  thus  offset  in  part  at  least  the  in- 
stinctive tendency  to  escape  by  way  of  the  most  familiar  entrance,  the  aggregate 
width  of  exit  doorways  opening  from  each  tier  shall  be  at  least  60  per  cent,  widei 
than  the  open  air  stairs  to  which  they  lead;  persons  after  reaching  the  outside 
stairs  and  balconies  required  in  this  ordinance  are  comparatively  safe  whec 
they  have  passed  beyond  the  exit  doorways  opening  from  the  tier  under  con- 
sideration. 

Attention  is  also  called  to  the  minimum  requirements  for  both  stairway* 
and  doorways jwhich  must  always  obtain. 

*  Reproduced  by  permission  from  Mr.  John  R.  Freeman's  "On  the  Safe 
guarding  of  Life  in  Theatres." 


THEATRES  707 

urged  by  eminent  authorities  as  essential  to  the  safety  of  the  audi- 
ence, such,  for  example,  as  that  frequently  urged  in  Europe,  that 
a  large  theatre  or  house  of  public  entertainment  ought  to  stand 
in  an  open  lot,  and  as  a  means  of  showing  that  such  arrangements 
for  safety  as  proposed  by  the  late  Sir  Henr.y  Irving  in  his  designs 
for  a  modern  theatre  were  unnecessary. 

I  therefore  purposely  assumed  the  difficulties  of  a  site  in 
the  middle  of  a  block,  closely  built  up  against  on  either  side  and 
open  only  front  and  rear  and  to  the  sky  above.  To  make  the 
illustration  more  complete,  I  also  assumed  a  minimum  width  of 
site.  The  purpose  is  to  show  that  the  fundamental  requirements 
for  safety  of  the  audience  and  safety  of  the  fire  underwriter's 
risk  can  all  be  adequately  met  on  almost  any  kind  of  site,  and 
that  it  is  not  difficult  to  provide  far  more  safe  and  generous  exit 
than  is  often  found. 

The  drawings  set  forth   the  proposed   means  of  providing 
several  exits  so  clearly  that  little  description  is  necessary.     The  , 
total  seating  capacity  is  about  1500,  a  large  house.     The  points 
of  chief  interest  are: 

1st.  —  The  ample  exit  in  four  different  directions  from  the 

balcony  and  the  gallery.     I  would  call  particular  attention  to 

the  exits  at  the  front  corners,  which  have  a  special  value  in  being 

Iways  in  sight  and  in  front  of  the  sitter;  these  will  tend  to  relieve 

he  crush  toward  the  rear. 

2nd.  —  The  use  of  a  tower  fire  escape  (in  the  rear  at  the  left) 
nodeled  on  the  line  of  the  Philadelphia  factory  fire  escape,  com- 
nunicating  with  the  open  air  and  with  no  door  from  auditorium 
r  stage  or  dressing  room  opening  directly  into  the  stair  tower 
>roper;  it  being  required  that  passage  be  made  from  the  audi- 
orium  out  across  a  platform,  freely  open  to  the  air,  before  the 
stairway  can  be  entered.  This  arrangement  makes  it  almost 
ertain  that  the  stairway  will  always  be  free  from  smoke. 

3rd.  —  Note  that  the  stairway  exits  from  gallery  nearest  the 
treet  are  entirely  separate  from  exits  from  other  floors  and  serve 
be  gallery  only.  To  still  further  favor  rapid  exit  from  the  gal- 
ery,  two  additional  exits  *  from  the  middle  portion  of  the  seating 
pace  drop  to  a  corridor  below,  making  six  exits  in  all,  and  these 
o  scattered  that  choking  about  their  entrances  would  appear 
mpossible.  As  a  means  of  separating  the  gallery  exit  from  that 
f  the  balcony,  I  have  in  the  spiral  layout  of  the  stairs  employed 
novel  device  analogous  to  a  double-threaded  screw. 

4th.  —  It  will  also  be  noted  that  in  view  of  the  enclosed 
ituation  two  ample  exits  of  large  size  have  been  provided  to  the 
lley  in  the  rear,  for  both  audience  and  stage  people,  each  being 
sort  of  fireproof  tunnel. 

5th.  —  It  will  also  be  noted  that  provision  has  been  made  for 
)ermitting  daylight  to  enter  the  auditorium  and  stage  space,  but 
hat  the  windows  can  be  closed  and  daylight  excluded  while  an 
iternoon  performance  is  in  progress.  These  windows  should  be 
;lazed  with  prism  glass  for  better  diffusion  of  light  if  the  open-air 
ourt  is  narrow. 

*  Vomitories. 


Alley  Side 
-80- 


Windows  18  Squai 
'Polished  Wire  Glass  in 
^ Cast  Iron  Frame 


Floor  of  Lower  Tier 

of.Dressing  Roon 

is  4  above  Stage 


Main  Street 
FIG.  289.  —  Main  Floor  Plan,  Model  Theatre  Design. 


THEATRES 


709 


Broad  Alley 


FIG.  290.  —  Balcony  Plan,  Model  Theatre  Design 


710          FIRE    PREVENTION    AND    FIRE    PROTECTION 

Broad  Alley  ||Fire  Escape 


Motive-Ratyd  Exit 
400  Chjairs        ; 
Six  Independent  Exits 
with  Total  \yidth  of  30' 
No  person  has  {o  pass  more 
than  3  seats  in  reaching  Aisl 


STREET 


Fia.  291.  —  Gallery  Plan,  Model  Theatre  Design. 


THEATRES 


711 


712         FIRE   PREVENTION   AND   FIRE   PROTECTION 


THEATRES 


713 


714 


FIRE    PREVENTION    AND    FIRE    PROTECTION 


Seats.  —  The  width  of  individual  seats  is  more  a  matter  of 
comfort  than  of  safety.  The  distance  back  to  back  of  seats,  how- 
ever, is  a  matter  of  vital  importance,  as  this  largely  determines 
the  aisle  space  between  seats.  This  dimension  measured  in  a 
horizontal  direction  is  usually  fixed  by  law.  The  Boston  building 
law  requires  thirty  inches  as  a  minimum,  and  the  New  York  law 
thirty-two  inches,  for  all  seats  in  auditorium  except  those  in 
boxes. 

Both  the  New  York  and  Boston  building  laws  require  that 
not  more  than  fourteen  seats  shall  occur  in  any  one  row,  or  six 
on  each  side  of  the  central  two  seats.  The  National  Fire  Pro- 
tection Association's  proposed  standard  ordinance  requires  that 
no  gallery  seat  shall  have  more  than  four  seats  intervening  be- 
tween it  and  an  aisle,  or  more  than  ten  seats  in  a  row  between 
any  two  aisles. 

Aisles.  —  A  brief  comparison  of  requirements  is  as  follows : 


N.  Y.  law. 

Boston. 

N.  F.  P.  A. 
Ordinance. 

Aisles  having  seats  on  both  sides, 
min.  width  . 

36  ins 

30  ins 

36  ins 

Aisles  having  seats  on  both  sides, 
increase  toward  exits,  per  5 
feet  

\~  ins. 

1  in 

1^  ins 

Aisles  having  seats  on  one  side, 
min.  width 

36  ins 

24  ins 

42  ins 

Aisles  having  seats  [on  one  side, 
increase  toward  exits,  per  5 
feet. 

1^  ins 

1  in 

1^  ins 

All  authorities  agree  that  it  is  desirable  to  increase  the  width 
of  aisles  toward  the  exits.  Mr.  Freeman  states  that,  in  his 
opinion, 

the  width  of  the  aisles  near  the  stage  might  reasonably,  and 
with  advantage,  be  made  much  narrower  than  the  law  now  per- 
mits, thus  increasing  the  number  of  good  seats,  and  the  earning 
capacity  of  the  house  enough  to  pay  good  interest  on  the  cost  of 
making  it  safer  and  providing  more  numerous  aisles,  exits  and 
stairways  at  the  rear.  ...  It  is  far  better  to  introduce  addi- 
tional aisles  at  the  expense  of  making  all  the  aisles  narrower. 

In  the  requirements  of  the  standard  code  of  the  National  Fire 
Protection  Association  given  above,  it  will  be  noted  that  side 


THEATRES  715 

aisles  are  made  wider  than  intermediate  ones.  This  is  because 
people  naturally  congregate  at  the  sides  in  reaching  exits,  and 
especially  emergency  exits,  which  usually  lead  from  the  side  walls. 

Steps  in  Aisles. 

Steps  in  aisles  shall  be  the  full  width  of  the  aisle.  No  risers 
shall  be  more  than  9  inches  in  height,  and  no  tread  shall  be  less 
than  10  inches  in  width,  and  whenever  the  rise  of  seat  platforms 
is  4  inches  or  less,  the  floor  of  the  aisles  shall  be  made  as  a  gradient. 
Where  steps  are  placed  in  passages  they  shall  be  grouped  together 
and  shall  be  clearly  lighted.  No  stool,  seat  or  other  obstruction 
shall  be  placed  in  any  aisle.  § 

Mr.  Gerhard  advises  that  aisles  should  always  be  planned 
with  gradients  or  inclines  instead  of  steps.  This  is  usually  very 
difficult  of  accomplishment. 

Passages.  — 

The  width  of  passages  and  hallways  shall  be  computed  in 
the  same  manner  as  provided  for  stairways,  but  no  passage  may 
be  less  than  5  feet  in  width.§ 

Foyers,  Lobbies,  etc.  — 

According  to  the  New  York  law,  "the  foyers,  lobbies,  corri- 
dors, passages  and  rooms  for  the  use  of  the  audience,  not  including 
aisles,  shall  on  the  first  or  main  floor,  where  the  seating  capacity 
exceeds  500,  be  at  least  16  feet  clear,  back  of  the  last  row  of  seats; 
and  on  each  balcony  or  gallery,  at  least  12  feet  clear  of  the  last 
row  of  seats." 

The  Boston  law  requires  the  aggregate  capacity  of  all  such 
royers,  lobbies,  etc.,  on  each  tier  to  be  sufficient  to  contain  the 
whole  number  of  persons  to  be  accommodated  on  such  tier,  in  the 
ratio  of  one  square  foot  of  floor  room  per  person.  In  the  opinion 
of  Mr.  C.  H.  Blackall,  who  has  probably  designed  more  theatres 
than  any  other  American  architect,  and  who  was  a  member  of  the 
National  Fire  Prevention  Committee  which  drew  up  the  proposed 
standard  code  on  theatre  construction  and  equipment,  this  method 
of  specifying  foyer  and  lobby  space  is  excellent,  but  the  space 
allotted  to  each  person  is  too  small.  Mr.  Blackall  has  recom- 
mended not  less  than  two  square  feet  of  space  per  person,  but 
the  proposed  standard  code  provides  for  a  compromise,  viz., 
an  aggregate  capacity  of  foyers,  lobbies,  hallways,  passages, 
etc.,  not  including  aisle  space,  on  each  tier,  to  accommodate  the 
entire  number  of  persons  on  such  tier,  at  the  ratio  of  150  square 
feet  of  floor  space  per  100  persons. 


716         FIRE   PREVENTION   AND   FIRE   PROTECTION 

The  ventilation  of  smoke  from  such  foyers,  lobbies,  etc.,  is 
important. 

Courts.  —  Previous  reference  has  been  made  to  emergency 
courts  which  are  usually  placed  at  the  sides  of  the  auditorium. 
In  the  absence  of  local  municipal  requirements,  the  following 
should  be  used  for  all  buildings  used  for  theatrical  or  operatic 
purposes,  or  for  motion  picture  shows: 

When  only  one  side  of  building  faces  on  a  street,  one  court 
must  be  located  on  the  opposite  side.  On  an  inside  plot,  where 
only  the  front  of  building  is  on  a  street,  courts  are  required  on 
both  sides.  Courts  to  be  not  less  than  8  ft.  wide  for  a  total 
capacity  of  750  persons  or  less,  — 10  ft.  for  between  750  and 
1,000,  —  to  be  increased  one  foot  for  each  additional  500  or 
fraction  thereof  in  excess  of  1,000.  Courts  to  extend  at  least  the 
full  depth  of  auditorium,  to  be  open  to  sky,  and  if  they  do  not 
open  directly  on  street,  fire-resisting  corridors  or  passages  to 
street  must  be  provided.  Passages  to  be  at  least  as  wide  as  the 
courts  served  by  them,  and  courts  or  corridors  to  be  flush  with 
street  at  entrances,  using  not  over  10  per  cent,  gradients  to  over- 
come differences  in  level,  or  not  over  12 J  per  cent,  gradients  in 
runs  not  over  10  ft.  long. 

Entrance  and  Exit  Doors. — Entrance  doors  should  never  be 
less  than  5  ft.  wide  in  the  clear,  nor  emergency  exit  doors  less  than 
4  ft.  wide.  The  New  York  law  requires  all  public  entrance  or 
exit  doors  to  be  not  less  than  5  ft.  in  width,  to  be  increased 
20  inches  for  each  100  persons  in  excess  of  500  to  be  accommo- 
dated. 

Hanging.  —  All  doors  should  open  out,  be  hung  so  as  not  to 
obstruct  the  width  of  passage,  and  be  provided  with  fastenings 
capable  of  instant  operation  from  the  inside.  Most  excellent 
devices  of  this  character  are  now  made,  —  as,  for  example,  the 
"Von  Duprin"  self-releasing  fire  exit  latch,  —  wherein  a  metal 
push  bar  across  the  entire  width  of  the  door  controls  top  and 
bottom  latch  bolts.  The  push  bars  are  placed  about  waist-high, 
and  the  least  pressure  on  same  releases  the  bolts  at  once.  No 
hardware  is  placed  on  the  outside  of  such  doors. 

Electric  door  openers,  controlled  by  a  push-button  on  stage  or 
in  manager's  office,  have  been  used,  notably  in  the  Abbey  Theatre 
in  New  York  City,  and  in  continental  theatres;  but  such  opera- 
tion is  liable  to  accident,  and  is  not  to  be  compared  with  the 
devices  mentioned  above. 


THEATRES  71 7 

Entrance  and  exit  doors  should  never  be  provided  with  locks; 
neither  should  false  doors  or  windows,  or  mirrors  resembling 
either,  ever  be  employed. 

Marking.  —  All  doors  opening  from  the  auditorium  should 
be  plainly  marked  with  signs,  preferably  illuminated  by  electric 
light,  with  letters  not  less  than  6  ins.  high.  If  exit  doors,  the 
sign  should  read  EXIT,  followed  by  the  number  of  the  doorway 
corresponding  with  the  number  marked  on  floor  plans  printed 
in  the  program.  If  leading  to  some  room,  such  as  coat  room,  or 
toilet,  etc.,  the  sign  should  be  marked  accordingly. 

Means  of  Egress. 

Stairs  should  be  planned  with  direct  course,  —  ample  width 
for  maximum  travel,  —  easy  rise,  —  wide  treads,  —  frequent 
landings,  —  rigid  wall  rails,  —  center  rails  for  wide  runs,  —  and 
ample  and  dependable  light.  In  other  words  they  should  be 
arranged  so  simply  and  safely  that  one  could  easily  traverse  them 
to  the  bottom,  even  in  darkness,  by  following  the  hand  rail. 

They  should  not  be  planned  with  "  winders,"  —  single  steps,  — 
long  unbroken  runs,  —  sharp  corners,  —  or  abrupt  changes  in 
direction. 

Most  building  laws  in  American  cities  prescribe  not  more  than 
7J  in.  rise,  not  less  than  10J  in.  tread,  with  a  maximum  number 
of  fifteen  risers  in  any  one  run.  For  this  length  of  run  the  step 
measures  given  above  are  too  steep  for  a  large  crowd  of  people. 
Fifteen-step  runs  should  preferably  have  risers  of  not  over  6J  ins., 
and  treads  of  not  less  than  12  ins.  The  7i-in.  by  lOj-in.  rise  and 
tread  should  not  be  used  for  runs  over  six  or  eight  steps.  Also, 
all  treads  not  carpeted  should  be  provided  with  some  form  of  non- 
slipping  tread,  such  as  the  Mason  Safety  Tread. 

For  further  details  as  to  stair  planning  and  construction,  see 
Chapter  XV.  For  special  requirements  as  to  stairs  in  theatres, 
see  local  building  codes,  or,  preferably,  the  standard  code  of  the 
National  Fire  Protection  Association. 

Double  or  Overlapping  Stairs  are  frequently  employed  in 
theatre  planning  to  economize  room.  This  device  was  used  by 
Mr.  Freeman  in  planning  one  set  of  balcony  and  gallery  stairs,  — 
see  Fig.  294,  —  but  the  arrangement  of  such  stairs,  in  their 
simplest  form,  is  more  plainly  shown  in  Fig.  313  which  illustrates 
their  application  to  schoolhouse  requirements.  Exactly  the  same 


718 


FIRE    PREVENTION   AND    FIRE    PROTECTION 


arrangement,  except  that  runs  are  used  on  all  four  sides  of  the 
well-room,  is  shown  in  Fig.  295.     Double  circular  stairs,  one  run 
over  the  other,  have  also  been  used  in  some  cases  —  notably 
in    the    "New    Theatre,"    New    York 
City. 

Inclines  or  Ramps  have  been  used 
to  some  extent  for  theatre  exits  instead 
of  stairs.  The  employment  of  this 
device  to  reach  both  parquet  and  bal- 
cony from  the  lobby  has  previously 
been  pointed  out.  See  page  703.  An 
incline  was  also  employed  by  Mr. 
Freeman  in  his  illustrative  plans,  to 
secure  exit  from  an  inside  stair  tower. 
See  Fig.  289.  In  the  Nixon  Theatre, 
Pittsburgh,  double  inclines  were  used 
from  the  foyer  to  balcony  at  a  grade 
of  1  :  12.  It  should  be  said,  however, 
that  their  use  is  almost  always  merely 
supplemental  to  regular  stairways, 
except  for  short  runs,  which  should 
always  be  inclines  where  possible. 

Escalators  have  also  been  used  in 
some  theatres  as  an  additional  means 
of  communication  between  levels  — 
one  run  from  lobby  to  balcony,  and 
a  separate  run  from  balcony  to  gallery. 
Of  course,  they  only  supplement  ade- 
quate stairways,  but  even  so,  their  use 
should  be  condemned.  No  device 
which  is  subject  to  breakdown  should 
be  permitted  for  public  use. 
Lighting.  —  The  lighting  of  all  stairs,  inclines,  escalators,  etc., 
should  be  so  arranged  as  to  be  at  least  partially  independent  of 
the  main  source  of  supply.  In  some  instances  one-half  the 
corridor  and  stair  lights  and  other  important  emergency  lights  are 
placed  on  a  separate  circuit  which  may  be  thrown  in  immediately, 
when  desired.  Mr.  Blackall  has  also  used  small  storage  batteries, 
in  series,  connected  with  the  exit  lights,  so  that,  in  case  of  acci- 
dent to  the  main  service,  the  battery  storage  would  maintain 
the  exit  lights  for  at  least  twenty  minutes. 


FIG.  295.  —  Double  or  Over- 
lapping Stairs. 


THEATRES 


719 


It  should  be  needless  to  say  that  illuminating  gas  should  never 
be  used  in  theatres. 

Outside  Fire  Escapes  have  been  considered  in  detail  in  Chap- 
ter XV,  but  for  theatres  and  other  buildings  of  public  assembly, 
especial  care  is  necessary  in  both  design  and  construction.  The 
large  number  of  people  who  may  have  to  rely  on  such  means  of 
escape  in  time  of  emergency  makes  the  light,  flimsy,  and  poorly- 
designed  fire  escape  of  ordinary  pattern  wholly  unsuitable.  But 
the  plan  or  arrangement  of  fire  escapes  is  fully  as  vital  as  their 
construction. 


East 


West 


Fia.  296.  —  Fire  Escapes  on  Iroquois  Theatre. 


The  fire  escapes  which  were  provided  in  the  rear  of  the  Iroquois 
Theatre,  as  shown  in  Fig.  296,  have  been  termed,  by  Mr.  Freeman, 
fire  traps,  instead  of  fire  escapes. 

The  fire  and  smoke  issuing  from  the  door  marked  *F' 
ascended  and  enveloped  the  fire  escape  leading  down  from  the 
upper  gallery,  so  that  many  who  crowded  out  through  the  door- 
way and  stood  on  the  upper  platform  at  'A'  could  not  descend, 
and  several  in"  their  terror  jumped  about  40  feet  to  their  death 
on  the  hard  ground  below. 

As  regards  the  construction  of  fire  escapes,  the  following 
regulations  should  be  rigidly  followed : 

All  exit  balconies  and  stairs  shall  be  constructed  of  steel 
throughout  or  of  other  forms  of  fireproof  construction  approved 
by  the  Superintendent  of  Buildings.  Risers,  treads,  platforms 


720         FIRE   PREVENTION   AND   FIRE   PROTECTION 

and  balconies  must  be  solid,  without  perforations  or  slats,  and 
the  construction  must  be  of  strength  to  safely  sustain  a  live  load 
of  100  pounds  per  square  foot.  Sheet  metal  or  other  suitable 
solid  material  shall  be  provided  to  a  height  of  not  less  than  4  feet 
on  the  outer  side  of  all  these  open  air  stairs,  balconies  and  plat- 
forms. All  open  air  stairs,  balconies  and  platforms  shall  be 
covered  with  a  metal  hood  or  awning  to  be  constructed  in  such 
a  manner  as  shall  be  approved  by  the  Superintendent  of  Buildings. 
There  shall  be  no  openings  in  any  theatre  wall  between  the  out- 
side balconies  or  stairways  and  their  covers,  except  the  required 
exits  from  the  tier  served  by  said  stairs  and  balconies.  No  person 
of  the  audience  must  be  obliged  to  pass  alongside  of  more  than 
one  exit  doorway  after  reaching  an  outside  balcony  to  get  to  the 
ground.  All  exit  stairs  and  balconies  shall  be  kept  free  of  ob- 
structions of  every  kind  including  snow  and  ice.§ 

The  hoods  or  awnings  specified  above  are  of  two-fold  value; 
they  serve  to  prevent  flames  from  exit  doors  extending  to  fire 
escapes  above,  and  also  to  protect,  somewhat,  the  stairs  and 
landings  from  snow  and  ice. 

The  Stage  and  Its  Appurtenances.  —  The  principal  features 
in  connection  with  the  stage  which  demand  special  consideration 
from  a  fire  protection  viewpoint  include  the  cutting  off  of  stage 
from  auditorium  by  means  of  proscenium  wall  and  fire  curtain, 
vents  over  stage,  the  safety  of  the  stage  personnel,  the  construc- 
tion of  fly  galleries,  gridiron  and  roof,  and  preventive  measures 
in  connection  with  the  stage  furnishings. 

The  Proscenium  Wall  should  preferably  comply  with  the 
the  following  requirements: 

A  fire  wall  built  of  brick  or  concrete  not  less  than  twelve 
inches  thick  in  any  portion  shall  separate  the  auditorium  from  the 
stage  and  shall  extend  at  least  four  feet  above  the  stage  roof,  or 
the  auditorium  roof  if  the  latter  be  the  higher.  Any  windows  in 
the  structure  above  the  auditorium  which  face  over  roof  of  stage 
section  when  within  100  feet  of  the  stage  roof  must  be  protected 
with  wired  glass  windows  in  metal  frames  with  automatic  closing 
attachments.  All  windows  within  30  feet  shall  also  be  protected 
by  shutters.  Above  the  proscenium  opening  there  shall  be  a 
girder  or  other  support  of  sufficient  strength  to  carry  safely  the 
load  above,  and  it  shall  be  properly  fireproof  ed. 

Openings  between  the  stage  and  auditorium  other  than  the 
proscenium  opening  shall  not  exceed  four  in  nuniber,  two  at  the 
approximate  stage  level  and  two  in  the  musicians'  pit;  the  size 
of  any  such  openings  shall  not  exceed  21  square  feet.  The  open- 
ings at  stage  level  shall  have  an  automatic  fire  door  on  one  side 
of  the  wall  and  a  self-closing  fireproof  door  at  the  other  side  of  the 
wall,  and  openings,  if  any,  below  the  stage  shall  have  a  self-closing 


THEATRES  721 

fire  door,  and  all  of  said  doors  shall  be  hung  so  as  to  be  opened 
from  either  side  of  the  wall  at  all  times.  § 

If  a  steel  girder  or  truss  is  used  over  the  proscenium  opening, 
the  same  should  be  thoroughly  protected.  • 

Fire  Curtains.  —  Since  the  Iroquois  Theatre  fire,  no  detail 
of  theatre  construction  has  been  so  thoroughly  discussed  in  public 
print  as  the  matter  of  fire  curtains.  The  importance  of  the  fire 
curtain,  forming  as  it  does,  the  vulnerable  portion  of  the  pro- 
scenium wall,  and  acting  as  a  cut-off  to  prevent  flame,  smoke  and 
gases  from  entering  the  auditorium  from  the  stage,  is  em- 
phasized by  all  authorities,  and  demonstrated  by  tests,  both 
experimental  and  actual. 

Austrian  Experiments.  —  As  a  direct  result  of  the  fatal 
Ring  Theatre  fire  in  Vienna  in  1881,  a  committee  of  the  Austrian 
Society  of  Engineers  made,  in  1885,  a  series  of  experimental  tests 
with  a  model  of  the  Ring  Theatre  built  to  one-tenth  lineal  scale. 

Two  sets  of  experiments  were  made  to  investigate  what 
Mr.  Sachs  calls  the  three  periods  of  a  theatre  fire,  —  the  first 
period  comprising  the  time  during  which  the  stage  is  afire,  but 
before  flame  is  communicated  to  the  auditorium,  —  the  second 
period  being  when  the  auditorium  is  well  alight,  —  and  the  third 
period  covering  the  final  destruction  of  the  entire  building. 

The  first  set  of  experiments  was  made  with  the  vents  over 
stage  tightly  closed.  Actual  stage  conditions  were  simulated  by 
hanging  sheets  of  paper  to  represent  scenery,  the  amount  of  com- 
bustible material  being  proportionately  less  than  frequently 
occurs  in  actual  practice.  The  danger  to  an  audience  during 
the  first  period  was  clearly  shown,  especially  in  the  rapid  travel 
of  deadly  fumes  from  stage  to  auditorium.  The  gases  on  the 
stage  expanded  so  rapidly  that,  within  17  seconds,  the  curtain 
was  blown  into  the  auditorium;  and  even  before  the  auditorium 
was  filled  with  smoke,  the  gas  lights  were  extinguished  by  pres- 
sure of  air  from  the  stage.  The  highest  pressure  occurred  within 
20  seconds  of  the  stage  being  well  alight,  and  was  of  sufficient 
intensity  to  enter  the  gas-piping,  drive  back  the  gas,  and  even  to 
extinguish  lights  outside  of  the  auditorium.  These  experiments 
seemed  to  prove,  conclusively,  why  the  lights  in  the  Ring  Theatre 
were  extinguished  so  soon  after  the  outbreak  of  fire.  They  also 
demonstrated  the  unsuitability  of  gas  as  a  means  of  illumination. 

In  the  second  series  of  tests,  the  two  stage  vents,  equaling 
about  one-tenth  of  the  stage  area,  were  closed  by  sheets  of  paper, 
in  an  effort  to  approximate  conditions  of  automatic  opening. 
The  first  vent  opened  in  12  seconds,  and  the  second  in  20  seconds 
after  the  outbreak.  No  dangerous  gases  entered  the  auditorium, 
and  no  gas  lights  were  extinguished.  On  the  contrary,  the 
draught  from  the  auditorium  to  the  stage  was  so  great  as  to  bulge 


722         FIRE   PREVENTION   AND    FIRE    PROTECTION 

the  iron  curtain  toward  the  stage  to  such  an  extent  as  to  cause 
collapse. 

A  later  series  of  similar  tests  was  made  in  Vienna,  in  1905, 
by  the  Austrian  Government.  A  model  of  reinforced  concrete 
was  used,  approximating  |rd  the  linear  dimensions  (or  ^7th  of 
the  cubical  contents)  of  an  ordinary  theatre.  The  deductions 
were  almost  precisely  as  in  the  earlier  series,  — viz.,  the  efficiency 
of  open  stage  vents,  and  the  danger  to  audience  when  such  vents 
were  closed.  In  the  latter  case,  the  air  pressure  was  sufficient  to. 
prevent  the  quick  operation  of  curtain,  and  even  when  down,  gas 
and  flames  were  soon  driven  around  its  edges  into  auditorium. 

Types  of  Fire  Curtains  comprise  those  of  wire  gauze,  for- 
merly used  in  some  continental  theatres,  but  now  generally 
abandoned,  —  woven  asbestos  curtains,  —  solid  metal  curtains, 
—  and  combination  steel  and  asbestos  curtains. 

The  Form  may  be  either  a  " sliding"  curtain,  where  the  curtain 
is  made  to  slide  in  front  of  the  opening,  either  in  one  piece,  or  in 
pieces  from  either  side,  —  a  " shutter"  curtain,  wherein  three 
leaves  similar  to  shutters  are  hung,  two  at  the  sides,  and  one  at 
the  top  of  proscenium  opening,  the  three  locking  together,  —  or, 
as  is  now  almost  universal,  a  "drop"  curtain,  usually  lowered 
from  above. 

The  Operation  may  be  manual,  hydraulic,  electric,  or,  as  is  gen- 
erally required,  a  combination  of  the  manual  with  either  of  the 
others. 

Functions  of  Fire  Curtains.  —  It  should  be  evident  from 
the  preceding  portion  of  this  chapter  that  a  proscenium  arch  fire 
curtain  is  not  intended,  in  the  absence  of  other  means  of  fire 
protection,  to  confine  indefinitely  a  fire  originating  on  the  stage 
to  that  location.  It  is  more  than  probable  that  no  practicable 
curtain  could  be  devised  which  would  accomplish  this. 

The  primary  object  of  a  fire  curtain  is  to  confine  fire  originating 
on  the  stage  a  sufficiently  long  time  to  permit  the  audience, 
under  the  worst  conditions,  to  evacuate  the  building  completely; 
and,  as  has  been  seen  in  connection  with  the  Iroquois  Theatre, 
this  may  be  as  long  as  eight  or  nine  minutes,  or  even  more,  after 
the  outbreak. 

The  protection  of  property,  or  the  absolute  separation  of  fire 
on  stage  from  auditorium,  should  be  but  a  secondary  considera- 
tion; but  even  this  function  may  be  realized  if  the  curtain  is 
designed  with  that  end  in  view,  and  if  the  stage  is  provided  with 
adequate  means  of  fire  protection  to  reenforce  the  curtain.  In 


THEATRES  723 

continental  cities,  the  ordinary  drop  curtain  is  frequently  re- 
quired to  be  of  woven  asbestos,  in  addition  to  a  separate  fire 
curtain.  This  provision  is  wise  in  that  such  a  curtain  would  go 
far  to  protect  the  fire  curtain  from  the  severity  of  a  stage  fire. 
The  so-called  " harlequin"  and  even  the  first  set  of  wings  are  also 
sometimes  made  of  asbestos. 

Woven  Asbestos  Curtains.  —  Prior  to  the  Iroquois  Theatre 
fire,  the  woven  asbestos  drop  curtain  was  the  usual  type  in  most 
American  theatres;  indeed,  it  is  still,  in  those  cities  where 
something  better  is  not  required. 

Such  curtains  are  generally  made  of  what  is  known  as  "  metallic 
asbestos  cloth,"  where  each  strand  of  asbestos  yarn  is,  in  the 
process  of  manufacture,  wound  with  a  strand  of  fine  brass  wire, 
and  this  combination  of  asbestos  thread  and  wire  is  then  twisted 
and  woven  into  asbestos  cloth.  This  cloth  is  usually  woven  in 
widths  of  36  ins.,  and  the  curtain  is  made  of  these  widths  running 
longitudinally,  or  up  and  down,  in  the  curtain,  being  lapped  about 
two  inches  and  sewed  together  with  asbestos  thread  or  sewing 
twine.  These  curtains  are  furnished  with  roll  pockets  at  the 
base  and  at  top,  through  which  are  run  suitable-sized  galvanized- 
iron  pipes,  the  lower  one  as  a  weight  and  stiffener,  and  the  upper 
one  to  receive  the  attachment  of  the  raising  devices.  The  audi- 
torium face  is  then  generally  painted  by  the  scenic  artists. .  The 
largest  curtain  of  this  type  of  which  the  writer  has  knowledge  is 
that  in  the  New  York  Hippodrome,  which  measures  95  ft.  8  ins. 
in  width  by  37  ft.  7  ins.  high. 

The  objections  to  such  curtains  are  three-fold.  They  are  not 
sufficiently  fire-resisting  to  guarantee  an  endurance  long  enough 
to  allow  the  audience  to  escape,  —  they  are  not  proof  against 
tearing  or  puncture  from  falling  objects,  —  and  they  are  not 
sufficiently  reliable,  even  when  reinforced  by  stage  sprinklers, 
etc.,  to  act  as  an  efficient  cut-off  in  saving  the  auditorium  from 
a  prolonged  fire. 

Notwithstanding  public  opinion  to  the  contrary,  asbestos  fibre 
or  asbestos  cloth  is  far  from  fire-resisting  as  the  term  is  now 
properly  used.  Asbestos  fibre  loses  its  water  of  combination  at 
a  temperature  of  between  700  and  800  degrees  Fahrenheit,  so  that 
a  heat  of  1,500  or  2,000  degrees  soon  dissipates  the  chemically 
combined  water,  and  causes  the  fibres  to  lose  strength  in  a  re- 
markably short  time.  The  fusing  of  the  glass  in  the  skylights 
over  the  Iroquois  stage  indicated  a  temperature  of  1,650°  F. 


724        FIRE    PREVENTION    AND    FIRE    PROTECTION 

Experimental  Tests.  —  The  most  exhaustive  tests  of  asbestos 
cloth  or  asbestos  canvas  which  have  ever  been  made  by  a  dis- 
interested observer  are  undoubtedly  those  made  by  Mr.  John  R. 
Freeman  immediately  after  the  Iroquois  disaster.  From  numer- 
ous and  careful  experiments,  Mr.  Freeman  concludes  as  follows:* 

In  brief,  we  found  that  every  one  of  these  specimens  of  asbestos 
canvas,  English,  French  and  American  alike,  when  heated  for  from 
two  to  five  minutes  to  a  little  below  redness  in  a  common  gas  flame, 
or  barely  to  redness  in  the  Bunsen  flame,  lost  from  sixty  per  cent,  to 
ninety  per  cent,  of  its  strength,  and  that  the  fibre  became  very 
brittle. 

We  were  surprised  to  find  that  the  samples  with  the  wire 
insertion,  when  tested  hot,  were  no  stronger  than  the  samples 
without  wire.  On  cooling,  they  regained  a  little  of  the  strength 
due  to  the  wire. 

Actual  Tests  of  asbestos  curtains  in  theatre  fires  may  be  cited 
as  follows : 

The  Girard  Avenue  Theatre,  in  Philadelphia,  was  destroyed 
October  28,  1904,  by  a  fire  which  broke  out  on  the  stage  at  about 
3  A.M.  On  the  arrival  of  the  firemen,  about  three  minutes  after 
the  alarm  was  turned  in,  no  fire  or  smoke  was  to  be  seen  in  the 
auditorium;  and,  possibly  aided  by  a  cool  indraft  from  the  audi- 
torium to  the  open  vents  over  stage,  the  asbestos  curtain  acted 
as  a  •  shut-off  for  some  fifteen  minutes.  After  this,  however, 
whether  due  to  falling  debris  or  to  passing  the  edges  of  curtain, 
flames  soon  entered  and  destroyed  the  auditorium. 

The  Iroquois  Theatre  was  also  provided  with  an  asbestos 
curtain  which  failed,  at  the  critical  moment,  to  work  properly. 
As  to  its  condition,  Mr.  Freeman  made  a  minute  examination 
shortly  after  the  fire,  with  the  following  result: 

The  asbestos  canvas  of  the  Iroquois  curtain,  when  exposed 
to  actual  fire,  lost  its  strength  and  fibrous  quality  almost  com- 
pletely, and  became  so  brittle  that  it  would  crumble  under  a  very 
slight  pressure,  and  became  utterly  incapable  of  withstanding 
the  pressure  of  a  strong  draft  of  air,  and  too  weak  to  hang  up 
under  its  own  weigh t.f 

Metallic  Fire  Curtains.  —  In  England  and  in  continental 
cities,  preference  has  generally  been  given  to  metallic  curtains 
made  of  wire  gauze  or  netting,  and,  more  recently,  of  flat  or 
finely-corrugated  iron. 

*  See  "On  the  Safeguarding  of  Life  in  Theatres,"  by  John  R.  Freeman,  page 
45.  t  Ibid. 


THEATRES 


725 


Wire  gauze  curtains,  while  preventing  the  passage  of  flames 
from  stage  to  auditorium,  —  like  the  Davy  miner's  lamp,  —  do 
not  prevent  the  passage  of  smoke  or  gas,  and,  what  is  also  im- 
portant, do  not  prevent  the  audience  from  obtaining  a  full  view 
of  the  conditions  on  the  stage.  A  curtain  of  this  type  was  hung 
in  the  Ring  Theatre,  but  it  is  problematical  how  much  it  would 
have  protected  the  audience,  inasmuch  as  it  was  not  lowered. 
The  use  of  such  wire  curtains  has  been  abandoned. 


FIG.  297.  —  Fire  Curtain,  Prinz  Regenten  Theatre,  Munich,  Bavaria. 

Flat  iron  curtains  have  been  used  to  some  extent,  but  they 
have  not  proved  sufficiently  rigid  in  practice  to  resist  the  in- 
creased air  pressure  which  so  quickly  follows  fire  on  the  stage. 
They  have  frequently  buckled  out  in  the  center. 

Corrugated-iron  curtains  are  largely  used  in  continental  cities. 
They  are  strong,  and,  if  properly  hung  and  guided,  are  also  smoke 
proof.  They  should  amply  protect  an  audience  during  the  time 
required  to  clear  a  theatre,  but,  unless  reinforced  by  automatic 
sprinklers,  " Regan"  nozzles,  or  some  such  device,  they  cannot 
be  termed  fire-resisting.  Fig.  297  illustrates  the  stage  side  of 
the  corrugated-iron  curtain  in  the  Prinz  Regenten  Theatre, 
Munich. 


726 


FIRE   PREVENTION    AND    FIRE    PROTECTION 


ELEVATION   FROM    STAGE  SIDE 
-44'-6— 


PLAN 

FIG.  298.  —  "Kinnear"  Fire  Curtain,  Hartman  Theatre,  Columbus,  Ohio. 

An  improvement  on  the  ordinary  corrugated-iron  curtain  has 
been  devised  by  the  Kinnear  Manufacturing  Co.,  whereby  the 
perfect  closure  of  the  proscenium  opening,  the  expansion  of  all 
parts,  and  the  secure  anchoring  and  hanging  of  curtain  have  been 
secured.  In  brief,  the  construction  is  as  follows: 

The  curtain  is  composed  of  sectional  units  formed  in  steel, 
the  edges  of  which  interlock.  These  are  assembled  in  a  vertical 
position  and  attached  at  the  top  to  a  fireproofed  lattice  girder. 
The  curtain  is  expandable  in  every  direction;  horizontal  expan- 
sion is  taken  care  of  partly  by  the  joints  at  the  edges  of  units, 


THEATRES 


727 


and  partly  by  providing  expansion  spaces  in  the  side  grooves  or 
guides;  vertical  expansion  is  cared  for  by  slotted  holes  in  the 
bottom  member  which  rests  on  the  stage.  All  connections  are 
made  by  means  of  bolts  in  slotted  holes.  The  curtain  is  hung  by 
means  of  steel  cables  running  from  the  .latticed  girder  at  top  of 
curtain  to  the  counterweights  at  side  of  arch,  and  further  support 
and  stiffness  are  secured  by  means  of  six  overhead  rods,  assembled 
in  pairs,  the  upper  ends  of  which  are  supported  in  air-cushion 
cylinders.  Stops  on  these  rods  cause  the  cylinders  to  act  as  air 
cushions.  All  metal  is  used  in  tension  only,  thereby  avoiding  the 
objection  of  employing  compression  members  exposed  to  heat. 

Fig.  298  illustrates  a  curtain  of  this  make  installed  in  the  Hart- 
man  Theatre,  Columbus,  Ohio,  the  proscenium  opening  measur- 
ing 38  ft.  wide  by  31  ft.  6  ins.  high.  A  similar  curtain  has  been 
used  in  a  theatre  in  Dayton,  Ohio. 


FIG.  299.  —  Detail  of  "Kinnear"  Fire  Curtain. 

Fig.  299  illustrates  a  cross-section  and  part  elevation  of  a 
similar  " Kinnear"  fire  curtain  devised  for  use  in  a  London 
theatre  of  which  Mr.  Edwin  O.  Sachs  was  the  architect.  It  will 
be  noted  that  the  sides  of  the  curtain,  where  running  in  the  guide 


728 


FIRE    PREVENTION    AND    FIRE    PROTECTION 


grooves,  are  fitted  with  a  plate  and  pair  of  angles, 


L 


r 


",  to 


which  are  fitted  strips  of  wood  or  wood  fibre,  to  prevent  noise  in 
operation.  Also,  continuous  plates  extend  from  the  grooves  to 
the  proscenium  wall,  so  that,  except  at  the  top,  a  perfect  closure 
of  the  stage  opening  is  effected.  An  emergency  closing  device 
may  be  attached,  in  addition  to  the  usual  power-operating 
machinery. 

Combination  Steel  and  Asbestos  Curtains  may  consist  of 
merely  a  framework  of  steel  shapes  to  which  woven  asbestos  is 
attached,  or  of  a  solid  steel  curtain  which  is  protected  by  means 
of  asbestos  in  some  suitable  form. 


D 


E 


Jc.w. 


FIG.  300.  —  Combination  Steel  and  Woven  Asbestos  Fire  Curtain. 

An  example  of  the  former  type,  frequently  found  in  London 
theatres,  is  illustrated  in  Figs.  300  and  301.  The  framework 
consists  of  angles,  to  which  the  asbestos  sheets  are  bolted  with 


Int.  L  Frame 
^Guide 
FIG.  301.  —  Detail  of  Steel  and  Woven  Asbestos  Fire  Curtain. 


THEATRES  729 

continuous  washers  of  hoop-  or  band-iron.  A  double  curtain  is 
sometimes  made  by  substituting  channels  for  angles,  and  using 
an  inside  and  outside  covering  of  woven  as-  ^Band  Iron 
bestos,  as  in  Fig.  302. 

While    more   rigid    against    buckling    or   .  x  Asbestos 

deflection  from  air  currents,  these  types  are 
still  open  to  nearly  all  the  objections  obtain- 
ing in  the  unstiffened  woven-asbestos  cur-  FIG.  [302. —  Double 
tain.  Hence  the  suggestion,  often  made  Woven  Asbestos  Fire 
after  the  Iroquois  Theatre  fire,  to  utilize 
the  strength  and  rigidity  of  a  steel  curtain,  but  to  insulate  such 
steel  work,  on  the  stage  side,  by  means  of  asbestos  or  other  suit- 
able material.  Mr.  Freeman  made  various  experiments  with 
asbestos,  asbestos  felt,  and  asbestic  cement,  in  combination  with 
wire  netting  and  thin  steel  plates.  These  tests  "were  carried  far 
enough  to  prove  an  endurance  more  than  ample  for  their  purpose 
as  a  shield  while  the  audience  is  escaping,  and  it  was  plain  to  all 
who  witnessed  these  tests  that  the  sheet-steel  curtain,  protected 
with  some  asbestic  material  on  the  fire  side,  possessed  far  greater 
strength  and  endurance  against  fire  than  the  simple  asbestos. 
The  thin  sheet  of  steel,  moreover,  cut  off  the  view  of  the  fire  that 
was  apparent  through  the  texture  of  the  asbestos  canvas." 

This  method  was  also  given  careful  consideration  by  the  special 
committee  of  the  National  Fire  Protection  Association  reporting 
on  "Theatre  Construction  and  Equipment,"  —  May,  1911,  — 
with  the  result  that  the  following  specifications  were  recom- 
mended for  general  adoption: 

Proscenium  Curtain. 

The  proscenium  opening  shall  be  provided  with  a  rigid 
fireproof  curtain,  built  in  conformity  with  the  following  specifica- 
tions, or  their  equivalent  in  efficiency  when  approved  by  the 
Superintendent  of  Buildings. 

The  curtain  shall  have  a  rigid,  rivet-jointed,  steel  frame- 
work. The  front  or  audience  side  of  the  frame  shall  be  covered 
with  sheet  steel  of  a  thickness  not  less  than  No.  16  U.  S.  gauge. 
The  back  shall  be  covered  with  cellular  asbestos  boards  at  least 
one  inch  thick,  or  other  material  equally  fire-resisting.  Both 
coverings  shall  be  securely  attached  to  the  framework  and  the 
joints  properly  sealed.  The  curtain  shall  be  designed  to  resist  a 
wind  pressure  of  ten  pounds  per  square  foot  of  surface  without 
flexure  sufficient  to  interfere  with  its  closing. 

The  thickness  of  the  curtain  shall  be  not  less  than  3  inches 
where  the  width  of  the  proscenium  wall  opening  is  30  feet  or  less, 


730         FIRE    PREVENTION    AND    FIRE    PROTECTION 

and  curtains  for  larger  openings  shall  increase  in  thickness  in 
proportion  to  the  increase  in  width  of  opening  they  cover. 

An  asbestos  roll  of  a  diameter  not  less  than  one  half  the 
thickness  of  the  curtain  shall  be  securely  attached  to  the  bottom 
of  the  curtain  to  form  a  smoke  seal  between  the  curtain  and  the 
stage. 

The  curtain  shall  overlap  the  proscenium  wall  12  inches 
at  the  sides  and  not  less  than  2  feet  at  the  top. 

The  guide  members  at  the  sides  shall  be  rolled-steel  shapes, 
none  of  which  shall  be  less  than  f  inch  thick,  and  shall  be  of  such 
character  as  to  form  a  continuous  smoke  stop  from  top  to  bottom, 
with  a  clearance  of  not  over  |  inch. 

They  shall  be  installed  in  such  manner  that  in  case  of  fire 
on  the  stage  the  pressure  of  heated  gases  against  the  curtain  will 
act  to  close  the  guide  joints  tightly.  Provision  shall  be  made  to 
prevent  the  curtain  from  getting  out  of  the  guiding  channel.  The 
proscenium  wall  shall  have  an  offset  at  each  side  of  the  opening, 
so  located  and  of  such  thickness  and  height  as  to  be  suitable  for 
the  attachment  of  the  curtain  guides. 

The  wall  over  the  proscenium  opening  shall  be  smooth  and 
plumb  to  approximately  the  top  of  the  curtain  when  it  is  down, 
and  shall  then  offset  at  least  4  inches  for  the  rest  of  its  height, 
thus  leaving  a  bench  along  the  line  of  the  top  of  the  curtain  be- 
tween which  a  smoke  seal  shall  be  formed  by  use  of  rolled-steel 
shapes.  The  clearance  at  the  joint  of  this  seal  shall  not  exceed 
J  inch. 

No  part  of  a  curtain  or  any  of  the  curtain  guides  shall  be 
supported  by,  or  fastened  to,  any  combustible  material. 

The  hoisting  apparatus  for  the  curtain  shall  be  designed 
with  a  factor  of  safety  of  8. 

The  points  for  curtain  suspension  shall  always  be  an  even 
number,  but  never  less  than  four.  Two  of  the  suspension  points 
shall  be  located  at  the  extreme  ends  of  the  curtain,  and  the  others 
may  be  placed  at  such  points  as  best  suit  the  design,  but  in  no 
case  shall  the  distance  between  any  two  points  of  support  exceed 
10  feet. 

Half  of  the  cables  attached  to  these  points  shall  lead  to  one 
set  of  counterweights  and  half  to  another.  The  curtain  shall  be 
operated  by  hydraulic  or  other  mechanism  approved  by  the 
Superintendent  of  Buildings.  If  hydraulic  mechanism  is  used, 
the  water  shall  be  taken  from  either  the  house-tank  or  sprinkler- 
tank  supply.  If  from  the  latter,  the  supply  pipe  for  curtain 
mechanism  shall  be  so  located  in  the  tank  that  it  cannot  reduce 
the  quantity  of  water  below  the  amount  necessary  to  fulfill  the 
sprinkler  requirements. 

The  device  for  controlling  the  curtain  shall  be  simple  in 
design,  and  capable  of  convenient  operation  from  both  sides  of 
the  stage  and  from  the  tie  galleries. 

The  drop  speed  of  the  curtain  shall  be  uniform  and  not  less 
than  1  foot  per  second,  but  when  the  curtain  is  about  2i  feet  from 
the  stage  it  shall  automatically  slow  down  so  as  to  settle  on  the 
stage  without  shock. 


THEATRES  731 

Besides  the  regular  operating  mechanism,  there  shall  be 
an  emergency  device  which  will  cut  off  the  power  and  allow  the 
curtain  to  drop  by  gravity.  This  device  shall  be  so  arranged  that 
it  can  be  easily  operated  by  hand  from  each  side  of  the  stage, 
under  the  stage,  and  in  the  tie  galleries/  The  device  shall  also 
be  so  designed  that  its  operation  will  be  controlled  by  fusible 
links  located  at  each  of  the  above  named  points. 

The  audience  side  of  the  curtain  may  be  decorated  with  a 
paint  in  which  no  oil  is  used.  No  combustible  material  shall  be 
applied  or  attached  to  the  curtain. 

Drawings  for  every  such  curtain  shall  be  submitted  to  the 
Superintendent  of  Buildings  and  be  approved  by  him  before  it  is 
erected. 

The  curtain  shall  be  operated  at  the  beginning  of  each 
performance. 

Stage  Vents. —  "The  foremost  problem  of  safeguarding  life 
in  theatres  is  to  give  prompt  and  certain  vent  to  smoke  and  suffocating 
gas  elsewhere  than  through  the  proscenium  arch."* 

The  importance  of  adequate  vents  over  the  stage  has  been 
sufficiently  attested  in  the  Austrian  experiments  previously  de- 
scribed, and  in  the  Iroquois  and  other  theatre  fires.  Nearly  all 
building  laws  recognize  the  necessity  of  such  vents,  but  little 
uniformity  of  practice  has  hitherto  prevailed,  and  theatre  owners 
or  managers  have  not  seemed  to  appreciate  the  vital  importance 
of  this  feature.  Hence  the  flagrant  examples  of  vents  obstructed 
or  rendered  inoperative  by  every  conceivable  means. 

The  New  York  Building  Code  requires  the  following : 

There  shall  be  provided,  over  the  stage,  metal  skylights  of 
an  area  or  combined  area  of  at  least  one-eighth  the  area  of  said 
stage,  fitted  up  with  sliding  sash  and  glazed  with  double  thick 
sheet  glass  not  exceeding  one-twelfth  of  an  inch  thick,  and  each 
pane  thereof  measuring  not  less  than  300  square  inches,  and  the 
whole  of  wilich  skylight  shall  be  so  constructed  as  to'  open  in- 
stantly on  the  cutting  or  burning  of  a  hempen  cord,  which  shall 
be  arranged  to  hold  said  skylights  closed,  or  some  other  equally 
simple  approved  device  for  opening  them  may  be  provided. 
Immediately  underneath  the  glass  of  said  skylights  there  shall 
be  wire  netting,  but  wire  glass  shall  not  be  used  in  lieu  of  this 
requirement. 

The  mention  of  a  hempen  cord  instead  of  fusible  links  attests 
the  antiquity  of  the  above.  The  purpose  of  the  thin  glass  speci- 
fied is  evidently  to  provide  some  weather  covering  which  may 
fail  under  fire  in  case  the  automatic  device  fails,  while  the  wire 
netting  under  the  glass,  of  which  more  anon,  is  intended  to  prevent 

*  "On  the  Safeguarding  of  Life  in  Theatres,"  by  John  R,  Freeman. 


732        FIRE   PREVENTION   AND   FIRE   PROTECTION 


any  pieces  of  glass  from  falling  on  the  stage.     Vague  and  un- 
satisfactory  as   are  the   above  requirements,   they  have  been 
copied  frequently  in  other  municipal  regulations,  until  it  is  high 
time  that  such  ordinances  be  thoroughly  revised. 
The  Boston  law  is  much  simpler  and  better: 

There  shall  be  one  or  more  ventilators,  near  the  center  and 
above  the  highest  part  of  the  stage  of  every  theatre,  of  a  com- 
bined area  of  opening  satisfactory  to  the  commissioner,  but  not 
less  than  one-tenth  of  the  area  of  the  undivided  floor  space  behind 
the  "curtain  at  the  stage  level.  The  openings  in  every  such 
ventilator  shall  be  closed  by  valves  or  louvres  so  counterbalanced  • 
as  to  open  automatically,  which  shall  be  kept  closed,  when  not 
in  use,  by  a  fusible  link  and  cord  reaching  to  the  prompter's  desk, 
and  be  readily  operated  therefrom.  Such  cord  shall  be  of  com- 
bustible material,  and  so  arranged  that  if  it  is  severed  the  ven- 
tilator will  open  automatically.  .  .  .  Skylight  coverings  shall 
have  metal  frames  set  with  double-thick  glass,  ...  or  shall  be 
protected  with  wire  glass.  If  wire  glass  is  not  used,  a  suitable 
wire  netting  shall  be  placed  immediately  beneath  the  glass,  but 
above  the  ventilator  opening. 

Types.  —  Figs.  303,  304  and  305  illustrate  various  arrange- 
ments of  stage    monitor-vents  which  have  been  used  by  Mr. 

Blackall    under    the    require- 
ments of  the  Boston  law. 

Fig.  303  shows  an  arrange- 
ment of  counterweighted 
louvres  held  shut  by  cord  and 
fusible  link.  This  type  was 
used  in  the  Colonial  Theatre, 
but  has  now  been  superseded 
by  a  better  type. 

Fig.  304  illustrates  a  double 


fLink 

I 

FIG.  303.  —  Stage  Vent  with  Counter- 
weighted  Louvres.  sliding  skylight,  in  which  the 
release  of  the  fusible  link  permits  the  two  sections  of  skylight  to 
slide  on  track  and  rollers  by  gravity.     This  method  was  used  in 

Sliding 
Skylight 


Stop 


FIG.  304.  —  Stage  Vent  with  Double  Sliding  Skylights. 


the  Park  Theatre  at  Waltham,  Mass.,  but  is  not  to  be  recom- 
mended as  the  junction  of  the  skylight  sections  is  hard  to  keep 


THEATRES 


733 


tight,  and  the  skylight  sections  are  necessarily  so  heavy  that  their 
release  by  accident  is  liable  to  cause  considerable  damage  to  both 
the  skylight  and  the  roof.  One  instance  is  known  where  the 
accidental  release  permitted  the  sections  t.o  roll  with  such  momen- 
tum as  to  carry  one  section  to  the  street. 


Counterbalanced 
Skylights 


FIG.  305.  —  Stage  Vent  with  Counterbalanced  Skylights. 


Fig.  305  illustrates  a  counterbalanced  skylight,  as  used  in  the 
Gaiety,  Casino,  National,  and  Plymouth  Theatres  in  Boston. 
The  arrangement  is  practically  ideal  from  the  standpoint  of  fire, 
but  is  very  difficult  to  keep  tight  against  weather. 


Rope  to  Prompters 

Stand  SCALE  OF  FEET 

FIG.  306.  —  Stage  Vent  with  Counterbalanced  Shutters. 

Fig.  306  indicates  a  stage  vent  proposed  by  Mr.  Freeman,  in 
which  side  vertical  shutters  are  counterbalanced  so  as  to  fall 
open  by  the  release  of  fusible  links.  A  variation  of  the  same  idea, 

Vent 

Fixed 
Skylight 


Inclined  Sash 
to  drop  to 


FIG.  307.  —  Stage  Vent  with  Inclined  Sash. 


734         FIRE    PREVENTION    AND    FIRE    PROTECTION 

but  using  inclined  sash,  weighted  at  the  top  so  as  to  make  them 
drop  horizontally  to  the  roof,  has  been  worked  out  by  Mr.  Black- 
all,  as  shown  in  Fig.  307-.  Of  the  various  types  shown,  this  is 
undoubtedly  the  best. 

Wire  Netting  under  Vents  should  never  be  used.  In  the 
Austrian  experiments  previously  described,  it  was  found  that 
such  netting  soon  caused  the  choking  of  vents  by  arresting  bits 
of  charred  paper,  scenery,  etc.  The  Boston  law  properly  re- 
quires such  netting,  if  used,  to  be  above  the  vent  opening,  but  the 
New  York  law,  in  spite  of  the  conclusiveness  of  the  Austrian 
experiments,  still  requires  the  use  of  wire  netting  immediately 
underneath  the  skylights. 

At  my  visit  to  the  remodeled  Iroquois,  I  found  the  openings 
in  their  new  ventilating  shafts  screened  by  wire  netting  in  a  way 
that  would  probably  within  a  minute's  time  put  them  into  a  con- 
dition of  uselessness  because  of  the  fragments  of  burnirer  cloth 
and  embers  with  which  they  would  be  immediately  covered  under 
the  strong  updraft,  all  of  course  with  approval  of  architect  and 
building  inspector!* 

Standard  Requirements  for  Stage  Vents,  etc.  —  There  shall  be 
one  or  more  ventilators,  constructed  of  metal  or  other  incom- 
bustible material,  near  the  center  and  above  the  highest  part  of 
the  stage  of  every  theatre,  opera  house  or  motion  picture  show, 
raised  above  the  stage  roof,  and  of  a  combined  horizontal  sec- 
tional area  equal  to  at  least  10  per  cent,  of  the  superficial  floor 
area  within  the  stage  walls.  The  openings  in  such  ventilators 
shall  have  an  aggregate  sectional  area  at  least  equal  to  that  re- 
quired for  the  ventilators.  Detailed  plans  for  the  construction 
and  operation  of  the  covers  for  the  vent  openings  must  be  ap- 
proved by  the  Superintendent  of  Buildings  before  construction 
is  begun,  and  the  entire  equipment  must  conform  to  the  follow- 
ing requirements  or  their  equivalent:  — 

The  construction  of  the  cover  and  its  operative  mechanism 
must  be  massive  and  must  open  by  force  of  gravity  sufficient  to 
effectively  overcome  the  effects  of  neglect,  rust,  dirt,  frost,  snow 
or  expansion  by  heat,  twisting  or  warping  of  the  framework. 

Glass  if  used  in  ventilators  must  be  protected  against  fall- 
ing on  the  stage.  A  wire  screen  if  used  under  the  glass  must  be 
so  placed  that  if  clogged  it  cannot  reduce  the  required  vent  area 
or  interfere  with  the  operative  mechanism,  or  obstruct  the  dis- 
tribution of  water  from  the  automatic  sprinklers. 

Cover  must  be  arranged  to  open  instantly  after  the  out- 
break of  fire  by  the  use  of  approved  automatic  fusible  links  of 
the  thinnest  metal  practicable;  manual  control  must  also  be 

Provided  by  a  cord  mm  down  to  the  stage  at  a  point  designated 
y  the  Superintendent  of  Buildings. 

*  John  R.  Freeman. 


THEATRES  735 

The  link  and  cord  must  hold  the  cover  closed  against  a 
force  of  at  least  30  pounds  excess  counterweight  tending  to  force 
the  cover  open.  The  fusible  links  must  be  placed  in  the  ventilator 
above  the  roof  line  and  at  least  in  two  other  points  in  each  con- 
trolling cord.  No  automatic  sprinkler  heads  shall  be  placed  in 
the  said  ventilator  space  above  the  roof  line.  Each  vent  cover 
shall  be  operated  at  least  daily  by  one  of  the  cords.  § 

Safety  of  Stage  Personnel.  —  Preceding  paragraphs  have 
plainly  indicated  the  dangers  to  which  performers  and  stage 
hands  are  subjected  behind  the  curtain  and  proscenium  wall. 
The  utmost  forethoughts  are,  therefore,  necessary  to  provide  for 
their  safety.  This  will  involve  the  careful  planning  of  all  dress- 
ing rooms,  fire-resisting  construction,  adequate  exits,  and  pre- 
ventive means  and  equipment. 

Dressing  rooms  should  be  isolated  from  the  stage  in  a  separate 
section  provided  for  that  purpose.  An  excellent  arrangement  is 
shown  in  Fig.  288,  illustrating  the  plan  of  the  Boston  Opera 
House.  The  walls  separating  the  dressing  room  section  from 
stage  should  be  of  brick  or  concrete,  not  less  than  8  ins.  thick,  and 
all  openings  in  same  should  be  provided  with  self-closing  fire 
doors.  Partitions  dividing  dressing  rooms,  etc.,  should  be  fire- 
resisting,  not  less  than  4  ins.  thick,  with  self-closing  fire  doors. 
All  trim  such  as  cupboards,  shelving,  etc.,  in  dressing  rooms, 
property-  or  storage-rooms  should  be  of  incombustible  material. 

At  least  two  independent  exterior  exits  shall  be  provided 
on  a  level  with  the  stage  for  the  service  of  the  stage  and  floors 
below  same.  These  exits  shall  "be  at  opposite  sides  of  the  stage. 
Each  tier  of  dressing  rooms  shall  have  an  independent  exit  lead- 
ing directly  on  to  a  fire  escape  or  to  a  court  or  street.  No  ladder 
fire  escapes  shall  be  permitted.  The  fly  galleries  shall  be  pro- 
vided with  adequate  means  of  exit.  All  exits  and  fire  escapes 
from  the  stage  section  shall  be  independent  of  the  exits  for  the 
audience  above  the  court  or  street  grade.  Stairs,  if  any,  leading 
down  from  stage  level  shall  be  enclosed  and  protected  by  fireproof 
doors.  § 

Preventive  Measures  on  Stage  include  safeguards  as  to 
lighting,  etc.,  the  so-called  fireproofing  of  scenery,  and  the  treat- 
ment of  textiles,  such  as  costumes  and  properties,  to  render  them 
flame-proof. 

As  to  lighting,  the  modern  stage  requires  a  large  amount  of 
electric  current,  and  too  much  care  cannot  be  taken  with  its  use. 
The  supply  to  stage  lights  should  be  entirely  independent  from 
the  rest  of  the  house,  so  that,  in  case  of  accident  on  stage,  the 


736         FIRE    PREVENTION    AND    FIRE    PROTECTION 

auditorium,  lobbies,  stairs,  dressing  rooms,  etc.,  need  not  be 
affected.  Fuses  are  also  generally  unreliable.  Automatic  cir- 
cuit breakers  on  circuits  of  any  size  are  far  more  dependable. 

The  fireproofing  of  scenery  by  means  of  paints  or  solutions 
and  also  the  rendering  of  textiles  "  flame-proof  "  are  discussed  in 
Chapter  XXXII. 

Equipment.  —  It  has  previously  been  pointed  out  that  ade- 
quate planning  must  include  satisfactory  fire-detecting  or  fire- 
extinguishing  equipment.  This  applies  particularly  to  the  stage 
portion.  The  occurrence  of  fire  in  the  auditorium  is  so  rare  that 
it  is  generally  considered  best  to  omit  equipment  in  that  portion 
of  the  building,  as  careless  or  excited  use  of  same  in  view  of  the 
audience  might  well  be  productive  of  more  harm  than  good. 

Equipment  of  the  stage  portion  should  include  sprinklers, 
standpipes,  and  " first  aid"  appliances. 

i  Automatic  Sprinklers  are  discussed  at  length  in  Chapter 
XXX.  As  particularly  applied  to  theatres  their  use  is  of  vital 
importance.  At  least  one  state  law,  that  of  Rhode  Island,  re- 
quires their  use  in  every  place  of  public  amusement.  Every 
state  and  city  should  require  the  same.  Their  value  has  been 
amply  attested  in  actual  theatre  fires,  as,  for  example,  in  the  fire 
in  the  Grand  Opera  House,  New  York,  November  29,  1905, 
wherein  a  stage  fire  was  so  effectually  controlled  as  to  keep  the 
loss  down  to  about  $500.*  The  only  argument  that  can  be 
advanced  against  the  use  of  sprinklers  in  theatres  is  the  one  some- 
times used  by  managers  who  claim  that  the  accidental  discharge 
of  a  head  might  cause  a  panic  in  the  audience.  But  statistics  f 
show  that  accidental  opening  is  so  remote  that  it  may  well  be 
disregarded. 

The  Installation  should  comprise  a  wet-pipe  system  in  all 
portions  of  the  building,  except  in  the  auditorium,  foyers,  lobbies, 
over  dynamos  and  switchboard,  and  above  the  roof  line  in  stage 
vents.  Where  the  water  pressure  is  ample,  city  water  supply 
with  Siamese  connection  at  sidewalk  is  sufficient.  Where  the 
city  pressure  is  low,  a  gravity  or  pressure  tank  is  necessary  as  a 
secondary  supply.  Central  station  supervision  is  desirable. 

Additional  Protection  for  the  Proscenium  Opening  has  also  been 
used  in  some  cases,  notably  in  Keith's  Theatre,  Boston,  where 

*  See  Engineering  News,  December  28,  1905. 

t  Mr.  Freeman  gives  a  proportion  of  one  sprinkler  leak  in  each  60,000  heads 
per  year. 


THEATRES 


737 


308.  —  "Regan" 
Nozzle 


" Regan"  nozzles  are  installed, — one  at  center  of  stage  just 

inside  the  curtain  line,  covered  by  a  loose  cast-iron  floor  plate 

which   would   be  raised   automatically  by 

the  water  pressure,  —  and  one  at  each  side 

of  the  proscenium  arch,  halfway  up.      The 

general  appearance  of  a   " Regan"   nozzle 

is  shown  in  Fig.  308.      From  a  test  made 

at  the  Mason  St.  Engine  House  in  Boston, 

the   author  believes  that  nozzles   used   as 

above    described   would    form    a    valuable 

auxiliary  protection  to  the  fire  curtain. 

Mr.  Sachs  mentions  the  use  in  certain 
London  theatres  or  music  halls  of  sprinkler 
attachment  to  the  fire  curtain,  so  arranged 
that  the  operation  of  the  curtain  releases 
sprinkler  heads  placed  over  the  proscenium  arch.  A  similar 
sprinkler  water  curtain  is  installed  in  Keith's  Theatre,  Boston, 
in  addition  to  the  Regan  nozzles  and  regular  sprinkler  equipment 
over  stage.  The  water  curtain  is  controlled  by  a  wheel  valve 
immediately  adjoining  the  curtain  pull  and  switch  board. 

Standpipes  are  more  fully  described  in  Chapter  XXXIV. 
For  theatre  application,  the  following  is  recommended : 

Standpipes  shall  be  provided  not  less  than  4  inches  in  diam- 
eter of  wrought-iron  or  galvanized-stee  1  with  hose  connections, 
located  as  follows:  One  on  each  side  of  the  stage  on  each  tier, 
one  readily  accessible  from  the  property  room,  the  carpenter  shop, 
scenery  storage  rooms,  lobby  and  elsewhere  as  may  be  required 
by  the  Fire  Department.  These  standpipes  together  with  fittings 
and  connections  shall  be  of  such  strength  as  safely  to  withstand 
at  least  300  pounds  water  pressure  to  the  square  inch  when  in- 
stalled and  ready  for  service  without  leakage  at  joints,  valves  or 
fittings,  and  shall  be  provided  with  hose  connections  fitted  with 
approved  straight  composition  gate  valves  at  hose  outlets.  § 

"First  Aids"  on  Stage.  — The  great  value  of  "first  aid" 
fire  protection  appliances  and  the  details  of  their  use  are  discussed 
in  Chapter  XXXII.  For  particular  use  in  theatres,  the  following 
requirements  should  be  followed : 

There  shall  be  on  each  side  of  the  stage  two  axes,  one 
twenty-foot,  one  fifteen-foot  and  one  ten-foot  hook,  as  designated 
by  the  Fire  Department.  On  each  side  of  the  stage,  under  the 
stage,  on  each  fly  gallery,  also  in  property  and  other  storerooms, 
and  in  each  workshop  there  shall  be  kept  in  readiness  for  imme- 
diate use  one  approved  carbonic  acid  gas  two-and-one-half  gallon 


738         FIRE    PREVENTION    AND    FIRE    PROTECTION. 

hand  fire  extinguisher  and  one  forty-gallon  cask  filled  with  water, 
and  six  fire  pails;  said  casks  and  buckets  shall  be  painted  red 
and  lettered  '  For  Fire  Purposes  Only.'  There  shall  also  be  pro- 
vided at  least  three  approved  carbonic  acid  gas  two-and-one-half 
gallon  hand  fire  extinguishers  for  each  tier  of  the  auditorium. § 

Roof  Protection  for  theatres,  as  for  all  other  important  build- 
ings, is  distinctly  advisable,  in  case  of  conflagration  or  fire  in 
adjoining  property.  The  standpipes  should  preferably  be  con- 
tinued to  the  roof  as  explained  in  Chapter  XXXIV,  and  hose, 
nozzles,  couplings,  lanterns  and  ropes  are  valuable  accessories 
in  a  roof  house  or  weather-proof  locker. 

Inspection  and  Maintenance.  —  In  addition  to  any  regular 
inspections  which  may  be  made  by  the  building-  or  fire-depart- 
ment or  by  underwriters,  a  systematic  inspection,  preferably 
weekly,  should  be  made  by  the  management.  Such  inspections 
should  be  reported  on  especially  prepared  blanks,*  and  should 
cover,  in  full  detail,  all  parts  of  the  sprinkler  system,  especially 
valves  (unless  fitted  with  central  station  supervision),  —  all 
appliances,  such  as  pails,  extinguishers,  standpipes  and  hose,  — 
and  all  constructive  features  such  as  fire  doors,  exit  locks  or 
hardware,  egress  passages,  fire  curtain  operation,  stage  vents, 
and  orderly  premises.  For  further  information  concerning  the 
inspection  and  maintenance  of  fire  protection  devices,  see 
Chapter  XXXVI. 

Fire  Duties  and  Fire  Drills  are  both  especially  important  in 
theatres.  All  employees,  particularly  stage  hands,  should  be 
well  drilled  as  to  stations  and  duties  in  case  of  fire.  Further 
information  concerning  private  fire  departments  is  given  in 
Chapter  XXXV. 

Fire  drills,  with  especial  reference  to  the  handling  of  an  audi- 
ence in  time  of  emergency,  are  considered  in  detail  in  Chapter 
XXXVII. 

Construction.  —  All  theatres  and  similar  buildings  should, 
of  course,  be  of  thoroughly  fire-resisting  construction.  In  addi- 
tion to  parts  of  building  previously  mentioned,  the  following 
should  invariably  be  made  fire-resisting,  —  all  that  portion  of 
stage  which  is  not  movable,  or  all  except  the  part  embraced 
between  proscenium  jambs  and  from  proscenium  to  rear  wall,  — 

*  For  suggested  forms  see  "On  the  Safeguarding  of  Life  in  Theatres,"  by 
John  R.  Freeman,  also  Report  No.  XIV  of  the  Insurance  Engineering  Experi- 
ment Station. 


THEATRES  739 

roof,  —  and  fly-galleries.  The  grid  should  be  made  of  iron, 
slatted,  or  in  form  of  gratings.  Floors  should  be  of  cement  or 
other  incombustible  material. 

Costs.  —  Fire-resisting  theatres  cost  -  from  eighteen  to  fifty 
cents  per  cubic  foot.  An  average  for  first-class  construction 
under  the  Boston  law  is  about  thirty  cents  per  cubic  foot. 


CHAPTER  XXIII. 

SCHOOLS. 

The  Fire  Hazard  in  Schools  concerns 

1.  Danger  to  life,  2.  Danger  to  the  building,  and  3.  Danger 
to  surrounding  property. 

Danger  to  Life.  —  In  schools,  exactly  the  same  as  in  theatres, 
the  life-safety  of  the  occupants  is  the  first  essential.  In  other 
words,  every  consideration  of  design  or  construction  must  be 
subordinated  to  secure,  above  all  else,  the  quick  emptying  of 
the  building. 

As  a  result  of  the  Iroquois  Theatre  fire,  great  improvements 
have  been  made  during  recent  years  in  theatre  design  and  con- 
struction; but,  notwithstanding  such  terrible  examples  as  the 
Collinwood  school  disaster,  —  wherein  173  children  lost  their 
lives  and  a  $60,000  building  was  destroyed  simply  because  the 
boiler  room  was  not  cut  off  from  the  rest  of  the  structure  in  a 
thoroughly  fire-resisting  manner,  —  almost  criminal  laxness  still 
prevails  in  the  design  and  construction  of  very  many  buildings 
devoted  to  educational  purposes,  such  as  schools,  colleges  and 
asylums.  The  same  is  largely  true  of  much  hospital  and  hotel 
construction  —  particularly  summer  or  resort  hotels. 

Danger  to.  the  Building.  —  There  is  a  distinct  fire  danger  in 
school  buildings,  owing  to  the  fact  that  such  structures  are  vacant 
so  much  of  the  time.  An  analysis  of  the  fire  record  of  school 
and  college  buildings,  etc.,  shows  that  a  far  greater  number  of 
fires  occur  annually  in  this  class  of  buildings  than  is  popularly 
supposed.  Thus,  from  compilations  made  by  The  Insurance 
Press,  it  appears  that  no  less  than  58  fires  occurred  in  buildings 
devoted  to  educational  purposes  in  the  United  States  and  Canada 
for  the  first  three  months  of  the  year  1908.*  These  included 
fires  in  public  school  buildings  scattered  throughout  eighteen 
states,  and  in  dormitories,  etc.,  in  twenty  states. 

The  Danger  to  Surrounding  Property  induced  by  an  inflammable 
schoolhouse,  or,  indeed,  by  any  other  building  of  such  public 
*  See  The  Insurance  Press,  April  22,  1908. 

740 


SCHOOLS  741 

ownership,  is  in  distinct  contravention  to  that  civic  responsi- 
bility which  applies  with  even  greater  force  to  the  community 
than  to  individuals. 

Types  of  School  Buildings  comprise: 

1.  Wooden  buildings, 

2.  Those  with  masonry  walls  and  wood  joist  construction,  and 

3.  Fire-resisting  buildings. 

Wooden  School  Buildings  should  be  strictly  confined  to 
country  districts,  and  should  never  exceed  one  story  in  height. 
In  localities  where  such  construction  would  be  used,  land  values 
will  never  be  high  enough  to  warrant  assuming  the  dangers  of 
building  to  a  height  of  more  than  one  story. 

If  the  building  is  heated  by  stoves,  they  should  be  placed 
in  plain  sight,  —  as  is  done  in  a  portable  school,  —  while  a  heater 
or  boiler  should  invariably  be  placed  in  a  basement  or  other 
separate  compartment  having  fire-resisting  walls  and  ceiling,  and 
all  openings  properly  protected,  as  described  under  the  following 
type  of  building. 

Schools  with  Masonry  Walls  and  Wood  Joist  Construc- 
tion should  be  confined  to  small  towns  or  sparsely  settled  sub- 
urbs, and  should  be  limited  to  two  stories  in  height. 

Planning  should  especially  consider  stairs,  fire  escapes,  exits, 
etc.,  as  described  later  for  fire-resisting  buildings.  Even  when 
the  building  is  but  two  stories  in  height,  as  here  recommended, 
these  features  of  planning  become  of  the  first  importance. 

Construction.  —  All  stairways  and  corridors  should  be  built  of 
fire-resisting  materials,  and  the  boiler  room,  if  not  the  whole 
basement,  should  be  absolutely  cut  off  from  the  balance  of  build- 
ing, as  described  in  the  following  paragraph.  In  addition  to 
these  requirements,  however,  the  fire-safety  of  the  building  may 
be  materially  improved,  at  little  expense,  if  the  construction 
incorporates  the  safeguards  enumerated  in  Chapter  XXIV  as 
particularly  applicable  to  residences.  See,  especially,  para- 
graphs "  Fire  Safeguards  applicable  to  Ordinary  Construction  " 
and  "  Chimneys  and  Flues,"  page  759,  —  "  Fire  Stops,"  p.  763, 
—  and  "  Basement  Ceilings,"  page  765. 

Boiler  Rooms,  etc.  —  The  principal  fire  dangers  in  school  build- 
ings exist  in  heating  apparatus,  storage  rooms,  or  closets  not  often 
used.  These  features  of  design  are  almost  invariably  relegated 
to  the  basement;  hence  the  adequate  cutting  off  or  isolation  of 
such  features  becomes  of  great  importance. 


742          FIRE    PREVENTION    AND    FIRE    PROTECTION 

If  absolute  fire  protection  is  desired,  or  if  boilers  under  pressure 
are  used  for  power,  theory  would  require  locating  the  heating 
or  power  plant  outside  the  building;  but  such  practice  would 
entail  additional  expense  which,  except  for  the  danger  of  possible 
boiler  explosions,  would  not  usually  be  justified  from  a  practical 
standpoint. 

Boiler-  and  storage-rooms,  etc.,  should,  however,  invariably 
be  cut  off  from  the  balance  of  the  building  by  thoroughly  fire- 
resisting  walls,  preferably  of  brick  or  concrete;  and  such  roonn 
should  have  the  fewest  possible  openings  into  the  rest  of  the 
building,  and  these  openings  should  be  provided  with  automat- 
ically closing 'fire-resisting  doors. 

The  floors  over  boiler-  and  storage-rooms,  etc.,  should  pref- 
erably be  of  thoroughly  fire-resisting  construction,  but,  if  ordi- 
nary wood  joist  construction  is  used,  for  economy,  the  spaces 
between  the  joists  should  at  least  be  filled  in  solid  with  hollow 
tile,  concrete,  mortar  or  mineral  wool.  The  considerable  resist- 
ance to  fire  offered  by  wood  studs  (or  joists)  filled  in  between 
with  hollow  tile  blocks,  is  referred  to  in  Chapter  XXIV,  page  767. 

Stamped  metal  or  corrugated-iron  ceilings,  or  even  metal  lath 
and  plaster  ceilings  below  wood  joists  —  are  not  adequate  protec- 
tions. Such  makeshifts  not  only  leave  open  spaces  in  the  thick- 
ness of  the  floor,  but  are  also  liable  to  be  rendered  ineffectual 
through  the  presence  of  holes. 

Cooking  and  Manual  Training  Rooms  also  possess  distinct  fire 
hazards  which  should  be  given  due  consideration  in  determining 
the  surrounding  construction. 

Fire  Alarm  Signals,  Fire  Drills,  and  "First  Aid"  Appliances 
are  described  later.  These  features  are  especially  essential  in 
schools  other  than  thoroughly  fire-resisting. 

Fire-resisting  Schools.  —  Schools  in  cities,  or  in  any  closely 
settled  district,  should  be  of  fire-resisting  construction  throughout. 

Location.  —  School  buildings,  especially  in  cities,  should  be 
located  so  as  to  secure  the  least  possible  exposure  hazard,  not  only 
on  account  of  avoiding  fire  damage  through  the  burning  of  adja- 
cent buildings,  but  also  on  account  of  possible  panic  through  fire 
or  explosion  in  such  buildings.  This  would  suggest  the  inadvisa- 
bility  of  locating  schools  adjacent  to  or  even  very  near  manufac- 
turing, frame  or  other  buildings  constituting  a  serious  menace. 

On  the  other  hand,  too  great  reliance  should  not  be  placed 
upon  suitable  or  isolated  location.  In  the  case  of  country  or 


SCHOOLS 


743 


suburban  school  buildings  far  more  thought  has  generally  been 
given  to  location,  light,  air  and  recreation  space  than  to  con- 
struction with  reference  to  internal  fire  hazard. 

Height.  —  Fire-resisting  schools  should  preferably  never  exceed 
three  stories  in  height.  Schools  five  or  six  stories  high,  as  in  New 
York  City  and  in  some  other  large  centers  of  population,  are  the 
outcome  of  special  conditions,  and  should  not  serve  as  precedents. 


FIG.  309.  —  Basement  Plan,  Lyman  District  School,  East  Boston. 


Planning.*  —  It  has  previously  been  stated  that  the  planning 
of  schoolhouses,  like  theatres,  should  primarily  consider  life 
safety  —  i.e.,  the  quick  emptying  of  the  structure.  To  this  end, 
I  the  planning  and  construction  of  corridors,  stairways,  fire  escapes 
and  exits,  all  become  of  the  first  importance.  The  location  of 
the  general  assembly  hall,  if  used,  is  also  vital. 

*  The  Boston  Board  of  Schoolhouse  Commissioners,  especially  under  the 
able  guidance  of  Mr.  R.  Clipston  Sturgis,  Architect,  and  formerly  Chairman  of 
the  Board,  has  done  notable  work  in  formulating  and  directing  schoolhouse 
design  and  construction.  Much  valuable  general  information  regarding 
"Standard  Requirements  for  School  Buildings  and  Yards,"  etc.,  may  be  found 
in  the  "Annual  Reports  of  the  Schoolhouse  Department."  These  may  be 
obtained  by  addressing  that  Department  at  120  Boylston  St.,  Boston,  Mass. 


744 


FIRE    PREVENTION    AND    FIRE    PROTECTION 


Stairways.  —  In  addition  to  the  data  previously  given  as  to 
the  design,  capacity  and  construction  of  stairs  and  fire  escapes 
in  Chapters  XV  and  XXII,  severalpoints  in  connection  with  .the 
design  of  such  means  of  egress  in  schoolhouses  and  like  buildings 
are  worthy  of  further  consideration. 

Capacity.  —  Where  fire  drills  are  required  at  frequent  intervals, 
-*-  as  is  now  general  in  most  city  schools,  —  it  will  be  found  that 


FIG.  310.  —  First  Floor  Plan,  Lyman  District  School,  East  Boston. 


the  data  recommended  for  use  in  determining  the  quick  emptying 
possibilities  of  stairway  capacity  may  safely  be  modified.  The 
occupants  of  general  mercantile  buildings,  hotels,  theatres,  etc., 
are  constantly  changing  day  by  day,  so  that  fire  drills  in  such 
buildings  are  of  principal  value  to  the  regular  employees,  — 
while  in  schools,  where  the  occupancy  is  fairly  constant  through- 
out the  year,  familiarity,  practice  and  discipline  may  accomplish 
remarkable  results  in  quick  emptying  tests  with  stair  capacities 
not  to  be  recommended  in  other  types  of  buildings.  A  maximum 
stair  capacity  under  drill  conditions  may  be  determined  by  the 
working  rule,  derived  from  experience,  that  not  more  than  120  per- 
sons in  lines  two  abreast  can  well  pass  a  given  point  per  minute. 


SCHOOLS 


745 


The  " Rules  for  Fire  Protection"  in  the  public  schools  of  the 
City  of  New  York  require  as  follows : 

Each  building  shall  have  a  sufficient  number  of  fireproof 
stairways  and  of  exits  to  permit  of  its  occupants  vacating  same 
in  not  more  than  three  minutes  in  non-fireproof  and  not  to  exceed 
three  and  one-half  minutes  in  fireproof  structures. 

Location.  —  To    make   such    quick    emptying   testa   possible, 
however,  stairways  should  be  located  with  this  distinct  object  in 


THJ 


FIG.  311.  —  Second  Floor  Plan,  Lyman  District  School,  East  Boston. 

view.  This  requires  that  what  might  be  termed  "simple"  and 
" progressive"  egress  must  be  studied,  as  contrasted  with  " in- 
volved" and  " congested"  egress. 

"Simple"  egress  requires  straight  corridors,  giving  a  clear 
view  of  the  stairway  to  be  used,  so  that  no  excuse  may  exist  for 
the  crowding  or  panic  which  may  easily  result  in  an  "involved" 
plan  wherein  classes  are  held,  awaiting  their  turn,  in  rooms  or 
corridors  around  corners,  or  out  of  sight,  from  the  other  moving 
classes.  "Progressive"  egress  requires  that  stairways  be  placed 
at  the  ends  rather  than  at  the  centers  of  corridors,  so  that  classes 
may  leave  their  rooms  in  a  progressive,  prearranged  order. 


746         FIRE   PREVENTION   AND   FIRE   PROTECTION 

Where  stairways  are  placed  at  interior  corners  (as  in  Fig.  312), 
or  centrally  on  corridors,  congested  conditions  are  liable  to  ensue. 
An  example  of  simple  and  progressive  means  of  egress  is  shown 
in  Figs.  309,  310  and  311,  which  illustrate  the  basement,  first  and 
second  floor  plans  respectively  of  the  elementary  grade  Lyman 
District  School,  East  Boston.  A  less  successful  planning  of 
means  of  egress  is  shown  in  Fig.  312  which  illustrates  the  second 


FIG.  312.  —  Second  Floor  Plan,  Stuyvesant  High  School,  N.  Y. 

floor  plan  of  the  Stuyvesant  High  School,  New  York  City.  The 
detailed  construction  of  the  stair  shown  in  this  plan  is  considered 
in  a  following  paragraph. 

All  stairs  should  discharge  directly  to  outside  of  building,  and 
not  into  corridors,  passages,  etc. 

Construction.  —  Stairs  should  be  of  iron  or  concrete  construc- 
tion. If  of  the  former,  2-inch  North  River  stone  treads  and 
landings  are  found  to  be  economical  as  to  wear  and  satisfactory 


SCHOOLS  747 

as  to  non-slipping  requirements.  If  of  concrete  construction, 
granolithic  surface  treads  and  platforms  should  be  used. 

The  rise  of  steps  should  be  6|  or  7  inches,  to  lOj-inch  treads. 

The  runs  should  not  be  over  5  feet  wide,  to  accommodate  two 
abreast,  as  any  width  over  this  will  serve  rather  to  invite  crowd- 
ing than  contribute  to  ease  or  comfort. 

Wall  handrails  are  considered  essential  by  some  authorities, 
and  superfluous  by  others.  Observation  shows  that  most  chil- 
dren, even  the  littlest,  disregard  their  presence. 

Isolated  Stairs.  —  In  a  fuller  discussion  of  stairs  and  stair 
enclosures  in  Chapter  XV,  the  general  advisability  of  providing 
isolated  stairways,  —  that  is,  stairways  cut  off  from  corridors  by 
fire-resisting  partitions,  —  has  been  pointed  out.  This  principle 
has  been  carried  out  in  a  number  of  school  buildings,  but  not 
always  without  criticism. 

A  typical  stairway  which  has  been  largely  used  in  the  newer 
schools  of  greater  New  York,  and  which  has  been  developed  by 
Mr.  C.  B.  J.  Snyder,  Architect  to  the  New  York  Board  of  Educa- 
tion, is  shown  in  Fig.  313.  (The  relation  of  these  stairs  to  the 
rest  of  the  floor  plan  is  shown  in  Fig.  312.)  This  arrangement 
illustrates  two  separate  features  of  design,  viz.,  isolation,  and  the 
"double"  stairway.  Neither  feature  is  necessarily  dependent 
on  the  other. 

The  isolation  of  the  stairs  is  effected  by  the  use  of  iron  and 
rough  wire  glass  screens  or  enclosures  which  extend  from  floors 
to  ceilings  at  the  corridor  lines.  The  entrances  to  the  landings 
are  closed  with  fire  doors  which  are  provided  with  automatic 
check  and  spring.  A  similar  metal  and  glass  partition  separates 
the  double  system  of  runs. 

For  large  school  buildings  of  more  than  three  stories  in  height, 
this  isolation  of  stairways  is  both  practical  and  wise;  but  for 
fire-resisting  schools  of  three  stories  or  less,  as,  for  example, 
in  the  three  story  school  shown  in  plan  in  Fig.  314,  the  nec- 
essity or  even  the  advisability  of  isolation  is  very  questionable. 
Data  given  in  a  later  paragraph  concerning  fire  drills  show  that 
schools  may  be  emptied  in  such  short  time  that  the  introduction 
of  separating  screens  or  partitions  at  stairways  may  well  be 
superfluous,  or  even  objectionable,  in  that  they  may  cause  more 
obstruction  or  congestion  than  is  warranted  by  the  advantages 
of  such  isolation.  This  line  of  reasoning  is  only  valid,  however, 
when  fire  drills  are  regularly  practiced. 


748 


FIRE    PREVENTION    AND    FIRE    PROTECTION 


Double  Stairways.  —  In  Fig.  313  it  will  be  noted  that  the 
stairwell  contains  two  separate  and  independent  stairs,  the  de- 
scending run  of  one  adjoining  the  ascending  run  of  the  other. 


Down 


•r  Door 


:n  — 

(c 

-*- 

/ 

| 

1 

rire 

la^s 

gai 

; 

-«- 

—  U 

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—  1 

-1 

Ln 

-i 

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-Down 


Door"ll» 


Metal  and  Wire  Glass  Part, 
FIG.  313.  —  Double  Stairs  in  Stuyvesant  High  School,  N.  Y. 

Landings  are  provided  at  the  floor  levels,  and  platforms  midway 
between.  This  arrangement  is  made  possible  only  by  the  use 
of  a  15  ft.  6  in.  story  height  from  floor  to  floor,*  —  in  order  to 
obtain  the  necessary  headroom,  —  so  that  the  increased  cost  of 

*  The  standard  story  height  for  Boston  schools  is  13  ft.  6  ins. 


SCHOOLS 


749 


all  walls  and  partitions  will  usually  more  than  offset  the  saving 
effected  in  floor  area. 

Corridors,  Exits,  etc.  —  Schoolrooms  should  preferably  have 
but  one  door  opening  into  the  corridor.  Experience  has  shown 
that,  where  two  doors  exist  —  as  where  one  opens  from  class- 
room and  a  second  from  the  adjoining  wardrobe  —  teachers  often 
have  great  difficulty  in  exercising  that  complete  control  over  the 
egress  of  the  children  which  is  essential  to  prevent  panic  and  to 
maintain  the  discipline  of  the  fire  drill.  It  will  be  noted  in  Fig. 


D  DOD  D  DO 
0  D  Q.Q  D  D  D 
D  D 

o 

Q  Q&'x  30j  Q 

D  D  D  D  D  DO 


D  D  D  D  D  D  D 
DO  D  D  ODD 
Q  cOJassj  o  D 
D  P0QPS  D  D 
0fiXl3fira  D 
D  D  Q  D  CIQ  D 


S  o  D 

D  D     QPIPG  D 
D  Q2.4'ix  80tf  D 

a  a  Q  a  D  D  a 


FIG.  314.  —  Three  Story  Schoolhouse  with  Isolated  Stairs. 

311  that  all  classrooms,  save  one,  have  but  one  door  connecting 
with  the  corridor. 

Corridors  should  be  not  less  than  8  feet  wide  for  four  school- 
rooms on  a  floor,  and  not  less  than  10  feet  wide  for  more  than 
four  rooms  per  floor.  Walls  should  be  of  fire-resisting  construc- 
tion, as  of  a  light  colored  glazed  brick,  and  floors  should  be  of 
terrazo  or  similar  material. 

Exit  Doors,  opening  directly  to  the  open  yard  or  street,  should 
be  provided  at  or  near  the  foot  of  all  stairways.  An  excellent 
arrangement  is  shown  in  Fig.  309,  wherein  the  exit  doors  — 
serving  for  entrance  also  —  are  placed  at  the  level  of  the  lowest 
intermediate  stair  landing.  Experience  has  shown  that,  par- 
ticularly for  children,  special  emergency  exit  doors  are  inadvis- 
able. 

All  exit  doors,  whether  from  corridors,  stairways,  or  at  the 
foot  of  enclosed  exterior  fire  escapes,  should  invariably  swing 
outward,  and  be  provided  with  either  spring  locks  which  can 


750 


FIRE    PREVENTION    AND    FIRE    PROTECTION 


always  be  opened  from  the  inside  without  the  use  of  key,  or  with 
safety  door-push  device,  as  described  for  theatre  doors  in  the 
previous  chapter.  Hardware  to  hold  doors  open  in  case  of 
emergency  should  also  be  provided. 

Assembly  Halls  should  be  placed  on  the  ground  floor.  The 
exit  door  or  doors  should  lead  directly  to  the  outside,  —  as  in 
Fig.  310,  —  or  else  the  corridors  connecting  to  stairs  should  be 
ample,  short,  and  as  simple  and  direct  as  possible. 


FIG.  315. —  First  Floor  Plan,  Mozart  School,  Chicago. 

The  practice  of  placing  assembly  halls  on  the  top  floors  of 
school  buildings,  in  order  to  remove  them  from  the  more  used 
lower  classroom  stories,  is  generally  being  discontinued  in  the 
best  present-day  design  for  two  reasons,  —  first,  because  of  the 
fire  danger  to  audiences  congregated  on  upper  floors,  and  second, 
because. of  the  growing  use  of  assembly  halls  for  civic  gatherings 
or  purposes  not  directly  connected  with  school  functions.  In 
the  newer  Chicago  schools,  the  assembly  halls  —  often  used  for 
gymnasium  purposes  also  —  are  located  in  one-story  wings  which 


SCHOOLS 


751 


are  placed  at  the  front  of  the  building  at  the  ground  floor  level. 
No  basements  are  used,  but  the  ground  floor  is  placed  a  step  or 
two  above  the  yard  level.  The  first  and, second  floor  plans  of  the 
new  Mozart  School,  Chicago,  are  shown  in  Figs.  315  and  316 
respectively.  The  third  floor  plan  is  practically  the  same  as  the 
second  floor.  It  should  be  noticed  that  the  boiler  room  is  also 
located  in  a  one-story  wing. 


FIG.  316.  —  Second  Floor  Plan,  Mozart  School,  Chicago. 


Fire  Escapes.  —  It  has  been  shown  in  Chapter  XV  that,  as 
a  means  of  rapid  egress  for  any  considerable  number  of  people, 
outside  fire  escapes  are  not  comparable  to  inside  stairways.  If, 
however,  they  are  required  as  an  auxiliary  means  of  exit  on  either 
old  or  new  school  buildings,  a  type  may  be  selected  from  those 
previously  described.  If  the  balcony  and  stair  plan  is  used,  the 
design  should  preferably  call  for  short,  easy  runs,  not  steeper 
than  45  degrees,  with  frequent  landings.  The  spaces  from 
handrails  down  to  strings  are  best  filled  in  with  stout  wire-mesh 
panels. 


752 


FIRE   PREVENTION   AND   FIRE   PROTECTION 


As  a  means  of  ready  access  for  firemen,  so  that  they  may 
quickly  reach  upper  floors  to  aid  straggling  or  panic  stricken 
children  without  interfering  with  the  egress  in  progress  by  the 
stairs,  exterior  fire  escapes  may  easily  prove  of  great  value. 
Where  interior  stairways  are  fairly  ample,  and  where  the  fire  drill 
is  practised,  access,  in  the  opinion  of  most  city  firemen,  forms  the 
principal  argument  in  favor  of  fire  escapes.  In  second  class  con- 
struction the  function  of  fire  escapes  as  dependable  means  of 
egress  assumes  far  more  importance. 

Construction.  —  The  details  of  walls,  floors,  partitions,  col- 
umn protections,  etc.,  require  no  special  methods  of  treatment  not 
covered  by  previous  chapters,  except,  possibly,  in  the  case  of  all- 
concrete  school  buildings  of  which  an  increasing  number  are  being 
built  with  apparent  success.  For  a  description  of  concrete  schools 
built  in  several  cities  and  towns  in  New  Jersey,  see  "  Reinforced 
Concrete  Schools"  by  Mr.  John  T.  Simpson,  "1911  Proceedings 
of  the  National  Association  of  Cement  Users." 

Fire  Alarm  System.  —  A  most  important  requirement  in 
every  school  building  is  some  approved  form  of  fire  alarm  system. 
This  should  be  so  arranged  as  to  fulfil,  with 
the  utmost  reliability  and  simplicity,  two 
separate  functions,  viz.,  the  drill  alarm,  and 
the  auxiliary  alarm  in  case  of  fire,  to  fire  de- 
partment headquarters.  The  system  should 
be  capable  of  giving  the  drill  alarm  sepa- 
rately, but  the  auxiliary  alarm  must  be  ar- 
ranged invariably  to  include  the  gong  alarm 
also. 

The  fire  alarm  system  which  is  now  used  in 
Boston  schools,  and  which  has  been  brought 
to  a  high  point  of  perfection  by  Mr.  Benja- 
min B.  Hatch,  Electrical  Engineer  of  the 
Boston  Schoolhouse  Department,  may  be 
briefly  described  as  follows: 

The  signal  stations,  illustrated  in  Fig.  317, 
are  generally  placed  one  on  each  floor  and 
one  at  the  outer  vestibule  or  at  main  en- 
trance door. 

To  use  the  station  for  fire  drill,  the  door  is  opened  by  turning 
the  T-handle,  and  the  inside  lever  is  pulled  down  once  and  let 
go.  This  sounds  the  regulation  fire  drill  alarm  on  the  gongs,  viz.. 


FIG.  317. —  Fire  Alarm 
Signal  Station  as  used 
in  Boston  Schools. 


SCHOOLS  753 

4-4,  without  calling  the  fire  department.  If  the  door  is  not 
closed  immediately,  the  "disarrangement"  bell  in  the  janitor's 
room  rings  continuously  until  the  door  is  closed. 

In  case  of  fire,  the  small  hammer  hanging  to- the  box  is  used  to 
break  the  glass  in  the  door.  The  lever  within  the  opening  (which  is 
different  from  the  drill  alarm  lever)  is  then  pulled  down  once,  and 
let  go.  This  transmits  the  signal  to  the  fire  department,  and  also, 
through  a  connection  between  the  outer  and  inner  levers,  causes 
the  gongs  in  the  building  to  sound  the  regular  drill  signal,  4-4. 

The  gongs  —  placed  one  or  two  on  each  floor,  according  to 
size  of  building  and  arrangement  of  corridors  —  are  electro- 
mechanical, i.e.,  the  striking  mechanism  is  driven  by  a  powerful 
spring  which  is  controlled  by  an  electro-magnet  connected  to 
the  box  circuit.  The  gongs  will  strike  about  500  blows  with  one 
winding,  but  a  circuit  breaker  attachment  on  the  gongs  will  cause 
the  " disarrangement "  bell  in  the  janitor's  room  to  ring  after  the 
gong  has  struck  420  blows.  This  bell  will  continue  ringing  until 
the  gong  is  wound. 

Fire  Drills.*  —  In  Boston  schools,  fire  drills  are  required  at 
least  once  a  month,  in  addition  to  which,  at  the  option  of  the 
master,  a  second  is  usually  given.  These  are  invariably  without 
notification  to  either  scholars  or  teachers.  No  drill  master  is 
employed,  but  the  procedure  of  the  drills  is  left  to  the  judgment 
and  experience  of  the  master  and  teachers.  Wraps  are  dis- 
regarded in  mild,  fair  weather,  but  are  put  on  in  severe  weather. 
The  following  data  from  records  of  the  Schoolhouse  Department 
show  some  of  the  remarkable  results  which  are  obtained. 


Type  of  school. 

Number  of  pupils. 

Elapsed  time. 

Boys 

800 

1  min   50  sec 

Mixed. 

725-750 

1  min.  10  sec. 

Primarv  

400,  in  columns  of  4 

1  min.  25  sec. 

School  for  deaf  children. 

225 

1  min.    2  sec. 

In  one  instance  where  a  fire  occurred  during  school  hours,  700 
pupils  were  dismissed  in  perfect  order  and  were  all  outside  the 
building  when  the  fire  apparatus  arrived. 

"First  Aid"  Appliances  should  include  a  reasonable  supply 
of  three-gallon  chemical  extinguishers,  as  such  means  are  often 
sufficient  to  handle  incipient  fires.  Both  teachers  and  pupils, 

*  For  suggestions  covering  organization,  etc.,  of  fire  drills  in  schools,  see 
page  1006. 


754         FIRE    PREVENTION    AND    FIRE    PROTECTION 

however,  should  insistently  be  instructed  to  ring  in  the  fire  alarm 
fir sty  and  then  to  combat  the  fire  if  such  course  seems  advisable. 

Cost  of  School  Buildings.  —  The  following  table  gives  the 
costs  of  certain  Boston  schools  which  have  been  built  of  second- 
class  construction,  —  i.e.,  with  brick  exterior  walls  and  wooden 
floors,  roofs,  partitions,  etc.,  —  and  of  certain  Boston,  Chicago 
and  St.  Louis  Schools  which  have  been  built  of  first-class  or 
fire-resisting  construction.  In  comparing  the  costs  per  cubic 
foot  or  per  pupil  for  the  fire-resisting  schools,  the  following  in- 
formation is  pertinent. 

Boston.  —  Buildings  are  of  fire-resisting  construction  through- 
out, except  those  schools  designated  as  having  wooden  roofs. 
All  of  these  schools  except  the  Nathan  Hale  and  the  Peter  Faneuil 
contain  cooking  and  manual  training  rooms  (included  in  the 
number  of  classrooms  given),  and  assembly  halls.  The  costs  of 
the  buildings  include  heating  and  ventilating,  lighting,  telephones, 
electric  clocks,  fire  alarm  system  and  all  necessary  fixed  equip- 
ment except  shades.  Classrooms  are  finished  complete  except 
desks  and  teacher's  chair.  Wardrobes  include  hat-,  coat-  and 
umbrella-racks.  Manual  training  rooms  are  complete  except 
benches  and  teacher's  desk.  Cooking  rooms  are  completely 
equipped  with  teachers'  coal-  and  gas-ranges,  individual  gas 
ranges  for  pupils,  dressers,  sinks,  etc.  Assembly  hall  seats  are 
not  included.  "One  must  bear  in  mind  that  few  cities  build  and 
equip  as  thoroughly  as  Boston,  and  that  nearly  all  school  build- 
ings have  grounds  about  them  which  are  finished  for  use  by  the 
pupils,  the  cost  of  which  is  included."  5 

Chicago.  —  All  of  the  Chicago  schools  listed  have  been  de- 
signed and  superintended  by  Mr.  A.  F.  Hussander,  Acting 
Architect  to  the  Board  of  Education.  The  buildings  are  uni- 
formly of  fire-resisting  construction,  with  masonry  walls  faced 
with  pressed  brick  and  cut-stone  trimmings,  —  hollow  tile  floor 
arches  and  partitions,  —  fire-resisting  attics  and  roofs,  —  asphalt 
floors  in  corridors  and  toilets,  —  clear  maple  floors  in  classrooms, 
—  oak  finish,  —  and  iron  stairs  with  asphalt  treads.  The  cost 
includes  heating  and  ventilating,  plumbing,  electric  lighting, 
heat  regulation,  shades,  blackboards,  bookcases,  teachers'  ward- 
robes, and  office  and  library  cases. 

Desks,  tables,  seats  and  chairs  are  purchased  separately  in 
wholesale  quantities  by  the  Board  of  Education,  and  are  placed 

*  "  1910  Annual  Report  of  the  Boston  Board  of  Schoolhouse  Commissioners." 


SCHOOLS 


755 


756         FIRE   PREVENTION   AND   FIRE   PROTECTION 

as  required.  The  equipment  of  a  twenty-four  room  elementary 
school  building,  including  desks.,  chairs,  assembly  hall  seats, 
gymnasium  apparatus,  household  arts  tables,  manual  training 
benches,  etc.,  will  approximate  from  $4000  to  $5000  in  cost. 

All  of  these  schools  here  listed  are  three  stories  high  without 
basements,  and  all  contain  assembly  halls,  gymnasiums,  manual 
training  and  household  arts  rooms,  in  addition  to  the  class  rooms 
listed.  The  Waters  School  has  concrete  pile  foundations.  The 
others  have  spread  footings  about  6  feet  below  grade. 

St.  Louis.  —  Present  practice  in  St.  Louis  schools  calls  for  High 
Schools  to  be  three  stories  and  full  basement  in  height,  all  other 
schools  to  be  two  or  three  stories  above  basement.  The  construc- 
tion is  fire-resisting  throughout,  including  brick  walls,  reinforced 
concrete  floors,  and  hollow-tile  partitions.  The  Humboldt 
School  includes  an  auditorium.  The  costs  given  include  heating 
and  ventilating,  plumbing  and  electric  work,  painting  and  deco- 
rating and  all  outside  grading  and  improvements.  Blackboards, 
desks,  shop  and  laboratory  equipment  and  portable  furniture 
are  not  included. 

Conclusions.  —  Municipal  responsibility  in  the  matter  of 
schoolhouse  "design  and  construction  cannot  be  evaded  on  the 
plea  of  economy.  Numerous  fires  in  school  buildings  have 
demonstrated  both  the  danger  to  life  and  the  short-sighted 
economy  of  combustible  construction,  while  present  differences 
in  cost  between  this  type  and  rightly  designed  fire-resisting  con- 
struction are  so  small  —  if,  indeed,  they  need  exist  at  all  —  that 
no  adequate  argument  can  be  advanced  to  justify  anything  but 
uniform  first-class  construction.  Safety  of  life  and  property,  less 
depreciation,  and  last,  but  not  least,  the  moral  responsibility  of 
a  municipality  to  enforce  right  methods  in  the  rnatter  of  building 
construction,  all  justify  a  reasonable  margin  of  added  expense  in 
securing  the  best  construction  possible.  But,  as  before  stated, 
it  is  questionable  whether  fire-resisting  construction  need  entail 
any  material  increase  in  cost  under  present  conditions.  Thus, 
in  response  to  short-sighted  clamors  for  economy,  the  Boston 
Board  of  Schoolhouse  Commissioners  has  been  endeavoring  to 
lower  the  cost  of  schoolhouses  by  changing  from  first-  to  second- 
class  construction,  but  the  author  is  advised  that  the  increased 
cost  of  lumber,  other  trade  conditions,  and  possibly  less  efficient 
planning  and  design,  have  all  operated  to  show  an  almost  negli- 
gible saving  over  previous  thoroughly  fire-resisting  buildings. 


CHAPTER  XXIV. 
RESIDENCES. 

Fire  Hazard.  - 

A  person  fears  fire  in  his  home  more  than  he  does  in  his 
office  for  two  reasons:  First,  because  all  he  holds  most  precious 
is  in  his  home.  A  fire  means  danger  to  his  family  and  homeless- 
ness  until  a  new  place  can  be  found.  Second,  his  responsibility 
for  the  safety  of  his  home  is  undivided.  He  alone  is  responsible 
for  the  preservation  of  his  home.  He  cannot  feel  that  someone 
else  should  take  care  of  these  things.  The  home  is  the  unit  of 
social  life;  its  destruction  has  a  more  far-reaching  influence  than 
the  mere  loss  of  furniture,  etc.  A  man  really  owes  it  to  society, 
as  well  as  to  his  family,  to  see  that  no  precautions  are  omitted  in 
the,  protection  of  his  home  against  fire.* 

Holocausts  such  as  an  Iroquois  Theatre,  a  Collinwood  School, 
or  a  Triangle  shirt-waist  factory  shock  the  world  by  their  fearful 
toll  of  human  lives,  but  were  the  true  record  known  of  all  lives 
lost  by  fire  year  after  year,  it  is  probable  that  residence  fires  would 
contribute  the  greatest  percentage  of  fatalities.  Nor  would  this 
be  in  remote  or  suburban  homes  alone,  where,  either  from  inac- 
cessible location  or  from  inadequate  fire  department,  quick  or 
efficient  means  of  protection  are  lacking.  The  fire  record  of 
every  large  city  will  show  that  many  lives  are  lost  in  dwelling 
houses,  and  sometimes  even  very  near  fire  department  houses  of 
the  highest  efficiency.  Witness  the  fire  in  the  Andrews  residence, 
in  New  York  City,  April  7,  1899,  wherein  twelve  lives  were  lost 
although  the  house,  at  Fifth  Avenue  and  67th  St.,  was  on  the 
same  cross  street  as  Fire  Department  Headquarters. 

The  principal  reasons  for  the  great  annual  loss  of  life  and 
property  in  residences  are  twofold : 

First,  carelessness,  in  regard  to  ordinary  causes  of  fires.  In 
Chapter  II,  in  a  discussion  of  the  usual  causes  of  fires,  it  was 
pointed  out  that  a  large  proportion  of  fires  may  be  classed  as 
"easily  preventable,"  and  in  no  class  of  buildings  is  this  more 
true  than  in  residences. 

*  From  pamphlet  entitled  "The  Prevention  of  Fire,"  issued  by  the  Rochester 
Chamber  of  Commerce. 

757 


758 


FIRE   PREVENTION   AND   FIRE   PROTECTION 


Second,  carelessness  exhibited  in  ordinary  construction.  The 
manner  in  which  the  usual  residence  contributes,  through  poor 
construction,  to  severe  fire  damage,  if  not  complete  loss,  is  thus 
described  by  Mr.  Francis  C.  Moore: 

Under  present  methods  a  frame  dwelling,  or,  for  that  mat- 
ter, a  brick  dwelling  of  ordinary  construction,  once  on  fire,  is 
seldom  saved.  With  defective  floors,  hollow  partitions,  open 
staircases,  and  hollow  spaces  in  side- walls  from  cellar  to  roof, 
affording  drafts  and  flues  for  carrying  flames,  modern  dwelling- 
houses  are  actually  constructed  on  the  principle  of  lungs  for 
breathing  flame.  Even  if  the  outer  walls  are  of  brick  or  stone 
they  do  not  retard  combustion,  since  the  conditions  for  it  are 
simply  those  of  an  ordinary  stove,  whose  contents  are  not  more 
judiciously  arranged  to  insure  rapid  combustion  than  are  such 
interiors.  It  rarely  happens  that  a  fire  starting  at  night  in  the 
cellar  or  in  the  lower  story  of  a  dwelling  is  extinguished  short  of 
loss  of  life  and  property.  This  ought  not  to  be  the  case,  as  it  is 
due  to  criminal  indifference  to  precautions  which  are  compara- 
tively inexpensive  and  which  ought  naturally  to  occur  to  any 
intelligent  mind.* 

It  will,  therefore,  be  profitable,  before  considering  fire-resisting 
residences,  to  investigate  the  common  causes  of  fires  in  combus- 
tible dwellings,  and  to  consider  the  remedies  therefor. 

Causes  of  Residence  Fires.  —  The  causes  of  fires  in  dwell- 
ings are  usually  more  easily  determined  than  in  other  buildings. 
A  classification  by  the  Home  Insurance  Company  of  3,298  fires 
in  residences,  of  which  the  causes  were  known,  showed  the  follow- 
ing result :  f 


Flues. 

Lightning. 

Incendiary. 

Electric 
lighting. 

Other  causes. 

1203 

272 

435 

116 

1272 

Disregarding  incendiary  fires  and  lightning  (concerning  which 
see  Chapter  XXVIII),  it  appears  that  defective  chimneys  or 
flues  were  responsible  for  36  per  cent,  of  the  total  number  of  fires, 
and  electric  lighting  about  3J  per  cent.  Of  the  remaining 
"other  causes,"  such  actions  of  personal  carelessness  as  have 

*  From  "How  to  Build  a  Home,"  by  Francis  C.  Moore,  formerly  President 
Continental  Insurance  Company. 

t  See  Chas.  E.  Eldridge  in  National  Fire  Protection  Association's  "Quar- 
terly," January,  1911. 


RESIDENCES  759 

previously  been  enumerated  in  Chapter  II,  and  carelessness  in 
constructive  features  other  than  flues  would  doubtless  account 
for  a  large  proportion  of  the  unmentioned  causes. 
Fire  Safeguards  Applicable  to  Ordinary  Construction.  — 

Much  may  be  done  through  comparatively  simple  safeguards  to 
improve  the  dangers  of  combustible  dwellings,  —  such  as  flues  or 
the  other  defective  featrnWenumerated  by  Mr.  Moore,  —  whether 
those  built  before  fire  protection  was  understood  and  practised, 
or  those,  which,  from  considerations  of  economy,  are  newly  built 
of  ordinary  frame  construction.  Such  safeguards  will  be  briefly 
considered,  principally  from  the  standpoint  of  combustible 
dwellings,  although  many  of  the  cautions  enumerated  will  be 
equally  applicable  to  fire-resisting  residences,  as  discussed  later. 
Chimneys  and  Flues.  — 

A   FABLE. 
BY  FRANKLIN  H.  WENTWORTH. 

F  Last  Summer  a  Good  Citizen  of  a  certain  town  not  over 
a  hundred  miles  from  almost  Everywhere,  built  a  Wooden 
house  for  a  Woman  and  her  Children.  He  built  the 
Chimney  of  Brick  because  he  had  to.  The  Chimney  was 
able  to  Stand  Alone,  so  he  did  not  have  to  prop  it  with 
Wood.  But  the  Floors  of  the  house  would  not  Stay  Up 
without  props.  The  Good  Citizen  saved  a  dollar  by  using 
the  Chimney  as  a  support  to  the  floors.  He  nestled  the 
ends  of  the  Floor  Joists  nicely  in  the  brick  of  the  Chimney. 
He  covered  up  the  job  and  got  his  money. 

The  Rains  fell  and  the  Winds  blew  in  the  most  Biblical 
manner,  and  Winter  came  after  its  fashion.  The  Chim- 
ney Settled  a  little;  and  there  was  a  tiny  Crack. 

One  morning  the  Woman  woke  up  with  Fire  all  About 
her.  She  tried  to  get  to  her  Children.  If  she  got  to  them 
no  one  Ever  Knew  it.  The  Good  Citizen  who  built  the 
house  was  Not  Arrested  for  Manslaughter.  He  is  build- 
ing Other  houses  of  the  Same  Kind  for  Other  women  and 
children. 

He  is  making  his  Living  by  it. 

Unfortunately,  such  a  case  as  is  depicted  by  Mr.  Wentworth  in 
the  above  fable  is  by  no  means  rare.  More  frequently  the  con- 
struction is  as  shown  in  Fig.  318,  where  both  studs  and  trimmers 
are  placed  tight  against  the  4-in.  fireplace  backing  and  flue 
coverings.  This  may  prove  safe  for  years,  but  a  "dry"  joint  in 
the  brickwork  or  a  crack  caused  by  settlement,  or  even  the  con- 
tinued transmission  of  heat  through  the  thin  masonry,  may  start 


760         FIRE    PREVENTION    AND    FIRE    PROTECTION 

^ Wood  Studs  - 


_  Trimmers  _ 
FIG.  318.  —  Faulty  Chimney  Construction. 


FIG.  319.  —  Elevation  of  Properly  Designed  Chimney. 

a  fire  at  any  moment.     Such  a  result  would  be  particularly  liable 
to  follow  a  chimney  fire  caused  by  the  collection  of  soot.     This 


RESIDENCES 


761 


is  one  reason  why  the  London  householder  is  fined  if  a  chimney 
fire  occurs  on  his  premises. 

A  properly  designed  chimney  is  shown  in  elevation  and  plan 
in  Figs.  319*  and  320  respectively. 


[f 

T 

a 

a 

•c     I 

a 

"^ 

?        ? 

•^ 

H 

o        o 

fH 

Header                             ^ 

v>           ;    '-/^  ":••'"" 

Fire  Place 


Hearth 

Arch  of  Brick,  Stone, 
Terra-cotta  or  Concrete. 


Header 


FIG.  320.  —  Plan  of  Properly  Designed  Chimney. 

Chimneys  should  be  built  from  the  ground  up  —  never  sup- 
ported upon  wood  floors  or  beams.     They  should  extend  at  least 


A  B 

FIG.  321.  —  Improper  and  Proper  Method  of  Drawing  Flues  together  at  Roof. 

3  ft.  above  flat  roofs,  and  at  least  2  ft.  above  the  highest  point  of 
a  peaked  roof.     Where  flues  are  drawn  together  at  the  roof  level, 

*  From  "How  to  Build  a  Home,"  by  Francis  C.  Moore,  formerly  President 
Continental  Insurance  Company. 


762         FIRE    PREVENTION    AND    FIRE    PROTECTION 

this  is  commonly  done  as  is  shown  in  Fig.  321A.  The  method 
shown  in  Fig.  321B  is  far  preferable,  as  regards  both  fire  protec- 
tion and  appearance. 

For  all  ordinary  chimneys,  8  ins.  of  brickwork  should  be  a 
minimum.  The  cost  will  be  very  little  more  than  for  a  4-in. 
thickness,  which  not  only  results  in  poor  fire  protection  but  in  a 
cold  flue  and  bad  draft. 

Before  deciding  upon  a  'half-brick'  (i.e.,  4-in.)  chimney, 
ask  your  architect  how  much  additional  it  would  cost  you  to 
build  an  8-in.  chimney.  You  will  probably  not  only  build  an 
8-in.  chimney,  but  you  will  line  it  with  burnt-clay  pipe.  If, 
after  learning  the  extra  expense,  you  are  willing  to  risk  your  life 
for  the  difference,  and  do  not  regard  the  safety  of  your  family, 
read  what  kind  of  man  St.  Paul  says  is  ;  worse  than  an  infidel.'  * 

In  addition  to  8  ins.  of  brickwork,  all  flues  should  be  lined 
continuously  from  the  bottom  of  flue,  or  from  the  throat  of  fireplace 
to  the  top  of  flue,  with  vitrified  clay  flue  lining  or  with  terra- 
cotta pipe.  Such  linings  must  be  placed  as  the  chimneys  are 
run  up,  and  care  should  be  taken  to  insure  good  butt  joints,  well 
set  with  cement  mortar.  As  a  general  rule,  round  flues  draw 
better  than  square  flues,  hence  for  ordinary  use  nothing  better 
can  be  employed  than  10-in.  diam.  terra-cotta  pipe,  the  sections 
of  which  fit  accurately  together  with  collar- joints,  the  same  as 
drain-pipe. 

If  flue  linings  are  not  used,  special  care  is  necessary  to  provide 
good  mortar,  and  plenty  of  it,  so  that  all  joints  in  the  brickwork 
will  be  well  filled  and  pointed. 

If  grates  are  to  be  set  in  fireplaces,  a  lining  of  firebrick  at  least 
2  ins.  thick  should  be  added  to  the  fireback,  unless  this  is  made 
of  soap-stone,  tile  or  cast-iron.  The  withes  or  brickwork  be- 
tween lined  flues  may  be  4  ins.  thick. 

Wood  studs  or  " headers"  should  never  be  placed  less  than 
2  ins.  away  from  the  brickwork  of  chimneys  or  flues.  Hearths 
should  be  framed  for  as  shown  in  Fig.  320,  which  gives  the  mini- 
mum requirements  of  the  National  Board  of  Fire  Underwriters' 
Building  Code;  while  the  trimmer  arch,  supporting  the  hearth, 
should  be  made  of  brick,  stone,  terra-cotta  or  concrete,  as  shown 
in  Fig.  319.  The  arch  should  butt  against  a  wooden  wedge  or 
skewback,  which,  in  turn,  should  be  supported  by  a  cleat  spiked 

*  From  "How  to  Build,  a  Home,"  by  Francis  C.  Moore,  formerly  President 
Continental  Insurance  Company. 


RESIDENCES  763 

to  the  header.  If  made  without  this  wedge  and  cleat,  subsequent 
shrinkage  would  be  apt  to  allow  the  fall  or  settlement  of  the  arch. 
The  practice  of  supporting  hearths  directly  on  wood  joists  or  on 
plank  laid  in  place  of  a  masonry  arch  has  resulted  in  many  fires. 

Heating  Apparatus.— 

Stoves,  Furnaces,  etc.,  should  be  placed  so  that  no  portions 
thereof  are  nearer  to  woodwork  than  2  feet.  Ceilings  over 
furnaces  should  be  of  wire  lath  and  plaster  or  other  incombus- 
tible construction,  in  lieu  of  which  a  suspended  fire-resisting 
shield  may  be  used  overhead.  To  prevent  possible  overheating 
in  a  furnace  the  principal  register  should  be  fixed  so  that  it 
cannot  be  closed;  also  floor  registers  should  never  be  placed 
directly  over  the  furnace. 

Stove-  and  Hot-air-Pipes.  —  The  primary  thought  in  the  in- 
stallation of  stove-  or  furnace-pipes  must  be  the  insulation  of 
all  woodwork  endangered  thereby.  This  may  be  accomplished 
either  by  keeping  such  pipes  a  sufficient  distance  away  from  wood- 
work, or  by  using  double  pipes  with  an  air-space  between,  or  by 
covering  the  pipes  with  an  insulating  covering  such  as  metal  lath 
and  plaster  or  asbestos.  Metal  lath  is  far  better  and  little  more 
expensive  for  use  in  front  of  furnace  pipes  in  stud  partitions. 

Steam  Pipes  should  not  be  placed  nearer  than  2  ins.  to  wood- 
work, unless  the  latter  is  protected.  If  used  in  stud  partitions, 
such  pipes  should  be  covered  with  sectional  asbestos  covering. 
Where  passing  through  floors,  metal  sleeves  and  cover  plates 
should  be  used.  For  details  of  floor-  and  partition-sleeves,  and 
data  concerning  the  hazards  of  steam  pipes,  see  article  "Fire 
Dangers  of  Steam  Pipes,"  in  the  National  Fire  Protection  Associa- 
tion's "Quarterly,"  January,  1911.  See  also  Chapter  XXVIII. 

Electric  Wiring  should  not  present  any  special  hazard  where 
present  approved  methods  of  installation  and  inspection  are 
followed.  -  Wiring  on  porcelain  insulators  is  often  used  when  an 
old  building  is  to  be  wired,  but  iron  conduits  with  metal  outlet 
and  junction  boxes  are  greatly  to  be  preferred.  The  principal 
dangers  from  electric  wiring  are  to  be  feared  in  those  more  remote 
localities  where  fire  underwriters'  regulations  are  not  followed. 

Fire  Stops.  —  Next  to  proper  chimneys,  and  flues,  the  most 
potent  safeguard  against  fire  hazard  in  residences  or  other  build- 
ings of  combustible  construction  lies  in  the  "fire-stopping"  of 
walls,  partitions  and  floors.  Fire  tends  to  spread  upward,  and 
hollow  walls  and  partitions,  hollow  spaces  back  of  furring  on  even 


764 


FIRE    PREVENTION    AND    FIRE    PROTECTION 


Furring 


masonry  walls  and  hollow  floors,  all  offer  runways  for  the  rapid 
communication  of  fire  from  cellar  to  attic  and  from  side  to  side. 
A  basement  fire  may  thus  spread  rapidly, 
out  of  sight,  until  the  flames  burst  from 
many  places  at  the  same  time. 

The  remedy  is  in  fire-stopping,  and,  if 
this  is  properly  done,  even  an  all-frame 
residence  may  be  made  considerably  safer 
against  the  spread  of  fire  than  brick  wall 
and  wood  floor  construction  without  fire 
stops. 

By  means  of  fire-resisting  stops  or  filling, 
all  continuous  spaces  which  would  otherwise 
act  as  chases  or  draught  flues  for  the 
spread  of  fire  vertically  or  laterally  are  cut 
off.  Thus  where  a  brick  wall  is  furred  and 


FIG.    322.  —  Fire-stop- 
ping and  Wall  Furring. 


plastered,  the  hollow  spaces  between  the  furring  strips  may  be 
cut  off  at  the  floor  line  by  setting  out  two  courses  of  brick  to 
the  full  thickness  of  the  furring,  both  above  and  below  the 
joists,  as  shown  in  Fig.  322. 

For  frame  houses,  methods  of  fire-stopping  outside  walls  with 
brick  are  shown  in  Fig.  323,  and  partitions  in  Fig.  324. 

For  outside  walls  a  still  better  plan,  although  more  expensive, 


FIG.  323.  —  Methods  of  Fire-stopping  Outside  Walls. 


RESIDENCES 


765 


is  to  fill  in  solid  between  all  studs  with  either  brick  or  hollow  tile 
blocks.     See  later  paragraph  "  Wood  and  Hollow  Tile." 


FIG.  324.  —  Methods  of  Fire-stopping  Partitions. 

Basement  Ceilings.  —  An  appreciable  element  of  fire-pro- 
tection will  be  added  to  a  frame  residence  if  all  basement  ceilings, 
but  especially  those  over  furnace  rooms,  dry-rooms,  laundries, 
etc.,  are  finished  with  metal  lath  and  plaster,  plaster  boards,  or 
asbestos  building  lumber.  A  still  more  efficient  construction  is 
made  by  filling  in  solid  between  the  first  story  joists  with  hollow 
tile  blocks  or  cinder  concrete,  or  mortar  or  mineral  wool  may  be 
filled  in  over  the  metal  lath  below. 

Stairs.  —  Basement  or  cellar  stairways  should  preferably  be 
surrounded  by  partitions  plastered  on  metal  lath,  or  covered  with 
plaster  board  or  asbestos  building  lumber.  A  standard  tin-clad 
door  for  the  opening  leading  to  cellar  is  also  desirable. 

For  upper  stories,  stairs  may  be  greatly  improved  as  to  safety 
and  retard  of  fire  if  the  spaces  between  stringers  and  between 
landing  joists,  etc.,  are  " pugged"  solid  with  mortar,  hollow  tile, 
or  other  fire-resisting  material  at  frequent  intervals. 

Closets.  —  Recesses  between  flues  and  corner  walls  are  often 
utilized  for  built-in  closets.  In  such  cases  the  flues  should  in- 
variably have  both  8-in.  masonry  walls  and  flue-lining.  Many 
fires  have  originated  from  fire  working  into  closets  through 
cracks,  caused  by  settlement,  etc,,  in  the  flue  walls. 


766        FIRE   PREVENTION   AND   FIRE   PROTECTION 

Shafts,  used  for  dumb-waiters,  lifts,  etc.,  form  vertical  chases 
of  considerable  hazard.  (See  Chapters  IX  and  XVI.)  They 
should  at  least  be  covered  on  the  inside  with  some  such  finish  as 
was  recommended  for  basement  ceilings,  while  doors  to  same 
should  preferably  be  tin-clad,  or  lined  with  tin  on  the  inside.  If 
extending  to  top  story,  they  should  be  vented  by  a  roof  sky- 
light. 

Roofs.  —  Notwithstanding  the  fact  that  the  shingle  roof  has 
been  called  "the  breeder  of  conflagrations,"  it  will  undoubtedly 
continue  the  most  popular  roof  covering  for  small  or  moderate 
sized  residences  for  years  to  come.  In  city  or  even  suburban 
limits,  the  conflagration  or  exposure  hazard  of  the  shingle  roof 
is  great,  as  has  been  pointed  out  in  connection  with  the  Chelsea 
fire.  Also,  sparks  from  chimney  fires  not  infrequently  ignite 
shingle  roofs.  For  these  reasons,  some  cities  have  already  pro- 
hibited shingle  roofs  within  the  fire  limits.  Fire-resisting  sub- 
stitutes for  wood  shingles  are  found  in  natural  slate,  vitrified 
roofing  tile,  and  asbestos  shingles,  as  described  in  Chapter  XXI. 

Fire-resisting  Residences.  —  To  those  familiar  with  build- 
ing operations  in  the  United  States,  it  would  seem  evident  that  a 
transition  in  our  domestic  architecture  is  now  taking  place  — 
a  transition  from  the  heretofore  almost  universal  combustible 
dwelling,  to  constructions  seeking  to  express  at  least  some  of  the 
elements  of  fire-resistance.  At  no  previous  period  has  so  much 
attention  been  directed  to  improvements  in  residence  design  and 
construction,  and  while  it  cannot  be  claimed  that  fire  protection  is 
entirely  responsible  for  all  improved  methods  at  present  popular, 
still  it  is  indisputably  true  that  the  evolution  of  fire-resisting 
buildings  of  other  types,  and  the  increased  production  and  uses  of 
fire-resisting  materials,  have  all  been  contributing  causes  to  the 
effort  to  express  permanence,  if  not  fire-resistance,  in  dwellings. 
There  is  also  a  growing  class  of  those  who  rightly  appreciate  the 
benefits  accruing  from  fire-resisting  construction  in  dwellings  — 
those  who  balance  such  items  as  decreased  insurance,  repair  and 
depreciation,  lessened  coal  bills,  and  freedom  from  vermin,  etc., 
with  the  often  deceptive  first  cost.  Even  a  casual  perusal  of 
present-day  architectural  journals  will  show  what  a  prominent 
place  the  fire-resisting  residence  is  gradually  assuming  in  domes- 
tic architecture  —  not  only  as  applied  to  large  and  expensive 
dwellings,  but  to  small  and  low-cost  houses  as  well.  It  will, 
therefore,  be  the  object  of  succeeding  paragraphs  to  illustrate 


RESIDENCES  767 

and  compare  the  more  practicable  methods  of  construction  which 
possess  qualities  of  fire-resistance.  These  constructions  vary 
from  what  is  really  "sham"  or  false  pretence  to  wholly  efficient 
fire  protection,  the  degree  of  efficiency  usually  varying  about  as 
the  cost.  A  rough  classification  of  such  constructions  will  in- 
clude (a)  Stucco  or  Plaster  houses,  (b)  Hollow  tile,  (c)  Concrete, 
(d)  Brick  or  stone,  and  (e)  Combinations  of  these. 

Stucco  Residences.  —  By  stucco  or  plaster  residences  is  here 
meant  those  constructions  in  which  an  outside  plaster  finish  is 
used,  whether  for  appearance  only,  or  from  some  consideration  of 
fire-protection,  over  walls  other  than  thoroughly  fire-resisting. 
Such  constructions  include  metal  lath  and  plaster  over  wood 
•  studs,  stucco  over  wood  studs  filled  between  with  hollow  tile, 
and  metal  lath  and  plaster  over  "metal  lumber." 

Metal  Lath  and  Plaster  over  Wood.  —  The  popularity  of 
the  many  wood-frame  stuccoed  houses  of  the  present  day  is  not 
due  to  any  consideration  of  fire-protection,  but  to  the  fact  that 
they  are  attractive  in  appearance,  not  much  more  expensive  than 
wood,  and,  generally,  cheaper  to  maintain.  Such  constructions 
do,  however,  possess  a  certain  degree  of  resistance  against  ex- 
posure fires,  and,  if  properly  fire-stopped  and  combined  with 
interior  metal  lath  and  plaster,  an  added  degree  of  resistance 
against  interior  fire  of  moderate  intensity. 

The  metal  lath,  whether  wire  or  expanded  metal,  should  pref- 
erably be  galvanized.  See,  also,  later  paragraph  "Concrete  and 
Stucco  Finishes." 

A  stucco  of  superior  weather  and  fire-resisting  qualities,  made 
largely  of  asbestic  or  ground  asbestos,  is  the  "  Asbestos  Stucco " 
manufactured  by  the  H.  W.  Johns-Manville  Co.  A  scratch  coat 
at  least  one-half  inch  thick  is  first  applied,  over  which  is  put  a 
one-quarter  inch  finishing  coat. 

Wood-  and  Hollow  Tile.  —  An  attempt  to  improve  the  fire- 
resistance  of  frame  buildings,  particularly  three-story  apartment 
houses  built  in  close  proximity  one  to  another  (within  city  limits, 
but  outside  the  restricted  frame  building  area),  led  to  an  experi- 
mental fire-test  (Boston,  Mass.,  1911)  to  determine  the  compara- 
tive fire-resisting  qualities  of  wood  studs  filled  in  between  with 
hollow  tile  blocks  and  covered  with  clapboards,  and  ordinary  wood 
stud  and  clapboard  construction.  A  cord-wood  fire  attaining  a 
temperature  of  800°  to  1000°  F.  was  maintained  for  about  1| 
hours  against  the  clapboard  side  of  the  wall,  with  the  result  that 


768         FIRE    PREVENTION    AND    FIRE    PROTECTION 

while  the  ordinary  construction  was  finally  completely  consumed, 
the  tile-filled  portion  remained  in  very  fair  condition.  The  studs 
were,  of  course,  consumed  to  a  slight  depth,  and  charred  to  a 
further  depth,  but  the  reverse  side  of  the  wall,  which  was  plas- 
tered, was  apparently  in  perfect  condition,  and  at  no  time  was 
the  temperature  of  the  plaster  such  as  to  prevent  the  hand  being 
held  firmly  in  place. 

While  the  result  was  most  creditable  for  a  blank  wall,  the 
construction  does  not,  in  the  author's  opinion,  deserve  serious 
consideration.  Tile-filled  walls  would  be  of  little  avail  without 
tile-filled  floors,  and  even  so,  the  result  would  be  a  makeshift  at 
a  cost  closely  approximating  the  far  better  hollow  tile  construc- 
tion. 

Metal  Lumber*  consists  of  I- joists  ,  channel  joists  and 

studs    I    ,  corner  joists I    ,  wall  ribbons    >    ,  and  crowning 

members  i j,  made  of  sheet  steel,  No.  14  to  18  gauge,  in 

lengths  up  to  10  feet,  above  which  splicing  is  necessary.  These 
metal  shapes  are  used  as  substitutes  for  ordinary  wood  framing, 
in  the  construction  of  walls,  floors,  roofs,  partitions,  etc.,  in 
residences  or  other  buildings  of  a  similar  nature.  The  various 
forms  are  provided  with  prongs  on  the  flanges  for  the  attach- 
ment of  metal  lath.  These  are  shown  in  Fig.  98  which  illustrates 
a  metal  lumber  partition  stud. 

In  wall  and  partition  construction  the  studs  are  braced  by 
the  metal  lath  which  is  applied  outside  and  inside  to  receive  the 
stucco  finish  and  interior  plastering.  In  floor  construction,  the 
I-joists  are  braced  by  metal  bridging.  Crowning  members  are 
used  at  the  tops  of  all  partitions  as  fire  stops. 

A  typical  floor  construction  is  shown  in  Fig.  325.  For  long 
girders,  steel  beams  are  used  with  shelf-angles  to  receive  the 
I-joists,  which  are  spaced  16  ins.  to  18  ins.  centers.  These  are 
riveted  to  the  wall  ribbon.  For  the  ceiling,  metal  lath  is  at- 
tached to  the  joists  by  means  of  the  prongs.  For  the  floor  finish, 
metal  lath  is  usually  first  spread  over  the  joists,  upon  each  of 
which  2-in.  X  3-in.  wood  nailing  strips  are  laid  longitudinally 

*  Made  by  the  Berger  Manufacturing  Company,  Canton,  Ohio. 


RESIDENCES  769 

and  nailed  into  the  cracks.     Concrete  is  then  filled  in  between 
these  nailing  strips,  and  the  finished  wood  floor  is  applied. 


Ceiling 
Plaster 

FIG.  325.  —  "Metal  Lumber"  Floor  Construction. 

Metal  lumber  may  be  used  also  for  floor  and  partition  con- 
struction in  connection  with  exterior  masonry  walls.  However 
used,  the  material  is  usually  cut  to  length  at  the  factory,  care- 
fully marked  and  shipped  to  the  site  with  erection  diagrams. 
Splices  and  joints  are  riveted. 

Although  particularly  suited  to  residence  work,  this  substitute 
for  wood  construction  has  been  extensively  used  in  a  wide  variety 
of  structures.  While  far  from  being  fire-resisting  under  severe 
test,  the  great  reduction  of  combustible  material  resulting  from 
its  use  contributes  materially  to  safety  from  fire. 

Hollow-tile  Residences.  —  The  demand  for  plastered  ex- 
teriors, and  also  the  demand  for  something  better  than  the 
ordinary  combustible  residence,  have  led  the  manufacturers  of 
terra-cotta  tile  to  make  and  exploit  new  patterns  of  hollow  tile 
especially  suited  to  residence  work,  with  the  result  that  this  type 
of  construction  has  developed  rapidly  during  the  past  few  years 
from  an  experimental  to  a  well-recognized  type.  Many  details 
of  terra-cotta  constructions  which  have  been  discussed  in  previ- 
ous chapters  are  equally  applicable  to  residence  work,  but  some 
special  applications  of  the  material  are  worthy  of  mention. 


770         FIRE    PREVENTION    AND    FIRE    PROTECTION 

"Natco"  Hollow  Tile  Blocks,  manufactured  by  the  National 
Fire  Proofing  Company  especially  for  residence  work,  are  made 
of  hard-burned  material  in  the  following  standard  sizes:  3,  4, 
6,  8,  10  and  12  ins.  thick  by  12  ins.  wide  and  12  ins.  long.  Jamb 
blocks  for  use  at  window  reveals  and  half  jamb  blocks  (the  latter 
being  used  for  breaking  vertical  joints  in  successive  courses)  are 


JAMB  BLOCKS 


FIG.  326.  —  "Natco"  Jamb  and  Half  Jamb  Blocks. 


illustrated  in  Fig.  326.  "Half  blocks,"  that  is,  6  ins.  long,  may 
be  obtained  for  all  of  the  above  types,  in  order  to  make  up  any 
required  story  height,  etc. 

All  of  these  blocks  are  scored  with  deep  dovetail  grooves  on  all 
sides  in  order  to  provide  a  strong  mechanical  bond  for  both  the 
mortar  joints  and  the  exterior  or  interior  plastering. 

Walls  and  Partitions.  —  Footings  should  be  of  stone  or  pref- 
erably concrete,  on  which,  up  to  the  under  side  of  first  floor, 
should  be  placed  the  nine-hole  12  X  12  X  12-in.  blocks,  the  corner 
bonding  of  which  is  secured  by  using  6  X  12  X  12-in.  blocks  at 
the  corners,  with  width  alternating  in  direction,  as  shown  in 
Fig.  327.*  Where  below  the  surface  of  surrounding  ground, 
salt-glazed  or  vitrified  tile  may  be  advantageously  used. 

Walls  of  upper  stories  (and  even  basement  walls  in  small 
dwellings)  are  usually  made  of  8  X  12  X  12-in.  tile,  with  voids 
placed  vertically. 

*  The  illustrations  referring  to  hollow-tile  residence  construction  are  taken 
by  permission  from  catalog  of  the  National  Fire  Proofing  Company,  or  from 
"Building  Progress"  Magazine  published  by  the  same  company. 


RESIDENCES 


771 


Load-bearing  partitions  are  made  of  the  same  blocks  as  used 
for  exterior  walls.  To  develop  full  strength  the  blocks  should 
be  set  on  end. 


FIG.  327.  —  Hollow  Tile  Wall  Construction. 


The  ultimate  loads  per  lineal  foot  of  wall,  in  pounds,  for 
"Natco"  blocks  used  in  exterior  walls  or  load-bearing  partitions 
are  as  follows : 


Width 

Ultimate  load 

Width 

Ultimate  Load 

Size  of  tile. 

of  wall 
Itile 

per  lineal  foot 
of  wall  in 

of  wall 
2  tiles 

per  lineal  foot 
of  wall  in 

thick. 

pounds. 

kthick. 

pounds. 

4"X12"X12" 

4" 

114,201 

8" 

228,402 

6"X12"X12" 

6" 

142,862 

12" 

285,724 

8"  X  12"X12" 

8" 

202,131 

16" 

404,262 

10"  X  12"  X  12" 

10" 

228,226 

20" 

456,452 

12"  X  12"  X  12" 

12" 

259,300 

24" 

518,600 

Sub-dividing  partitions,  carrying  their  own  weight  only,  may 
be  built  of  blocks  laid  on  side.  Such  partitions  should  be  built 
on  the  floor  arches,  and  be  wedged  under  the  arches  above.  A 


772         FIRE    PREVENTION    AND    FIRE    PROTECTION 

sufficient  number  of  full  porous  blocks  should  be  used  for  nailing 
purposes. 

Fireplaces  and  Flues  for  hollow  tile  walls   are   shown  for  a 
typical  case  in  Fig.  328. 

f^ 

Terra  Cotta  Flue  Lining 

Firebrick  Lining' 


Cemeni 
Plaster 


FIG.  328.  —  Hollow  Tile  Fireplace  and  Flue  Construction. 


Floors  are  generally  made  of  the  combination  terra-cotta  and 
concrete  type  described  in  Chapter  XIX,  or  of  the  "Johnson" 
type,  as  described  in  Chapter  XVII.  Safe  loads  for  both  of  these 
floors  are  given  in  the  chapters  mentioned.  A  brief  specification 
for  the  combination  floor  system  is  as  follows : 

General.  —  Floor  construction  will  be  of  the  type  known  as 
the  Combination  Hollow  Tile  and  concrete  floor  arch  construc- 
tion, consisting  generally  of  4 -inch  reinforced  concrete  beams 
spaced  16  inches  on  centers  with  Hollow  Tile  Blocks  between, 
all  to  have  at  least  4  inches  bearing  on  walls. 

Concrete.  —  All  concrete  used  in  floor  arches  will  consist  of 
one  part  Portland  cement,  two  parts  clean  sharp  sand,  and  four 
parts  broken  stone  or  gravel  of  such  size  as  will  pass  through  a 
three-quarter  inch  ring.  Concrete  will  be  of  wet  mixture  and 
must  be  well  tamped  and  worked  around  reinforcing  steel  after 
pouring. 

Reinforced  Steel.  —  Steel  rods  for  floor  construction  must  be 
of  such  type  as  will  offer  a  mechanical  bond  with  the  concrete. 


RESIDENCES 


773 


Corrugated,  twisted  or  similar  type  will  be  acceptable.  Steel 
must  have  an  elastic  limit  of  not  less  than  one-half  the  tensile 
strength.  Rods  must  be  clean  and  free  from  rust  scales  before 
placing  in  position  and  must  be  placed  not  over  1  inch  above 
bottom  of  floor. 

Tile.  —  Depth  of  tile  filler  blocks  will  be  regulated  by  span 
and  load  to  be  carried  and  will  be  of  size  indicated  on  the  plans. 
All  blocks  will  be  wet  before  concrete  is  placed  so  as  to  insure  a 
good  bond  with  the  concrete. 

Centers.  —  Centers  must  be  of  such  size  as  to  insure  their 
not  deflecting  under  the  weight  of  the  wet  concrete,  and  must 
be  provided  in  such  quantity  as  to  insure  speedy  work.  Care 
must  be  taken  not  to  remove  the  centers  before  the  concrete  is 
hard,  and  under  long  spans  a  center  line  of  supports  must  be 
maintained  for  at  least  three  weeks  after  the  concrete  has  been 
poured.  In  cold  weather  the  centers  must  be  left  in  place  until 
directed  by  the  architect  to  remove  them. 


Facing  Tile 


Tile  Slab 


Concrete  Slab  over  tile  when 

necessary  to  increase  the 

strength  of  arch 


Hollow  Tile 


i^Rein forced  Concrete  Beams 
16  on  centers 


Rod  Reinforcement 

Twisted  or  Corrugated 


Hollow  Tile  Wall 


FIG.  329.  —  Hollow  Tile  Wall  and  "Combination"  Floor 
Construction. 


A  general  detail  of  wall  and  " combination"  floor  construction 
is  shown  in  Fig.  329.  The  walls  are  built  up  to  within  an  inch 
or  two  of  the  under  side  of  floor  arches.  Solid  tile  slabs  are  then 
laid,  horizontally  (6  ins.  wide  for  an  8-in.  wall),  to  make  a  bed  or 
ledge  for  the  support  of  the  floor  arches,  to  close  up  the  voids  in 


774 


FIRE    PREVENTION   AND    FIRE    PROTECTION 


the  ends  of  the  wall  blocks,  and  to  act  as  fillers  or  levelers  to 
bring  the  floors  at  proper  heights.  These  slabs  should  always 
be  of  solid  material.  At  the  floor  thickness  the  wall  is  faced  with 
2-in.  facing  tile.  The  walls  for  the  next  story  are  then  started  on 
top  of  the  floor  arches. 

The  application  of  the  Johnson  system  to  residence  work  is 
shown  in  Fig.  330.     In  this  case  a  1-in.  facing  slab  is  used. 


FIG.    330.  —  "Johnson"  Floor  as  used  in  Residences. 


Columns  of  terra-cotta  tile  may  be  made  of  the  " Monarch" 
type,  as  described  on  page  378,  or  of  the  combination  terra-cotta 
and  reinforced  concrete  type,  as  described  on  page  379.  Girders 
between  columns  may  be  made  of  reinforced  concrete. 

Window  Openings.  —  Jamb  rebates  for  the  weight  boxes  of 
window  frames  are  made  by  using  the  special  jamb  blocks  shown 
in  Fig.  326.  Vertical  joints  at  jambs  are  broken  by  using  half 
jamb  blocks  in  alternate  courses.  The  space  between  the  blocks 
and  frame  box  should  be  well  filled  with  mortar  to  prevent  the 
passage  of  air  or  moisture. 

Window  heads  may  be  made  of  jamb  blocks,  cut  with  radial 


RESIDENCES 


775 


joints  so  as  to  form  a  flat  arch,  or  a  better  detail  is  to  use  regular 
wall  blocks  filled  with  concrete  and  reinforcing  rods. 

Sills  are  made  of  4-in.  blocks  laid  on  side,  either  level  (in  which 
case  the  slope  of  sill  is  made  in  the  cement  finish)  or  on  a  slight 
angle  to  follow  line  of  finished  sill. 

Window  jamb,  lintel  and  sill  sections  as  used  in  a  residence  at 
Orange,  N.  J.,  —  Dillon,  McClellan  &  Beadel,  Architects,  —  are 
shown  in  Fig.  331. 


WINDOW 

JAMB  AND  SILL  ^^JT"  ^XlX^~~  WINDOW  LINTEL 

FIG.  331.  —  Hollow  Tile  Window  Jamb.  Lintel  and  Sill  Construction. 


Roofs.  —  Pitched  roofs,  as  used  in  the  great  majority  of  resi- 
dences, are  both  difficult  and  expensive  to  build  of  hollow-tile 
construction.  If  the  lines  are  simple,  as  with  a  double  pitched 
roof  from- a  central  ridge,  with  gable  walls  at  each  end,  the  roof 
slab  construction  may  be  made  of  combination  terra-cotta  and 
reinforced  concrete,  exactly  like  the  floors.  The  roof  arches  then 
bear  on  the  gable  walls  and  on  cross  partitions  built  up  from  the 
floor  below.  When,  however,  numerous  hips  and  valleys  are 
introduced,  the  construction  becomes  much  more  complicated, 
as  structural  steel  supports  are  necessary,  and  these  add  greatly 
to  the  expense  and  difficulty  of  the  work. 

For  these  reasons,  wood  roofs  are  generally  used  on  hollow-tile 
residences.  The  roof  plate  may  be-  secured  by  means  of  plate 


776 


FIRE    PREVENTION    AND    FIRE    PROTECTION 


bolts  set  in  concrete  filling  in  the  voids  of  wall  blocks,  as  shown 
in  Fig.  332. 


Attic  Floor  Joists 
spiked  to  rafters 


Bolt  for  fastening  Roof  Plate 
'imbedded  in  cement  mortar 


FIG.  332.  —  Wood  Roof  Construction  on  Hollow  Tile  Walls. 


Concrete  Residences.  —  Concrete  is  used  for  residence  work 
in  three  distinct  forms,  viz.,  —  as  finished  hollow  blocks,  in 
imitation  of  stone,  —  as  hollow  tile,  for  the  reception  of  a  surface 
coating  of  plaster  or  stucco,  —  and  as  reinforced  or  monolithic 
construction. 

Concrete  blocks,  also  termed  " mortar-blocks"  and  "concrete 
building  tile,"  have  been  described  as  regards  manufacture,  fire- 
resisting  properties,  etc.,  in  Chapter  VII;  also  as  to  their  general 
use  in  wall  construction  in  Chapter  XX. 

Concrete  Blocks.  —  Exterior  walls  for  residences,  made  of  con- 
crete blocks,  while  satisfactory  enough  from  a  fire-resisting  stand- 
point for  the  use  intended,  are  generally  far  from  artistic  in 
appearance.  The  duplication  by  the  hundreds  of  blocks  struck 
off  from  the  same  moulds,  made  to  resemble  rock-faced  stone,  etc., 
has  produced  such  an  artificial  appearance  that  the  industry  of 


RESIDENCES  777 

finished  concrete  blocks  has  not  made  much  headway.  Some 
very  superior  and  even  artistic  work  of  this  nature  has  been  done, 
notably  by  Purdy  &  Henderson  in  several  buildings  in  Havana, 
Cuba,  where  even  very  elaborate  ornamental  features  have  been 
cast  in  concrete  in  sand  moulds;  but  when  done  well,  the  work  is 
expensive,  and  of  doubtful  superiority  over  other  simpler  methods. 

Concrete  Building  Tile  are  used  for  residence  work  in  practi- 
cally the  same  manner  as  the  terra-cotta  hollow  tile  previously 
described.  In  some  localities,  especially  in  New  York  City, 
Chicago,  Rochester,  N.  Y.,  and  Youngstown,  Ohio,  many  resi- 
dences have  been  constructed  with  walls  of  concrete  tile  — 
some  having  the  floors,  partitions,  etc.,  of  like  construction.  In 
Youngstown  a  block  of  62  workingmen's  houses  was  recently 
built  after  this  method. 

Shapes  and  sizes  of  blocks  vary  with  the  factories  making  these 
products.  Catalogs  and  further  information  may  be  had  by 
addressing  the  Chicago  Structural  Tile  Co.,  353  Dearborn  St., 
Chicago,  —  The  Concrete  Stone  and  Sand  Co.,  Youngstown, 
Ohio,  —  and  Whitmore,  Rauber  &  Vicinus,  Rochester,  N.  Y.,  etc. 

Fig.  333  illustrates  wall  construction.  The  end  voids  of  the 
corner  blocks  are  filled  with  concrete  to  add  stiffness  and  to 


Corner  Til 
FIG.  333.  —  Concrete  Building  Tile  Wall  Construction. 

increase  the  bond.  Lintel  construction  over  windows,  doors, 
etc.,  is  shown  in  Fig.  334,  wherein  the  concrete  tile  are  reinforced 
by  steel  rods  surrounded  with  concrete  which  is  poured  into  holes 
cut  at  the  joints  in  tops  of  blocks.  Rebated  jamb  blocks  for  the 
window  boxes  are  also  shown.  Fig.  335  illustrates  the  usual  fire- 
resisting  floor  construction,  made  of  reinforced  concrete  beams 
4  ins.  wide  between  concrete  tile  filler  blocks. 

The  permeability  of  concrete  blocks  and  concrete  tile  varies 


778         FIRE    PREVENTION    AND    FIRE    PROTECTION 


Concrete  introduced  through 
holes  cut  in  tile\ 


FIG.  334.  —  Concrete  Building  Tile  Lintel  Construction. 


greatly  with  the  mixture  and  method  of  making.  Compare 
Chapter  VIII,  page  288.  Hence  to  insure  an  impervious  wall, 
either  blocks  of  a  wet  mixture  with  fine  aggregates  and  rich  in 
cement  must  be  used,  or  some  system  employing  double  blocks 
with  a  continuous  air-space. 


Cinder  Concrete   Phlislied  Moor 


^"Plaster 
'Stucco 

FIG.  335.  —  Concrete  Building  Tile  Wall  and  Floor  Construction. 


Reinforced   Concrete,   as   applied   to   residence  work,   has   not 
shown  as  great  development  as  the  same  material  has  in  other 


RESIDENCES  779 

types  of  structures .  The  principal  reason  lies  in  the  excessive 
cost  of  the  wood  forms  required  for  the  many  small  subdivisions 
of  the  usual  plan  and  for  those  features  of  design  which  give  the 
house  its  individuality.  If  many  houses  could  be  built  from  one 
set  of  moulds,  as  in  the  Edison  plan  of  multi-poured  houses,  the 
cost  of  each  would  be  greatly  reduced;  but  it  is  difficult  to  be- 
come enthusiastic  over  such  a  proposed  repetition,  unless  for 
workingmen's  cottages  in  mill  towns,  etc.  In  large  and  expensive 
residences  the  cost  of  forms  assumes  much  less  importance. 

Nevertheless,  some  very  excellent  work  in  the  way  of  com- 
paratively small  and  inexpensive  dwellings  has  been  accom- 
plished.* 

Brick  and  Stone  Residences  do  not  need  any  particular 
comment  as  to  fire-resistance,  provided  the  scheme  of  fire-resist- 
ing construction  is  consistently  carried  out.  It  has  already  been 
pointed  out  that  with  proper  safeguards,  an  all-frame  residence 
may  be  made  far  safer  from  ravage  by  fire  than  a  brick-  or  stone- 
walled structure  with  wood-joist  floors  and  partitions,  etc., 
without  safeguards.  Incombustible  walls  do  not  constitute  any 
great  degree  of  fire-safety.  To  lay  any  claim  whatever  to  fire- 
resistance,  brick-  or  stone-walled  dwellings  should  have  fire- 
resisting  floors  and  partitions.  The  former  may  be  of  concrete, 
either  reinforced  monolithic  or  in  combination  with  terra-cotta 
tile  or  concrete  tile,  as  previously  described,  while  the  latter  may 
be  of  brick,  hollow  tile  or  reinforced  concrete. 

Combination  Constructions.  —  Combination  floor  con- 
structions consisting  of  concrete  beams  for  strength  and  terra- 
cotta or  concrete  tile  fillers  for  lightness  have  already  been 
described.  Similar  combinations  of  materials  have  been  found 
both  practical  and  economical  for  other  portions  of  residence 
work,  particularly  for  wall  construction,  where  one  material, 
used  for  its  decorative  or  load-carrying  properties,  is  supple- 
mented by  another  material  to  act  as  a  backing  or  insu- 
lator. Several  of  these  combination  wall  constructions  are  as 
follows : 

Brick  and  Hollow  Tile.  —  An  8-in.  hollow-tile  wall  with  brick 
facing  is  shown  in  Fig.  336.  To  tie  the  two  materials  together, 
every  tenth  course  of  brick,  as  at  A.  is  tied  over  the  tile  by  means 
of  full  headers,  the  remaining  4  ins.  being  filled  in  with  hollow 

*  See,  particularly,  "Reinforced  Concrete  for  the  Small  House,"  by  C.  R. 
Knapp,  in  "1910  Proceedings  of  the  National  Association  of  Cement  Users." 


780 


FIRE    PREVENTION    AND    FIRE    PROTECTION 


brick  as  shown.     All  other  courses  have  bats  or  half  headers 
butting  up  against  the  hollow  tile. 


Courses   "A  A^'  have 
full  headers.  Other 
courses  have  half  headers 


FIG.  336.  —  Construction  of  Hollow  Tile  Wall  with  Brick  Facing. 

Combination  brick  and  concrete  tile  may  be  used  in  much  the 
same  way. 

Stone  and  Hollow  Tile. — Solid  stone  walls  are  apt  to  be  damp 
unless  interior  furring  is  provided.  A  good  fire-resisting  furring 
for  exterior  stone  walls  is  shown  in  Fig.  337. 

Hollow  Tile  and  Concrete.  —  The  patented  " Ribbed  Concrete" 
type  of  wall  made  by  the  New  York  Holding  and  Construction 
Co.,  is  illustrated  in  Fig.  338.  This  construction  consists  of 


RESIDENCES 


781 


FIG.  337.  —  Stone  Wall  Construction  with  Hollow  Tile  Furring. 

salt-glazed  hard-burned  terra-cotta  blocks,  strengthened  at  the 
joints  by  means  of  reinforced  concrete  filling.  All  blocks  are 
uniformly  18  ins.  long,  with  thicknesses  and  heights  as  follows: 


Width  of  block. 

Finished  width  of  wall. 

Heights  of  blocks. 

1\  ins. 
10£  ins. 
12f  ins. 

9J  ins. 
12£  ins. 
14f  ins. 

12,  16  and  18  ins. 
12  and  16  ins. 
9,  12  and  14  ins. 

Plaster- 


FIG.  338.  —  "Ribbed  Concrete"  Wall. 


The  blocks  are  laid  without  breaking  joint,  so  that  the  E- 
shaped  ends,  when  butted  together,  form  dovetailed  voids  into 
which  metal  reinforcement  and  concrete  grout  are  placed  story 
by  story,  thus  giving  vertical  concrete  columns  in  every  fourth 


782 


FIRE    PREVENTION    AND    FIRE    PROTECTION 


void,  or  at  every  joint.  The  blocks  are  scored  on  both  sides  for 
the  receipt  of  exterior  stucco  and  interior  plaster. 

This  method  of  construction  results  in  a  stiff  and  strong  wall, 
well  suited  to  residences  and  other  types  of  suburban  buildings, 
for  which  it  has  had  a  somewhat  extended  use. 

Concrete  and  Stucco  Finishes.  —  While  not  particularly 
pertinent  to  the  subject  of  fire-resistance,  the  question  of  wall 
construction  for  residences  would  not  be  complete  without  some 
reference  to  exterior  and  interior  finishes. 

Concrete  Finishes.  —  The  treatment  of  the  surfaces  of  concrete 
which  is  poured  or  tamped  in  forms  is  'too  large  a  subject  to 
be  discussed  here.  The  walls  may  be  left  as  they  come  from 
the  forms,  showing  the  board  marks,  —  or  they  may  be  treated 
when  green  with  a  stiff  scrubbing  brush,  —  or,  when  set,  with 
wire  brushes  or  carborundum  stone,  —  according  to  the  finish 
desired.  For  more  detailed  information  on  this  subject,  refer- 
ence may  be  made  to  the  Proceedings  of  the  National  Association 
of  Cement  Users,  particularly  "  Exposed  Selected  Aggregates  in 
Monolithic  Concrete  Construction,"  by  Albert  Moyer,  Vol.  IV, 
and  to  the  "  Report  of  Committee  on  Exterior  Treatment  of 
Concrete  Surfaces,"  L.  C.  Wason,  Chairman,  Vols.  VI  and  VII. 


FIG.  339.  —  Stucco  on  Hollow  Tile,      FIG.  340.  —  Stucco  on  Hollow  Tile, 
Sand  Finish.  Stippled  Sand  Finish. 

Stucco  on  Hollow  Tile.  —  Various  finishes  are  best  shown  by 
illustrations,  as  follows:* 

Fig.  339  shows  a  "sand  finish"  of  Portland  cement  and  sand. 

*  Courtesy  of  National  Fire  Proofing  Company. 


RESIDENCES 


783 


Fig.  340  shows  a  " stippled  sand  finish"  of  Portland  cement  and 
sand. 

Fig.  341  shows  a  "rough  cast"  of  Portland  cement,  sand  and 
stone  screenings. 


FIG.  341.  —  Stucco  on  Hollow  Tile,    FIG.  342.  —  Stucco  on  Hollow  Tile, 
Rough  Cast  Finish.  Pebble  Dash  Finish. 

Fig.  342  shows  a  "pebble  dash"  of  Portland  cement,  sand  and 
pebbles  applied. 

Specifications  for  the  above  finishes,  recommended  by  the 
National  Fire  Proofing  Co.,  are  as  follows: 

WETTING:  The  tile  should  be  well  wetted  before  applying 
the  mortar. 

MORTAR:  Mortar  to  be  composed  of  sharp  sand  and  a 
standard  Portland  cement. 

BROWN  COAT:  Sand  and  cement  to  be  mixed  in  propor- 
tions of  three  to  one  with  6  per  cent,  of  lime  putty.  Lime  to  be 
properly  slaked  and  screened  through  a  TVinch  mesh  sieve  and 
allowed  to  cool  and  then  be  mixed  with  water  before  mixing  with 
the  sand  and  cement.  Sand  and  cement  in  the  proper  propor- 
tions to  be  mixed  dry  before  mixing  with  the  putty.  All  to  be 
thoroughly  mixed  to  the  proper  consistency  before  applying  to 
the  wall.  All  walls  to  have  a  good  heavy  coat  of  the  foregoing 
composition  and  to  be  rodded  and  straightened  by  means  of  a 
straight  edge  and  darby  and  left  uniformly  plumb  and  straight. 

ROUGH  CAST  COAT:  After  the  brown  coat  has  thor- 
oughly set  apply  the  rough  cast  coat,  which  is  to  be  composed 
of  limestone  screenings,  sharp  sand  and  cement  in  the  following 
proportions:  two  of  limestone  screenings,  one  of  sand  and  one 
of  cement.  This  mixture  is  to  be  made  soft  enough  that  it  can 
be  thrown  on  the  wall  by  means  of  a  shingle  or  paddle.  Care 
must  be  taken  to  cover  the  entire  surface  with  an  even  coat  and 
left  so  that  there  will  be  no  unevenness  other  than  that  caused  by 


784         FIRE    PREVENTION    AND    FIRE    PROTECTION 

the  roughness  of  the  material.  Enough  of  this  mixture  should 
be  mixed  at  one  mixing  to  cover  an  entire  wall.  The  entire  wall 
must  be  rough-casted  at  one  time  so  that  there  will  be  no  joinings, 
streaks  or  discolorations  after  the  completion  of  the  work,  and 
must  be  left  in  an  even  and  uniform  color  in  a  first-class,  work- 
manlike manner.  If  the  weather  is  hot  it  will  be  necessary 
to  spray  the  finished  wall  twice  a  day  for  a  period  of  three  or  four 
days  after  the  completion  of  the  work. 

If  it  be  desired,  gravel  can  be  used  in  place  of  stone  screen- 
ings in  the  same  proportions. 

If  it  be  desired  to  leave  a  granule  surface,  use  sharp  sand  in 
the  proportion  of  three  of  sharp  sand  and  one  of  cement.  To  be 
properly  floated  twice  and  left  in  an  even  granuled  surface  free 
from  voids,  chip  cracks,  blisters  or  other  defects.  The  entire 
wall  should  be  floated  at  one  time  to  prevent  joinings  or  streaks. 
If  the  weather  is  hot  this  should  also  be  sprayed. 

Stucco  on  Metal  Lath.  —  For  outdoor  purposes,  it  is  best  to 
use  galvanized  metal  lath.  There  are  various  kinds,  woven, 
welded,  expanded,  any  one  of  which  can  be  used.  That  having 
a  large  cross-section  of  metal  and  being  heavily  coated  with  gal- 
vanizing material  is  likely  to  be  the  most  durable,  if  moisture 
should  penetrate  through  the  plastering  to  this  material.  It 
should  be  thoroughly  tied  to  furring  at  intervals  not  exceeding 
16  ins.  with  galvanized  wire.  The  furring  should  leave  sufficient 
space  for  the  mortar  to  push  through  the  mesh  and  clinch  without 
interference  from  the  backing  to  which  the  furring  is  attached.* 

Interior  Finish.  —  While  the  interior  finish  of  residences  is 
usually  plaster,  the  greatly  increased  use  of  hollow  tile  and 
concrete  for  walls,  etc.,  has  suggested  a  frank  unfinished  interior 
treatment  of  those  materials.  The  following  quotations  are 
given  principally  as  a  suggestion  as  to  what  may  be  accomplished 
along  these  lines. 

The  possibilities  of  the  interior  treatment  of  a  house  of 
terra-cotta,  provided  the  house  is  really  carried  out  in  a  fireproof 
construction,  are  also  very  considerable.  The  interior  use  of  the 
tile  construction,  including  the  tile-arch  construction,  though 
comparatively  recent,  is  much  older  in  this  country  than  that  of 
hollow  blocks  as  the  material  of  the  outer  walls.  Here,  also,  it 
was  a  sad  sight  to  see  a  construction,  evidently,  during  its  prog- 
ress, susceptible  of  an  interesting  and  expressive  treatment,  as, 
for  example,  a  stairway  with  its  soffits,  swathed  and  hid  in  an 
envelope  of  plaster,  which  deprived  it  of  all  interest  and  expres- 
sion. Few  householders,  it  is  true,  would  care  to  have  their  liv- 
ing rooms  lined  with  visible  blocks  of  terra-cotta.  But  there  are 
features  in  a  dwelling,  such,  for  instance,  as  a  staircase  and  a 

*  Report  of  Committee  on  Exterior  Treatment  of  Concrete  Surfaces,  "Pro- 
ceedings National  Association  of  Cement  Users,"  Vol  VI. 


RESIDENCES  785 

staircase  hall,  such  for  instance,  as  a  bathroom,  places  of  passage 
or  of  resort,  not  of  sojourn,  in  which  an  exposure  and  treatment 
of  the  actual  material  and  construction  would  be  appropriate 
and  welcome.  Whoever  doubts  this  may  be  invited  to  visit 
and  inspect  that  admirable  work,  the  chapel  of  Columbia  Uni- 
versity, and  see  to  what  interior  detail  the  material  readily  lends 
itself  in  the  hands  of  an  artist.* 

If  the  " combination"  floor  of  reinforced  concrete  beams  with 
hollow  tile  fillers  is  used,  a  beamed  or  paneled  ceiling  may  be 
made  by  increasing  the  depth  of  the  concrete  beams  so  that  they 
will  project  below  the  soffits  of  the  tile. 

As  to  the  interior  finish  of  concrete,  "a  beautiful  and  artistic 
effect  may  be  had  by  so  erecting  the  inner  walls  and  partitions 
(if  of  concrete)  that  they  do  not  require  plastering  or  other  cover- 
ing. Concrete  has  sufficient  merit  to  be  treated  frankly  as  such, 
instead  of  being  hidden.  Now  introduce  color  and  decoration 
by  using  tiles  and  mosaic  to  give  the  needed  life  and  relieve  the 
monotony,  but  not  for  the  purpose  of  hiding  the  concrete,  which 
is  exposed  frankly  where  decorations  do  not  occur.  Then  decora- 
tion will  exercise  its  true  function,  by  emphasizing,  instead  of 
hiding  structural  beauty.  It  is  almost  needless  to  say  that, 
where  this  effect  is  sought,  concrete,  being  a  plastic  material,  is 
admirably  adapted  for  this  purpose."! 

Metal  Casement  Sash  are  frequently  used  in  England  and 
in  European  practice  for  public  and  commercial  buildings,  and 
for  the  better  class  of  residences.  They  are  being  increasingly 
used  in  this  country,  especially  for  residences,  not  so  much  on 
account  of  fire  protection  as  on  account  of  appearance  and  con- 
venience. Their  installation,  however,  forms  a  distinct  addition 
to  the  fire-resisting  qualities  of  first-  or  second-class  construction 
in  dwellings. 

Fig.  343  illustrates  typical  casement  sashj  of  the  details  shown 
in  Fig.  344.  The  frames  and  sash  are  made  of  solid  rolled-steel 
sections,  the  corners  of  which  are  riveted  and  brazed.  Hardware 
is  made  of  wrought-iron  or  of  gun  metal.  Various  other  forms 
of  fixed  and  pivoted  sash  are  made,  besides  hinged  transom  sash. 

Fire  Extinguishing  Appliances.  —  The  value  of  "  first  aid  " 
appliances  in  the  event  of  fire,  as  described  in  Chapter  XXIX,  is 

*  Montgomery  Schuyler  in  "Building  Progress,"  March,   1911. 
t  "Reinforced  Concrete  for  the  Small  House,"  C.  R.  Knapp,  "Proceedings 
National  Association  of  Cement  Users,"  Vol.  VI. 

t  Made  by  Henry  Hope  &  Sons,  Ld.,  Birmingham,  England. 


786 


FIRE    PREVENTION    AND    FIRE    PROTECTION 


particularly  applicable  to  residences,  owing  to  the  generally 
inflammable  nature  of  the  contents.  First  aid  appliances  such 
as  water  pails,  extinguishers,  etc.,  are  discussed  in  more  detail 
in  Chapter  XXXII. 


FIG.  343.  —  Metal  Casement  Sash. 


Water  pails,  owing  to  their  unsightly  appearance,  are  hardly 
suitable  in  dwellings  except  in  cellars,  but  no  residence,  however 
small  or  modest,  should  be  without  chemical  extinguishers. 
These  should  be  located  preferably  one  on  each  floor,  and  a  little 
ingenuity  can  arrange  for  their  placing  on  small  metal  bracketed 
shelves  or  the  like  in  halls,  bathrooms,  pantries,  etc.,  where  they 
will  be  handy  but  inconspicuous. 

For  larger  residences,  a  wise  precaution  is  the  installation  of 
a  2-in.  standpipe,  located  at  or  near  the  stairway,  with  a  suitable 
length  of  fire  hose  at  each  floor.  The  standpipe  may  be  supplied 


RESIDENCES 


787 


from  an  attic  tank,  which  should  be  so  arranged  as  to  be  kept 
full  automatically;  and  by  placing  the  riser  in  a  slot  or  chase  in 
the  wall,  covered  by  a  paneled  wood  or  metal  front,  and  with  hose 
racks  in  neatly  finished  wall  boxes,  the  whole  installation  will  be 
inconspicuous,  but  invaluable  in  time  of  need,  provided  proper 
maintenance  is  given. 

For  a  farm  or  large  country  place,  especially  if  somewhat 
remote  from  fire  department  service,  a  40-gallon  chemical  tank 
with  hose,  on  wheels,  should  be  considered  a  necessary  adjunct. 


FIG.  344.  —  Detail  of  Metail  Casement  Sash  and  Frame. 


Comparative  Costs.  —  A  careful  investigation  conducted  by 
Mr.  J.  Parker  B.  Fiske,  Secretary  of  the  Building  Brick  Associa- 
tion, to  determine  the  relative  costs  of  small  houses  of  various 
types  of  construction,*  furnishes  trustworthy  data  concerning 
the  cost  of  third-class  or  all-frame  residences  vs.  second-class 
residences,  or  those  with  masonry  exterior  walls  and  wooden 
floors,  roofs,  partitions,  etc.  Bids  were  asked  from  five  building 
contracting  firms  of  well-known  reputation  on  identical  plans  and 
specifications  covering  nine  alternate  constructions  as  follows: 

Type  1.  Frame  covered  with  boards  and  finished  with 
clapboards  over  building  paper;  inside  surface  furred,  lathed 
and  plastered. 

Type  2.  Frame  covered  with  boards  and  finished  with 
shingles  over  building  paper;  inside  surface  furred,  lathed  and 
plastered. 

*  For  full  details  see  The  Brickbuildcr,  March,  1911. 


788 


FIRE    PREVENTION    AND    FIRE    PROTECTION 


Type  3.  A  10-inch  brick  wall,  i.e.,  two  4-inch  walls  tied 
together  with  metal  ties  and  separated  by  a  2-inch  air-space; 
inside  surface  plastered  directly  on  the  brickwork.  Face  brick 
to  cost  $17.50  per  M.;  inside  brick,  $9.00  per  M. 

Type  4.  A  12-inch  solid  brick  wall;  inside  surface  furred, 
lathed  and  plastered.  Face  brick  to  cost  $17.50  per  M.;  inside 
brick,  $9.00  per  M. 

Type  5.  Eight-inch  hollow  terra-cotta  blocks,  stuccoed  on 
the  outside  and  plastered  directly  on  the  inside. 

Type  6.  Six-inch  hollow  terra-cotta  blocks,  finished  with 
a  4-inch  brick  veneer  on  the  outside  and  plastered  directly  on 
the  inside.  Face  brick  to  cost  $17.50  per  M. 

Type  7.  Frame  covered  with  boards  and  building  paper, 
furred  and  covered  with  stucco  on  Clinton  wire  cloth;  inside 
surface  furred,  lathed  and  plastered. 

Type  8.  Frame  covered  with  boards  (building  paper 
omitted),  and  finished  with  a  4-inch  brick  veneer  on  the  outside; 
inside  surface  furred,  lathed  and  plastered.  Face  brick  to  cost 
$17.50  per  M. 

Type  9.  Frame  finished  on  the  outside  with  a  4-inch  brick 
veneer  tied  directly  to  the  studding  (boarding  omitted);  inside 
surface  furred,  lathed  and  plastered.  Face  brick  to  cost  $17.50 
per  M. 

All  details  and  requirements,  save  the  outer  wall  construction, 
were  uniform  for  all  types.  The  comparative  bids  received  were 
as  follows : 


Type  No. 

1 

2 

3 

4 

5 

6 

7 

8 

9 

.2 

11 

,M 

•g:s 

| 

t-i    O 

a 

f-i  bfi 

1^ 

*>.S 

O  w 

0     . 

A  8 

1 

Q 

» 

O 

'M 

O-- 

6  § 

$ 

p 

II 

w 

«  ° 

IS 

Bid  No. 

$ 

$ 

$ 

$ 

$ 

$ 

$ 

$ 

$ 

1 

6732.00 

7572.00 

7416.00 

7777.00 

6857.00 

7130.00 

7080.00 

2 

6235.76 

6370.40 

6736.43 

7105.00 

6491.  23!  6762.  83 

6410.00 

6746.20 

6664.88 

3 
4 

6692.00 
6690.00 

6786.007118.00 
17496.00 

7418.00 
7801.00 

7179.00 
7202.00 

7238.00  6847.50 
7648  007000.00 

6970.00 
7496.00 

6895.00 
7420.00 

5 

7450.00 

7450.00 

7940.00 

8240.00 

7650.00 

7990.00  7650.00 

7790.00 

7710.00 

Average 
of  Bids 

6759.95 

6868.80 

7372.48 

7641.00 

7187.65 

7483.16 

6952.90 

7226.44 

7153.98 

The  percentage  excess  costs  of  the  various  types  over  the  clap- 
board type  were  as  follows : 


KESIDENCES 


789 


Type  No. 

1 

2 

3 

4 

5 

6 

7 

8 

9 

c    . 

V. 

0    M 

Description. 

Clapboard. 

Q 
1 

15 

Ul 

10-inch  brick 
wall  hollow 

12-inch  brick 
wall  solid. 

Stucco  on 
hollow  bloc 

Brick  veneer 
hollow  bloc 

Stucco  on 
frame. 

Brick  veneer 
on  boarding 

Brick  veneer 
on  studding. 

Bid  No. 

1 

.0 

12.5 

10.2 

15.5 

'    1.9 

5.9 

5.2 

2 

.0 

21 

8.0 

13.9 

4.1 

8.4 

2.8 

8.2 

6.9 

3 

.0 

1.4 

6.4 

10.8 

7.3 

8.2 

2.3 

4.2 

3.0 

4 

.0 

12.0 

16.6 

7.7 

14.3 

4.6 

12.0 

10.9 

5 

.0 

.0 

6.6 

10.6 

2.7 

7.2 

2.7 

4.6 

3.5 

Average 
of  Bids 

.0 

1.6 

9.1 

13.0 

6.3 

10.7 

2.9 

6.9 

5.8 

Fire-Resisting  Construction.  —  Similar  comparisons  have  been 
made  between  the  costs  of  frame  dwellings  in  the  vicinity  of 
New  York  City  and  first-class  construction,  —  i.e.,  with  fire- 
resisting  walls,  floors,  roof  and  partitions.  These  costs  averaged 
about  as  follows : 

Frame  dwelling $10,000. 

Hollow  tile  construction  throughout,  except  roof,  walls 

stuccoed $12,000. 

Hollow  tile  construction  throughout,  walls  faced  with 

brick $14,000. 

Brick  walls,  hollow  tile  floors,  roof,  etc $15,000. 

Cost  of  Maintenance  for  Residences  of  Second-  and 
Third-class  Construction.*  — 

An  estimate  of  the  probable  yearly  charge-off  and  repairs 
on  a  dwelling  of  third-class  construction,  namely,  all  of  wood,  and 
on  a  dwelling  of  the  same  size,  character  of  finish,  etc.,  but  of 
second-class  construction,  namely,  with  exterior  of  incombustible 
material : 

1.  Third-class  dwelling  covering  about  1500  sq. 
ft.,  two  and  a  half  stories  and  cellar.  Cost,  $10,000. 
Estimated  efficient  life,  20  years. 

Annual  charge-off  with  interest  at  4  per  cent $736.00 

Repairs,  painting,  etc 250.00 

Total  per  year $986.00 

*  From  "The  Prevention  of  Fire  in  Boston,"  Report  of  the  Committee  on 
Fire  Prevention  of  the  Boston  Chamber  of  Commerce,  C.  H.  Blackall,  Chair- 
man, September,  1911. 


790         FIRE   PREVENTION   AND   FIRE   PROTECTION 

2.  Cost  of  house  of  same  dimensions,  but  of  sec- 
ond-class construction,  $11,500.  Estimated  efficient 
life,  40  years. 

Annual  charge-off  with  interest  at  4  per  cent ....     $580 . 75 
Repairs  and  painting  about , 100 . 00 

Total  per  year $680.75 

The  cost  per  year  on  the  above  basis  for  a  third  class  building 
is  $305.25  more  than  that  of  a  second-class  building,  an  increase 
of  45  per  cent. 

Applying  the  same  reasoning  to  the  ordinary  three  tenement 
house  of  which  so  many  are  built  in  our  suburbs,  the  comparison 
would  be  as  follows: 

1.  Three  tenement  house  entirely  of  wood  or  third- 
class  construction,  approximate  cost,  $6500.     Estimated 
efficient  life,  20  years. 

Annual  charge-off  with  interest  at  4  per  cent  ....     $478 . 40 
Repairs  and  painting 150 . 00 

Total  per  year $628.40 

2.  Cost  of  house  of  same  dimensions,  but  of  sec- 
ond-class   construction,    $7500.      Estimated    efficient 
life,  30  years. 

Annual  charge-off  with  interest  at  4  per  cent  ....     $423 . 50 
Repairs  and  painting 75 . 00 

Total  per  year $498.50 

In  this  case  the  cost  per  year  for  the  third-class  building  is 
$129.90  or  26  per  cent,  greater  than  that  of  the  second-class 
building.  9 

Figures  such  as  these  can  be  only  suggestive,  and  it  would 
be  almost  impossible  to  establish  anything  like  exact  ratios  of 
cost  of  maintenance,  length  of  available  life  or  amount  of  de- 
preciation, as  these  do  not  depend  wholly  on  the  nature  of  the 
construction,  but  are  much  modified  by  exposure,  character  of 
occupancy  and  by  the  frequency  of  change  in  tenants.  But  the 
figures  are  at  least  a  justification  of  the  conviction  held  by  many 
experts,  that,  taking  everything  into  account,  a  building  of 
second-class  construction  will  wear  better,  last  longer  and 
usually  cost  less  in  the  long  run  than  a  similar  building  of  third- 
class  construction,  with  combustible  exterior.  The  continued 
construction  of  wooden  buildings  would  therefore  seem  to  be  a 
mistake,  from  the  standpoint  of  cost,  of  use  as  measured  by  length 
of  life,  and,  above  all,  of  the  fire  hazard. 


CHAPTER  XXV. 
FACTORIES. 

The  Requisites  for  a  Successful  Factory  Building  comprise: 

Design,  as  affecting  convenience  or  suitability  for  the  purposes 
intended,  the  subdivision  of  large  areas,  the  isolation  of  dangerous 
features  and  processes,  and  the  elimination  of  vertical  openings. 

Construction,  as  regards  the  suitability  of  materials  and  details 
for  the  type  selected,  rigidity,  waterproof  floors,  satisfactory 
attachment  of  shafting,  etc.,  combined  with  the  lowest  practi- 
cable cost  and  the  least  depreciation. 

Fire  Protection,  as  regards  business  interests  and  insurance 
charges,  equipment,  and  management;  and  as  affecting  the 
safety  of  employees,  including  means  of  egress,  fire  alarm  system 
and  fire  drills. 

These  factors  will  each  be  briefly  considered. 

Design.  —  The  requirements  of  design  enumerated  above  have 
been  discussed  in  previous  chapters,  particularly  in  Chapter  IX. 
The  isolation  of  dangerous  processes  of  manufacture  is  especially 
important,  as  referred  to  on  page  313. 

Oftentimes  structural  defects  (not  mechanical,  but  from  the 
standpoint  of  fire  hazard)  of  the  unwise  location  of  hazardous 
factory  processes  cannot  be  overcome  by  the  addition  of  special 
fire  protection  after  the  completion  of  the  building.  In  such 
cases  these  defects  operate  as  a  fixed  charge  upon  the  property  and 
contents  as  long  as  the  building  stands.* 

Construction.  —  Present-day  types  of  factory  construction 
involving  partial  or  complete  fire  protection  as  far  as  the  building 
is  concerned  include: 

(a)  Steel-frame,  sheathed. 

(b)  Mill  construction. 

(c)  Steel-frame  buildings  with  brick  walls  and  fire-resisting 
floors. 

(d)  Reinforced  concrete. 

(e)  Combination  concrete  and  mill  construction. 

*  "Factories  and  their  Fire  Protection,"  by  Franklin  H.  Wentworth  in 
Special  Bulletin  of  the  National  Fire  Protection  Association. 

791 


792          FIRE    PREVENTION   AND   FIRE    PROTECTION 

All  of  these  methods  of  construction  save  the  latter  have  been 
described  in  previous  chapters,  but  there  remain  to  be  considered 
several  practical  considerations  which  often  affect  the  choice  of 
a  type,  the  applicability  of  the  above  mentioned  types  to  mill 
or  factory  buildings,  and  the  important  questions  of  relative  cost 
and  depreciation. 

Light  and  Windows.  —  Modern  factory  requirements  usually 
demand  a  maximum  window  area  —  generally  because  the  light 
is  needed  for  manufacturing  purposes,  but  sometimes  because 
of  ventilation.  The  extent  to  which  window  areas  may  be  carried 
depends  upon  the  height  of  the  stories  and  the  type  of  construc- 
tion adopted.  The  height  of  stories  requires  careful  considera- 
tion in  order  that  the  middle  of  the  rooms  in  wide  mills  may  be 
well  lighted.  The  width  of  buildings  is  many  times  limited  by 
the  question  of  light  rather  than  by  other  factors,  and  as  wide 
buildings  cost  less  than  narrow  ones  per  square  foot,  careful 
study  is  necessary  to  determine  the  best  dimensions  for  econ- 
omy consistent  with  the  occupancy. 

Brick  Walls. — In  several-storied  mill  or  factory  buildings  having 
load-bearing  brick  walls,  the  loads  to  be  carried  may  well  require 
such  pier  dimensions  for  common  brickwork  as  seriously  to  curtail 
the  window  areas.  Hence  in  some  of  the  more  recent  examples  of 
mill  constructed  buildings,  steel  girders  have  been  used  with  steel 
wall  columns  encased  in  the  brick  piers.  This  allows  a  minimum 
size  pier,  as  in  reinforced  concrete  work.  In  one  of  the  Ayer  Mills, 
Chas.  T.  Main,  Engineer,  where  the  bays  are  11  feet,  this  method 
was  used  to  give  9  ft.  window  openings  and  2  ft.  piers. 

Concrete  Walls.  —  Usually  consist  of  a  skeleton  framework  of 
reinforced  concrete  columns  and  wall  girders,  thus  permitting  a 
maximum  window  area,  though  it  is  customary  to  build  low 
spandrel  walls  of  brick  on  top  of  the  wall  girders,  up  to  a  height 
suitable  for  window  stools. 

Window  Frames  and  Sash.  —  From  considerations  of  both 
internal  and  external  fire,  incombustible  window  frames  and  sash 
are  desirable.  These  will  serve  to  prevent  the  communication  of 
external  fire  by  means  of  sparks  or  brands  on  the  sills,  or  by 
direct  contact  with  flames,  while  also  helping  to  prevent  "  auto- 
exposure,"  or  the  spread  of  internal  fire  by  means  of  draught  from 
the  windows  of  one  floor  to  those  above,  as  was  the  case  in  the 
" Triangle"  shirt-waist  factory  fire,  previously  described  in 
Chapter  VI. 


FACTORIES 


793 


Great  improvements  have  been  made  during  the  past  few  years 
in  steel  window  construction  especially  adapted  to  factory  use. 
A  typical  type  is  shown  in  Fig.  345.  The  frames,  muntins  and 
sash,  etc.,  are  made  of  variously 
shaped  rolled-steel  sections,  usually 
patented,  with  varying  "  inter  locking  " 
methods  of  joining  the  vertical  and 
horizontal  muntins.  Most  of  such 
windows  are  made  on  the  "unit" 
principle,  that  is,  combining  glass 
units  of  standard  size  so  as  to  make 
almost  any  required  width  and  height. 
Well-known  makes  of  windows  of  this 
character  are  the  "United  Steel  Sash," 
made  by  the  Trussed  Concrete  Steel 
Co.,  Detroit,  Mich.,  —  the  "Lupton 
Steel  Sash,"  made  by  David  Lupton's 
Sons  Co.,  Philadelphia,  —  the  "Fenes- 
tra  Sash,"  made  by  the  Detroit  Steel 
Products  Co.,  —  and  the  "Rapp" 
rolled  steel  sash  made  by  the  U.  S. 
Metal  Products  Co.,  New  York. 

While  windows  of  the  above  type 
may  not  be  termed  fire-resisting,  be- 
cause made  of  unprotected  steel,  still 
they  combine  a  minimum  obstruction 
to  light  with  a  considerable  resistance 
to  fire  without  buckling  or  releasing 
the  glass. 

There  is,  however,  one  point  in 
connection  with  rolled  steel  windows 
which  has  generally  been  overlooked, 
namely  that  such  constructions  form 
as  effective  a  barrier  against  escape 
from  the  inside  or  against  the  access 
of  firemen,  as  though  fixed  window 
guards  or  grilles  were  installed.  The  steel  sections  are  so  strong 
that  they  cannot  easily  be  broken,  and  the  glass  lights  are  so 
small  that  persons  can  neither  escape  nor  enter  thereby.  Con- 
ditions may  easily  arise  in  mills  or  factories,  especially  where 
large  numbers  of  operatives  are  employed,  under  which  the 


FIG.  345.  —  Rolled  Steel 
Factory  Windows. 


794          FIRE    PREVENTION    AND    FIRE    PROTECTION 

employees  might  be  trapped  by  such  windows,  or  firemen  pre- 
vented from  entering  to  advantage.  Lower  movable  sections 
are  therefore  advisable,  of  a  size  sufficient  to  permit  egress  or 
entrance.  This  safeguard  in  connection  with  such  sash  is 
obligatory  in  London,  as  the  result  of  a  factory  fire  where  the 
operatives  were  effectually  trapped  by  steel  windows. 

Glazing.  —  If  the  exposure  hazard  need  not  be  considered, 
"Luxfer  Sheet  Prism"  glass  will  afford  a  maximum  light.  If 
exposure  hazard  must  be  taken  into  account,  the  windows  should 
preferably  be  glazed  with  rough  or  figured  wire  glass,  or,  where  a 
maximum  light  is  also  essential,  with  " ribbed"  wire  glass.  For 
much  information  on  the  subject  of  light  in  factory  buildings,  etc., 
see  Report  No.  Ill  of  the  Insurance  Engineering  Experiment 
Station,  "  Wired  Glass  —  Diffusion  of  Light." 

Water-tight  Floors.  —  In  many  lines  of  manufacture,  water 
damage  may  be  quite  as  disastrous  to  stock  or  merchandise  as 
fire  damage,  hence  floors  should  be  made  water-tight  so  that  fire 
in  one  room  or  floor  may  be  extinguished  by  means  of  hose  or 
sprinklers  without  necessarily  causing  water  damage  on  the  floor 
or  floors  below.  The  use  of  scuppers  in  the  exterior  walls  at 
floor  lines  for  the  carrying  off  of  water  is  particularly  applicable 
to  warehouses  and  factories.  See  paragraph  " Waterproofing," 
Chapter  XI,  page  335.  Either  concrete  or  wood  floors  may  be 
pitched  to  wall  scuppers. 

Attachment  of  Shafting,  etc.  —  The  type  of  floor  construc- 
tion vitally  affects  the  question  of  hangers  for  shafting,  sprinkler 
pipes,  etc. 

Owing  to  the  fact  that  most  mills  are  built  before  the  exact 
locations  of  machines  and  shaftings  have  been  worked  out,  it  is 
impossible  to  provide  for  hangers  in  definite  locations  beforehand. 
Provision  must  be  made  for  permitting  the  shafting  to  be  placed 
in  almost  any  location,  as  sooner  or  later  most  mills  undergo  a 
reorganization  in  part  or  in  whole.  This  means  that  provision 
must  be  made  with  enough  flexibility  to  allow  the  placing  of 
shafting  wherever  desired. 

In  this  respect,  mill  construction  possesses  a  decided  advantage, 
while  both  hollow  tile  and  concrete  floor  constructions  are  at  a 
great  disadvantage. 

Where  hollow  tile  floor  arches  are  used,  hangers  for  shafting, 
etc.,  are  usually  attached  to  the  floor  beams,  either  by  tapping 
into  the  beam  flanges  or  by  means  of  clamps  around  the 


FACTORIES 


795 


Pin-12  Long 


flanges.  In  either  case,  the  soffit  protection  is  destroyed  at 
such  points.  Also,  where  shafting  runs  parallel  to  beams,  either 
cross  supports  are  necessary  from  beam  to  beam,  or  the  hang- 
ers must  be  supported  by  means  of  bolts  through  the  tile  archer 
or  by  toggle-bolts  through  the  soffit  webs.  Such  supports  are 
very  unsatisfactory  and  very  inflexible,  especially  the  latter 
methods. 

For  concrete  floors,  one  type  of  hanger  sockets  in  use  is  shown 
in  Fig.  346.  This  consists  of  a  casting,  varying  in  length  with 
the  depth  of  the  slab,  tapped  at  the  lower  orifice  for  the  receipt 
of  a  tap-bolt  with  washer  plate.  The  core  of  the  casting  is  made 
smaller  at  the  tapped  end  than  at  top, 
so  there  will  be  no  possibility  of  the 
binding  of  the  tap-screw  when  screw- 
ing in.  A  f-in.  diam.  cross  pin  or  rod, 
usually  12  ins.  long,  passes  trans- 
versely through  a  cored  hole  in  the 
upper  end  of  the  casting,  and  lies  on 
top  of  the  reinforcing  rods. 

Hangers  which  depend  upon  rein- 
forcing  rods   for  direct  support   are 

not  good  practice  for  the  following  FIG.  346.  — Shafting  Hangers  as 
reasons :  used  with  Concrete  Floors. 

1.  Too   great   a   strain   is   placed 

locally  on  the  rods  which  are  near  the  lower  surface  of  the  slab. 
The  concrete  under  them  will  become  loosened  from  the  contin- 
uous pull  and  "vibration  of  the  shafting. 

2.  It  is  unsafe  to  permit  direct  connection  between  reinforcing 
rods  and  the  fittings  or  machinery  of  rooms,  as  stray  electric 
currents  are  thereby  permitted  to  enter  the  rod  system.     It  has 
been  shown  that  direct  currents  are  dangerous  to  the  life  of 
reinforced  concrete  when  they  are  allowed  to  reach  the  reinforc- 
ing system.    Inserts  or  hangers  should  therefore  be  designed  to  be 
supported  independently,  or  insulated. 

Roofs.  —  Mill  construction  roofs  and  also  the  advantages  and 
disadvantages  of  " Saw-Tooth"  roofs  for  factory  buildings  are 
described  in  Chapter  IV. 

Brick  factories,  sheathed  buildings,  and  such  structures  as 
foundries,  machine  shops,  etc.,  have  generally  been  provided 
with  flat  or  pitched  roofs  of  slate  or  tar  and  gravel  on  wood 
boarding  and  joists,  with  wood  or  steel  trusses;  but  disastrous 


796          FIRE   PREVENTION   AND   FIRE   PROTECTION 

fires  have  either  partially  or  totally  destroyed  many  buildings  of 
this  character.  An  instance  was  the  destruction  of  the  foundry 
and  machine  shop,  etc.,  of  the  Brown  Hoisting  Machinery  Co., 
referred  to  in  Chapter  XXI.  Such  roofs  have  usually  been  the 
most  unfit  and  dangerous  parts  of  the  buildings. 

It  will  generally  be  poor  policy,  from  the  standpoints  of  con- 
tinuity of  business,  insurance  and  depreciation,  to  provide  a 
combustible  roof  on  any  factory  building  unless  such  building 
is  of  a  very  cheap  or  temporary  nature.  Fire-resisting  roofings 
especially  suitable  for  sheathed  structures  such  as  machine  shops, 
foundries,  and  the  like,  are  asbestos  corrugated  sheathing, 
asbestos  protected  metal,  and  "ferroinclave,"  as  described  in 
Chapters  VII  and  XXI.  A  comparison  in  cost  between  the  usual 
tar  and  gravel  and  plank  roofing  on  roof  trusses,  and  a  ferroin- 
clave  roofing  is  as  follows:* 

Ordinary  Type:  Per  Square 

Plank,  including  nailing  strips  on  purlins $6. 90 

Laying 3.00 

Painting  under  side  of  plank  two  coats 1 .  75 

Tar  and  gravel  roof 4.  50 

Repairs  to  tar  and  gravel  roof  on  assumption 

that  life  is  ten  years .45 

Total $16.60 

"  Ferroinclave  "  Roof :  Per  S(*uare 

Ferroinclave  sheets $8. 50 

Fastening  clips .48 

Laying  sheets 1 . 25 

Cementing  upper  side 3 . 00 

Cementing  under  side 4  .00 

Waterproof  covering 1 . 50 

Sundries,  freight,  superintendence 1 . 27 

Total $21.00 

Similar  dove-tailed  plates  for  roofing  (and  siding)  purposes  aref 
the  "  Ferro-lithic "  steel  plates  made  by  the  Berger  Mfg.  Co. 

"Hy-Rib,"  made  by  the  Trussed  Concrete  Steel  Co.,  Detroit, 
is  also  used  for  the  same  purposes.  This  is  virtually  a  form  of 
expanded  metal  lathing  or  sheathing,  with  deep  stiffening  ribs 
at  intervals. 

Fire  curtains,  especially  advisable  in  machine  shops  or  factories 

*  From  Report  No.  VII  of  Insurance  Engineering  Experiment  Station, 
f*  Fire-resistant  Roofs  for  Foundries  and  Machine  Shops." 


FACTORIES  797 

containing  large  undivided  areas  covered  by  roof  trusses,  are 
described  in  Chapter  XXI. 

Hollow  tile  and  concrete  roofs  are  also  described  in  Chapter 
XXI. 

Rigidity.  —  Absolute  rigidity  is  not  a  necessity  in  most  kinds 
of  manufacturing.  Indeed,  the  old  millwrights  were  of  the 
opinion  that  there  is  such  a  thing  as  too  much  rigidity  in  the 
support  of  heavy  shafting  and  machinery,  as  some  types  of 
machines  wear  out  more  quickly  when  held  absolutely  rigid.  On 
the  other  hand,  extreme  vibration  may  seriously  affect  operating 
charges  in  requiring  increased  power  —  and  the  cost  of  machin- 
ery repair  or  maintenance  in  increasing  the  wear  on  journals  and 
other  moving  parts. 

Concrete  interests  usually  lay  much  stress  on  the  necessity  of 
absolute  rigidity  in  manufacturing  buildings,  but  the  examples 
cited  are  usually  extreme  and  often  overdrawn.  Wood  or  cast- 
iron  columns  have  proved  sufficiently  rigid  and  entirely  suitable 
for  most  mills  and  factories.  For  occupancies  using  heavy 
rotating  presses,  etc.,  concrete  construction  is  undoubtedly  the 
best  type.  Thus  in  the  building  of  the  Ketterlinus  Lithographic 
Mfg.  Co.,  Fourth  and  Arch  Sts.,  Phila.,  large  printing  and  litho- 
graphic presses  ranging  from  twelve  to  twenty  tons  in  weight 
are  located  on  the  second,  third  and  fifth  floors  without  material 
vibration. 

TYPES  OF  CONSTRUCTION. 

Steel-frame,  Sheathed.  —  One-story  machine  shops,  foun- 
dries, wharf  buildings,  etc.,  have  frequently  been  designed  in  past 
practice  with  a  steel  frame  covered  with  corrugated-iron  siding 
and  roofing.  Such  construction  has  seldom  been  entirely  satis- 
factory,, owing  to  condensation,  rapid  deterioration  and  non- 
fire-resisting  properties.  The  improvements  made  of  late  years 
in  the  manufacture  of  weather-  and  fire-resisting  materials  in- 
clude several  substitutes  which  are  far  preferable  to  corrugated- 
iron  from  many  standpoints,  and  which  will  prove  of  little  added 
cost  in  the  long  run.  Such  materials  include  asbestos  corrugated- 
sheathing,  and  the  various  forms  of  dove-tailed  plates  and  ribbed 
metal  sheathing  to  receive  inside  and  outside  coats  of  plaster  — • 
all  previously  described.  These  are  all  well  suited  for  the 
sheathing  as  well  as  for  the  roofing  of  buildings  of  this  type, 
where  a  durable  fire-resisting  covering  is  required  at  compara- 


798         FIRE   PREVENTION   AND   FIRE   PROTECTION 

tively  low  cost.  The  resultant  construction,  however,  is  only 
partially  fire-resistant,  in  that  the  steel  framework,  roof  trusses, 
etc.,  are  usually  unprotected,  and  hence  subject  to  rapid  de- 
struction in  case  of  internal  fire  of  any  severity.  The  great  value 
of  sheathings  of  this  character  lies  in  their  ability  to  withstand 
ordinary  exposure  hazard. 

Mill  Construction.  —  The  principles  of  mill  construction,  as 
applied  to  various  types  of  mill  and  factory  buildings,  and  cost 
data  of  such  construction,  have  been  described  in  some  detail  in 
Chapter  IV.  Attention  has  also  been  called  to  the  gradual 
increase  in  cost  of  late  years  of  the  best  examples  of  mill  con- 
struction, owing  to  the  increased  scarcity  of  yellow  pine  in 
large  sizes,  while  the  cost  of  concrete  buildings,  owing  to  more 
economical  design  and  erection  and  to  the  greatly  reduced  cost 
of  cement  products,  has  been  correspondingly  lowered.  Further 
comparative  data  as  to  the  cost  of  mill  vs.  concrete  construction, 
given  in  a  later  paragraph,  show,  however,  that  equality  in  cost 
between  these  two  types  of  construction  has  not  yet  been  reached, 
but  that  a  material  advantage  as  to  first  cost  still  lies  with  mill 
construction. 

Aside  from  the  question  of  first  cost,  however,  several  very 
practical  matters  operate  as  advantages  and  disadvantages  in 
this  type  of  construction. 

Advantages.  —  Standard  "  slow-burning "  construction,  when 
reinforced  with  suitable  protective  equipment,  has  proved 
eminently  satisfactory  for  mill  and  factory  buildings.  Dis- 
astrous fires  in  approved  mill  constructed  buildings  have  been 
extremely  rare.  One  of  the  Mutual  fire  insurance  companies  has 
estimated  that  a  regular  mill  construction  building  is  liable  to  be 
burned  up  once  in  every  two  thousand  years. 

Again,  experience  has  shown  that  the  greatest  fire  hazard  in 
mills,  etc.,  is  not  dependent  so  much  upon  the  character  of  the 
building  as  upon  the  machinery,  contents  and  methods  of  han- 
dling or  manufacture. 

As  regards  the  easy  attachment  of  shafting,  hangers,  etc.,  mill 
construction  possesses  a  decided  advantage  over  all  other  types, 
while  the  wood  floors  invariably  provided  are  usually  considered 
preferable  from  the  standpoint  of  comfort. 

As  regards  vibration,  mill  construction  is  also  generally  satis- 
factory, as  witness  its  extended  use  for  large  textile  mills,  etc. 
Extreme  cases,  involving  heavy  presses  or  machines-,  rotating 


FACTORIES  799 

at  high  speed,  may  make  concrete  construction  advisable.     See 
former  paragraph  "  Rigidity." 

Disadvantages.  —  Recent  experience  tends  to  show  that,  even 
if  so-called  " long-leafed  Georgia  pine"  may  now  be  obtained  in 
the  market,  no  reasonable  assurance  may  be  had  that  such  timber 
is  not  an  inferior  variety  of  Cuban  or  loblolly  pine,  which  is  par- 
ticularly subject  to  the  fungus  which  causes  dry  rot.  (Compare 
with  paragraph  "Dry  Rot  in  Timbers,"  Chapter  IV,  page  98.) 
This  action  of  dry  rot  on  inferior  grades  of  yellow  pine  has 
recently  caused  the  Canadian  Spool  Cotton  Co.,  at  Maisonneuve, 
Que.,  to  replace  the  entire  wooden  frame  of  their  mill  with  steel, 
although  the  mill  was  built  less  than  four  years  ago. 

Investigation  showed  that  the  beams  attacked  by  dry  rot 
were  in  almost  every  case  not  long-leafed  Georgia  pine  at  all,  as 
specified  by  the  architect  in  the  original  construction,  but  Cuban 
or  loblolly  pine. 

Such  occurrences  as  this  bring  definitely  home  to  the  engi- 
neer that  the  long-predicted  exhaustion  of  the  timber  supply  is 
no  longer  in  the  future,  but  in  the  present. 

Timber  is  still  obtainable  in  the  market,  but  it  is  of  a  quality 
very  different  from  that  which  was  formerly  available,  and  is  too 
often  lacking  in  reliability.* 

The  heavy  close-grained  " long-leafed  Georgia  pine,"  which 
is  heavier  and  stronger  than  the  other  varieties,  is  fast  disappear- 
ing in  the  large  sizes.  This  is  unavoidable,  and  must  be  taken 
into  careful  consideration  in  selecting  stock  for  buildings  of  slow- 
burning  mill  construction  in  the  present  and  future.  It  is  prob- 
able that  poor  grades  of  timber  can  and  in  the  future  will  have 
to  be  used  in  structures.  A  light  piece  of  timber  is  weaker  than 
a  heavy  piece  in  approximately  the  proportion  of  their  respective 
weights,  but  this  can  be  allowed  for  in  designing  so  that  ample 
strength  and  stiffness  is  obtained  from  the  poorer  material. 
Light  and  porous  timber  is  susceptible  to  fungus  growth,  par- 
ticularly in  rooms  subject  to  moisture  and  low  temperatures. 
There  is  no  question  of  the  danger  of  using  such  timber  without 
previous'  antiseptic  treatment.! 

Even  aside  from  such  unusual  rapid  deterioration  as  is  noted 
above,  mill  construction  is  subject  to  greater  depreciation  than 
masonry  construction. 

Steel-frame  Factories.  —  Buildings  with  a  steel  frame  and 
fire-resisting  floors  and  roofs,  whether  with  load-supporting  or 
veneer  exterior  walls,  have  been  considered  in  detail  in  previous 

*  Editorial,  Engineering  News,  December  21,  1911. 

t  See  "Rapid  Destruction  of  Timber  Beams  from  Dry  Rot,"  Engineering 
News,  December  21,  1911. 


800          FIRE    PREVENTION    AND   FIRE    PROTECTION 

chapters.  As  particularly  applied  to  mill  or  factory  buildings, 
the  advantages  and  disadvantages  of  this  type  of  construction 
may  be  briefly  summarized  as  follows: 

Advantages  include  thoroughly  fire-resisting  construction,  and 
of  a  type  which,  when  properly  built,  will  require  a  minimum 
reconstruction  after  damage  by  fire;  comfortable  wood  floors; 
larger  bays  than  are  economical  in  other  constructions,  thus 
reducing  the  number  of  columns. 

Disadvantages  include  the  difficulty  of  rendering  floors  water- 
tight; difficulties  in  attaching  and  changing  shafting  hangers, 
etc.;  excessive  width  of  wall  piers,  thus  reducing  available  light 
areas,  unless  supporting  cast-iron  or  steel  columns  are  used  in 
exterior  walls;  excessive  cost. 

If,  however,  the  building  is  to  be  built  during  the  winter 
months,  and  if  the  time  of  occupancy  is  an  important  considera- 
tion, the  excess  cost  of  steel-frame  over  reinforced  concrete 
construction  may  be  more  apparent  than  real. 

Reinforced  Concrete  Factories.  —  General  types  of  con- 
crete construction  have  been  described  in  previous  chapters. 
Attention  will,  therefore,  be  confined  here  to  a  brief  statement  of 
the  advantages  and  disadvantages  of  this  type  of  construction 
as  applied  to  mill  or  factory  buildings. 

Advantages  include  good  light,  inasmuch  as  the  walls  usually 
consist  of  columns  only,  with  low  spandrel  walls, — ease  of  making 
floors  waterproof,  —  low  depreciation  and  insurance  rates,  —  and 
generally  lowest  cost  for  thoroughly  fire-resisting  construction. 

Disadvantages  include  the  time  necessary  for  construction  in 
bad  weather,  —  the  difficulty  of  protecting  the  work  and  of 
securing  first-class  workmanship  in  bad  or  freezing  weather,  — 
discomfort,  dusting  and  difficulty  of  repairing  floors  when  of 
concrete  finish,  —  unsatisfactory  provisions  for  attachment  and 
changing  of  shafting  hangers,  etc.,  —  cold  roofs,  —  and  difficulty 
of  reconstruction  after  fire,  as  explained  in  Chapter  XVIII, 
page  621.  The  latter  feature  may  count  very  much  against 
concrete  construction  where  the  occupancy  is  such  that  the 
building  is  subject  to  frequent  fires. 

Combination  Concrete  and  Mill  Construction.*  - 

This  type  of  construction  may  be  briefly  described  as  con- 
sisting of  a  skeleton  frame  of  reinforced  concrete  (that  is,  the 

*  The  construction  here  described  is  patented  by  Francis  W.  Wilson,  Con- 
sulting Engineer,  Boston,  Mass. 


FACTORIES 


801 


columns,  girders  and  beams)  with  floors  of  hard  pine  plank 
spanning  from  beam  to  beam,  and  with  curtain  walls  of  brick  or 
concrete,  as  may  be  desired.  ...  So  far  as  the  wall  construction 
is  concerned,  this  presents  no  novel  features,  but  is  exactly  similar 
to  the  wall  construction  generally  used  for  concrete  factory  build- 
ings. The  construction  of  the  floors,  however,  is  conceded  to  be 
unique  not  only  in  the  matter  of  combining  a  plank  flooring  with 
concrete  beams  and  girders,  but  largely  because  the  beams  and 
girders  themselves  are  of  T-sections.  Some  of  the  minor  details 


-Reinforced  Concrete  Columns^ 
/Reinforced  Concrete  Girder^ 


^Reinforced  Concrete  Beam 
FIG.  347.  —  Combination  Concrete  and  Mill  Construction 


of  the  construction  made  necessary  in  accomplishing  this  result 
are  also  of  interest. 

Fig.  347  shows  a  portion  of  a  floor  construction  of  this  type 
as  constructed  in  the  Fore  River  Shipbuilding  Company's  office 
building.  It  will  be  noted  that  the  construction  shows  a  series  of 
rectangular  openings  which  are  bordered  with  hard  pine  (3X6 
ins.  in  size).  The  hard  pine  framing  of  these  rectangular-shaped 
borders  acts  as  spiking  pieces  to  which  the  floor  planks  are  nailed. 

Fig.  348  shows  a  cross-section  through  a  reinforced-concrete 
beam,  and  the  relative  position  of  the  hard  pine  spiking  pieces 
are  there  clearly  shown.  It  will  be  noted  that  the  spiking  pieces 
project  above  the  top  of  the  concrete  T  of  the  beam  (usually 
2  ins.),  and  that  this  space  is  filled  with  cinder  concrete.  The 
object  of  this  is  to  afford  a  bearing  for  the  planking  entirely  across 
the  top  of  the  T  of  the  concrete  beams.  This  cinder  fill  is  finished 


802         FIRE   PREVENTION   AND   FIRE   PROTECTION 

about  |  in.  higher  than  the  tops  of  the  spiking  pieces,  so  that  while 
it  is  necessary  to  nail  the  planking  to  the  spiking  pieces,  yet  it  is 
not  the  intention  to  have  the  spiking  pieces  actually  carrying  the 
load  of  the  floor.  Another  reason  why  the  tops  of  the  spiking 
pieces  are  placed  so  that  their  tops  are  practically  2  ins.  higher 
'  than  the  tops  of  the  concrete  tees  is  that  it  is  difficult  to  construct 
the  concrete  work  so  that  the  concrete  tops  of  the  T's  would  be 
perfectly  level  after  the  concreting  is  completed.  With  this 
arrangement  it  is  not  necessary  that  great  exactness  in  the  con- 
crete levels  should  be  required,  since  the  tops  of  the  spiking  pieces 
can  afterwards  be  planed  or  adzed  down  to  true  levels  before  the 
plank  is  laid. 

The  spiking  pieces  are  secured  to  the  sides  of  the  concrete 
T's  by  bolts  which  pass  through  gas  pipe  sleeves,  the  latter  being 
concreted  into  the  T's.  The  spiking  pieces  are  .used  as  a  part  of 
the  concrete  forms,  acting  as  a  dam  for  the  concrete  at  the  sides 
of  the  T's.  The  gas  pipe  separators  and  the  bolts  connecting  the 

:  Concrete 


3S3^22^^&3^^t'^^ 

. 

|P_                  ^ 

I 

1 

^r£^-& 

Hi 

-  Spiking  P.ieces 

FIG.  348.  —  Section  of  Concrete  Beam,  Combination  Concrete 
and  Mill  Construction. 

spiking  pieces  to  the  concrete  T's  are  all  placed  before  concreting 
is  commenced.  This  arrangement  makes  it  possible  to  remove 
or  replace  a  bolt  or  any  of  the  spiking  pieces  at  any  time,  if  it 
should  become  desirable. 

In  order  to  strengthen  the  concrete  T's  and  to  provide  for 
possible  concentrated  loads  acting  at  their  outer  edges,  the  T's 
are  reinforced  with  steel  bars,  both  transversely  and  longitudinally, 
the  short  transverse  bars  being  bent  down  at  each  end. 

Fig.  349  shows  a  perspective  view  of  the  corner  of  a  room 
in  which  the  plank  floor  connection  to  the  concrete  beams  and 
girders  is  clearly  shown.  The  girders  in  the  walls  support  their 
proportionate  part  of  the  floor  loads  and  the  curtain  walls  and 
windows.  .  .  . 

The  economy  of  this  construction  is  due  to  several  causes: 

(1)  The  lighter  dead  weight  of  the  floor  construction  requir- 
ing for  the  same  strength  less  reinforcing  steel. 

(2)  Less  form  lumber,  as  will  be  obvious  from  even  a  casual 
study  of  the  construction.     Permits  standardization  of  the  forms, 
and  renders  the  erection  and  removal  easy  and  quick. 


FACTORIES 


803 


(3)  All  the  economy  resulting  from  curtain  wall  construction 
as  compared  to  bearing  walls  is  secured  by  this  type  of  construction. 

(4)  A  saving  of  time,  since  the  frame  is  quickly  erected,  and 
when  this  is  done  it  is  possible  to  commence  work  on  all  parts  of 
the  structure  simultaneously,  as,  for  example,  laying  brick,  laying 
floors,  roofing,  setting  window  frames,  plumbing,  heating,  etc.* 

While  not  thoroughly  fire-resisting,  still  the  construction  de- 
scribed above  possesses  decided  advantages  as  a  compromise 
type  of  low  cost.  If  automatic  sprinklers  are  installed,  the  fire 


FIG.  349.  —  Combination  Concrete  and  Mill  Construction. 

hazard  will  be  comparatively  slight,  especially  if  one  of  the  types 
of  metal  windows  is  employed. 

A  serious  objection  in  long  rooms  might  well  occur  through  the 
end  shrinkage  of  the  floor  planking,  which  would  tend  to  pull 
the  spiking  pieces  away  from  the  wall  girders,  and  even  to  crack 
intermediate  girders. 

Comparative  Costs.  — 

Mill  Construction.  —  For  costs,  see  Chapter  IV,  page  100,  etc. 

Steel  Frame,  Sheathed.  —  "  Roughly  speaking,  the  cost  of  one- 
story  iron  buildings,  complete,  is,  for  sheds  and  storage  houses, 

*  See  "A  Timber  Floor  Construction  for  Reinforced  Concrete  Factory 
Buildings,"  by  Francis  W.  Wilson,  Engineering  News,  April  27,  1911. 


804          FIRE    PREVENTION   AND   FIRE   PROTECTION 

40  to  60  cents  per  square  foot  of  ground,  and  for  such  buildings 
as  machine  shops,  foundries  and  electric  light  plants,  that  are 
provided  with  traveling  cranes,  the  cost  is  from  60  to  90  cents  per 
square  foot  of  ground  covered."*  This  is  for  buildings  sheathed 
with  wood  or  corrugated-iron,  hence  to  these  prices  should  be 
added  the  excess  cost  of  the  fire-resisting  sheathing  used. 

Reinforced  Concrete.  —  "As  a  general  proposition,  it  may  be 
stated  that  the  cost  of  reinforced  concrete  factories,  finished  com- 
plete with  heating,  lighting,  plumbing  and  elevators,  but  with- 
out machinery,  may  run,  under  actual  conditions,  from  8  cents 
per  cubic  foot  of  total  volume  measured  from  footings  to  roof,  to 
12  cents  per  cubic  foot.  The  former  price  may  apply  where  the 
building  is  erected  simply  for  factory  purposes  with  uniform  floor 
loading,  symmetrical  design  —  permitting  the  forms  to  be  used 
over  and  over  again  —  and  with  materials  at  moderate  prices. 
The  higher  price  will  usually  cover  such  a  manufacturing  build- 
ing as  the  Ketterlinus,  located  in  a  restricted  district,  and  where 
the  appearance  both  of  the  exterior  and  interior  must  be  pleas- 
ing. This  does  not  include  in  either  case  interior  plastering  or 

partitions."! 

Combination  Concrete  and  Mill  Construction.  —  The  office 
building  of  the  Fore  River  Shipbuilding  Co.,  built  of  the  com- 
bination type  previously  described,  is  four  stories  and  basement, 
60  X  112  ft.,  with  an  ell  17  X  32  feet.  The  cost  was  9.2  cents  per 
cubic  foot  including  equipment.  Ordinary  factory  finish  would 
have  cost  consider  ably  less. 

The  new  factory  for  C.  W.  Dean  &  Co.,  at  Natick,  Mass.,  also 
built  under  the  "  Wilson  System,"  includes  a  five-story  building 
50  X  300  ft.,  with  an  L  for  elevators  and  stairs  on  both  front  and 
rear.  Including  an  adjoining  one-story  office  building,  the  cost 
was  7.6  cents  per  cubic  foot.  The  lowest  price  received  for  all- 
concrete  construction  was  $24,000  higher  than  the  contract 
price. 

Mill  Construction  vs.  Concrete.  —  Mr.  Charles  T.  Main,  in  the 
article  on  mill  construction  costs,  quoted  in  Chapter  IV,  states 
that: 

From  such  estimates  and  proposals  as  I  have  been  able  to 
get  and  from  work  done  it  appears  that  the  cost  of  reinforced 

*  Kidder's  "Architects'  and  Builders'  Pocket  Book,"  page  1467. 
t  "Reinforced   Concrete   in   Factory   Construction,"    published   by  Atlaa 
Portland  Cement  Company. 


FACTORIES  805 

concrete  buildings  designed  to  carry  floor  loads  of  100  Ibs.  per 
sq.  ft.  or  less  would  cost  about  25  per  cent,  more  than  the  slow- 
burning  type  of  mill  construction. 

Mr.  Walter  F.  Ballinger*  states  that,  as  a  rule,  concrete  con- 
struction costs  10  to  15  cents  per  square  foot  of  floor  surface  more 
than  mill  construction.  The  cost  would  be  about  equal  if  the 
form-  or  false-work  for  concrete  construction  could  be  eliminated, 
but  in  some  cases,  if  the  location  is  convenient  to  a  railroad  siding, 
and  if  the  materials  necessary  in  concrete  construction  are  easily 
available,  the  latter  may  be  as  cheap  as  mill  construction. 

Mr.  J.  P.  H.  Perry  t  quotes  fourteen  examples  of  comparative 
costs  between  mill  construction  and  concrete  factories,  etc.  Of 
these,  eleven  were  actual  bids  on  both  types.  The  mean  excess 
cost  of  reinforced  concrete  over  mill  construction  was  6.7  per  cent. 

Steel  Frame  and  Terra-cotta  vs.  Concrete.  —  As  between  con- 
crete construction  and  steel  frame  with  terra-cotta,  the  cost  is 
usually  25  per  cent,  less  for  reinforced  concrete  than  for  a  steel 
frame  fireproof  ed  with  terra-cotta.  The  difference  in  cost  is 
represented  principally  by  the  saving  in  steel,  there  being  approxi- 
mately one-third  the  tonnage  of  steel  used  in  reinforced  concrete 
of  that  used  in  full  steel  construction. | 

From  fifteen  comparisons  quoted  by  Mr.  Perry,  most  of  which 
were  actual  bids  submitted  for  both  types,  the  mean  excess  cost 
of  protected  steel  buildings  over  reinforced  concrete  was  6.4  per 
cent. 

Depreciation.  —  The  annual  depreciation  of  a  mill  building 
is  given  by  Kidder  as  varying  from  one  to  one  and  one-half  per 
cent.,  while  Matheson's  " Depreciation  on  Factories"  presents 
data,  based  on  a  comprehensive  study  of  English  factory  buildings, 
which  indicate  that  at  the  end  of  thirty  years  the  value  of  a 
factory  building  costing  $50,000  would  be  $31,775.  This  repre- 
sents a  depreciation  of  36.4  per  cent.,  or  1.2  per  cent,  annually. 

There  is  little  question  that  the  least  depreciation  for  any  of 
the  types  of  construction  here  considered  would  result  from 
reinforced  concrete.  For  such  buildings  the  annual  deprecia- 
tion should  be  very  small,  and  confined  entirely  to  such  items  of 
trim  as  windows,  doors,  roofing,  etc. 

*  See  "  1909  Proceedings  of  National  Fire  Protection  Association." 
t  "Comparative  Cost  and  Maintenance  of  Various  Types  of  Building  Con- 
struction," in  "  1911  Proceedings  of  National  Association  of  Cement  Users." 

J  Walter  F.  Ballinger  in  "  1909  Proceedings  of  National  Fire  Protection 
Association." 


806        FIRE    PREVENTION    AND    FIRE    PROTECTION 

FIRE  PROTECTION  AND  SAFETY  OF  EMPLOYEES. 

Business  Interests.  —  The  general  principles  of  fire-resisting 
design,  as  enumerated  and  discussed  in  Chapter  IX,  are  receiving 
constantly  increasing  attention  from  those  architects,  mill-  and 
industrial-engineers  who  are  called  upon  to  design  and  construct 
manufacturing  plants.  It  is  probable  that,  if  complete  building 
statistics  could  be  secured  covering  the  past  five  years,  the  great- 
est proportional  increase  in  fire-resisting  buildings,  class  by  class, 
would  be  found  in  factories  or  buildings  devoted  to  manufacture. 
The  reason  is  not  difficult  to  understand.  The  progressive 
manufacturer  now  knows  that  the  calamity  of  fire,  heretofore 
classed  with  strikes  and  tornadoes  as  "acts  of  God,"  is  often 
nothing  but  carelessness,  usually  preventable,  and  always  disas- 
trous to  business  interests.  Insurance,  as  has  previously  been 
pointed  out,  cannot  compensate  for  the  time  lost  in  renewal  of 
plant  and  machinery,  for  the  loss  of  work  in  hand,  for  the  loss 
of  new  orders,  and,  frequently,  for  the  loss  of  old  customers. 
Successful  business  therefore  requires  continuity  of  manufacture 
and  production,  and  a  large  factor  in  securing  this  is  to  have  a 
thoroughly  well  designed  and  protected  building.  This  may  be 
secured  partly  by  means  of  construction  as  heretofore  described, 
partly  by  means  of  fire-protection  equipment,  or  more  largely 
by  both  construction  and  equipment. 

Equipment.  —  The  extent  or  amount  of  fire-protection  equip- 
ment required  in  factories  and  similar  buildings  is  a  matter  of 
good  judgment  for  each  particular  case,  but,  in  general,  it  may  be 
stated  that  automatic  sprinklers  should  invariably  be  installed 
where  wood  roofs  or  floors  are  used,  where  the  building  con- 
tains sufficient  combustible  contents  to  cause  a  fire  of  some 
magnitude,  where  particularly  dangerous  stocks  or  processes 
are  housed,  or  where  large  numbers  of  employees  handle  or 
manufacture  combustible  products,  especially  if  in  upper  stories. 

Contents,  machinery,  stock  in  process,  and  finished  goods 
usually  constitute  by  far  the  larger  part  of  the  plant  value,  and 
these  cannot  be  protected,  whatever  the  construction  of  building, 
except  by  some  means  of  equipment.  Hence,  although  the 
Factory  Mutual  Companies  do  not  always  require  sprinkler 
equipment  in  ordinary  concrete  factories,  such  equipment  is 
both  desirable  and  cheapest  in  the  long  run  where  machinery- 
or  stock- values  are  large.  But  factories  of  standard  mill  or 


FACTORIES  807 

slow-burning  construction,  if  provided  with  sprinklers  and  other 
suitable  apparatus,  may  obtain  better  insurance  rates  than 
unprotected  fire-resisting  buildings,  as  is  pointed  out  in  a  follow- 
ing paragraph,  "  Insurance." 

From  figures  compiled  by  the  General  Fire  Extinguisher 
Company  it  is  shown  that  before  the  more  general  introduction 
of  automatic  sprinklers  in  factories,  the  average  cost  per  fire  was 
$7361,  while  under  automatic  sprinkler  protection  the  average 
cost  per  fire  in  13,476  cases  covered  by  their  records  amounted 
to  but  $277.26  each.* 

For  factories  containing  but  light  hazards,  fire  buckets  or 
chemical  extinguishers  should  be  provided,  as  described  in 
Chapter  XXXII.  In  factories  of  three  or  more  stories,  a  stand- 
pipe  system  is  desirable  —  see  Chapter  XXXIV. 

These  should  be  placed  in  the  main  stair  towers,  or  at  any 
rate  on  the  opposite  side  of  the  wall  from  the  rooms  or  buildings 
they  are  designed  to  protect.  Where  buildings  are  near  enough 
to  each  other  for  the  roofs  to  afford  vantage  points  for  use  of 
hose  streams,  standpipes  should  be  extended  to  supply  roof 
hydrants.  In  factories  having  loose  combustible  stock  in  process, 
an  equipment  of  small  linen  hose  on  each  floor  is  invaluable.  It 
is  best  to  supply  this  from  an  independent  system  of  small  pipes. 
It  may  then  be  available  in  case  water  is  temporarily  shut  off 
the  sprinklers,  or  in  final  extinguishment  of  smouldering  sparks 
after  sprinklers  have  been  shut  off,  to  save  excessive  water  dam- 
age, f 

For  large  plants  involving  several  or  many  buildings,  a  private 
fire  department  is  often  desirable,  as  described  in  Chapter  XXXV. 

Management.  —  Mr.  F.  M.  Griswold  who,  through  his  con- 
nection with  insurance  interests,  has  had  a  wide  experience  in  fire 
prevention  matters,  has  stated  that,  whatever  the  construction 
of  a  factory  or  manufacturing  building,  or  the  nature  of  its 
occupancy,  or  the  completeness  of  its  fire  protection,  shop  manage- 
ment or  "good  housekeeping"  is  the  most  important  basic 
element  in  fire  prevention,  the  acceptable  practice  of  which 
requires  the  following: 

The  enforcement  of  rules  which  will  insure  cleanliness 
throughout  the  plant  as  a  matter  of  daily  practice,  not  only  as 
a  means  by  which  the  possibility  of  fire  may  be  avoided,  but  as 
of  profit. 

*  See  "Fire  Prevention  and  Fire  Protection  for  Manufacturing  Plants," 
by  F.  M.  Griswold,  G.  I. 
v  t  "Factories  and  their  Fire  Protection,"  Franklin  H.  Wentworth. 


808         FIRE   PREVENTION   AND   FIRE   PROTECTION 

(a)  Floor  sweepings,  greasy  lunch  papers,  oily  wiping 
waste,  paint,  rags  and  like  material,  subject  to  spontaneous  igni- 
tion, should  be  deposited  in  ' Standard'  safety  cans  suitable  for 
their  reception,  the  contents  of  which  should  be  safely  disposed 
of  each  night,  preferably  to  be  burned  under  the  boiler. 

Ashes  should  be  kept  only  in  metal  receptacles;  should  be 
removed  from  building  each  night  and  not  be  deposited  in  contact 
with  combustible  structures  or  material. 

(6)  Workingmen's  clothes  and  overalls,  when  not  in  use, 
should  be  kept  in  ventilated  metal  closets  or  lockers  not  in  contact 
with  readily  combustible  material. 

(c)  Oily  metal  turnings  or  filings  should  not  be  permitted 
to  accumulate  on  wooden  floors  or  be  held  in  combustible  re- 
ceptacles, nor  should  they  be  mixed  with  combustible  materials. 

(d)  All  combustible  process  waste  and  other  refuse  should 
be  carefully  disposed  of  by  removal  from  the  buildings  at  the  close 
of  each  day's  work,  and  be  safely  deposited  in  locations  not  en- 
dangering the  plant  in  case  of  ignition  of  such  refuse. 

(e)  Time  should  be  allotted    to    operatives    for    cleaning 
machinery  and  disposing  of  oily  wiping  waste,  and  for  the  re- 
moval of  combustible  waste  material  prior  to  hour  of  closing  shop 
for  the  day. 

(/)  All  volatile  and  inflammable  fluids  should  be  kept  in 
and  used  from  l Standard'  safety  cans;  not  in  excess  of  one 
day's  supply  of  such  should  be  kept  inside  of  building  at  any 
time,  and  all  unused  portions  should  be  removed  to  a  place  of 
safety  outside  of  the  plant  at  the  close  of  the  days  work.  .  .  . 

(m)  Watchman's  service  should  be  maintained  at  all  times 
when  the  plant  is  not  in  operation,  and  the  record  of  service  be 
shown  on  such  mechanical  device  as  will  not  permit  evasion  of 
duty;  records  should  be  examined  and  checked  over,  filed  and 
dated  each  day. 

(n)  Discipline  should  be  enforced  and  system  be  main- 
tained by  holding  shop  foreman  or  floor  boss  strictly  responsible 
for  the  maintenance  of  established  conditions,  a  written  report 
covering  these  matters  to  be  filed  with  manager  each  day. 

Insurance.  —  The  correction  of  structural  deficiencies  and 
the  installation  of  fire  protection  equipment  have  been  shown  (see 
Chapter  III,  page  63)  to  effect  most  vitally  the  question  of 
insurance  rates  in  buildings  of  considerable  value  and  containing 
valuable  contents.  Such  factors  bear  the  same  relation  to 
insurance  rates  in  mill  and  factory  buildings,  and  the  importance 
of  this  relation  increases  with  the  value  of  the  plant  and  its 
contents.  Whatever  the  causes,  high  rates  of  insurance  act  as 
fixed  charges,  and  possible  reductions  in  same  are,  therefore,  well 
worth  investigation. 

It  will  be  found  that  high  insurance  rates  usually  result  from 
two  principal  causes,  exactly  as  in  the  case  discussed  in  Chap- 


FACTORIES  809 

ter  III,  viz.,  structural  deficiencies,  and  lack  of  fire  protection 
equipment.  Thus  the  Committee  on  Insurance  of  the  National 
Association  of  Cement  Users*  found  that  the  following  require- 
ments for  factories,  etc.,  have  been  most  emphasized  by  the 
Rating  Associations:  Cut-off  walls,  with  automatically  closing 
doors,  —  cutting  off  vertical  openings,  —  watertight  floors,  — 
sprinkler  equipment,  —  fire-fighting  apparatus  independent  of 
city  or  town  fire  department,  —  and  fire  alarm  system.  It  will 
be  noted  that  none  of  these  structural  or  protective  deficiencies 
concerns  the  type  of  construction,  per  se,  although  many  of  those 
who  are  engaged  in  exploiting  concrete  construction  for  factory 
buildings,  etc.,  lay  great  stress  on  the  decreased  insurance  rates 
to  be  secured  through  the  adoption  of  that  type  of  building. 

As  a  matter  of  fact,  it  will  be  found  that  the  type  of  construction 
will  make  little  difference  in  insurance  costs,  for  the  following 
reasons : 

1.  The  value  of  contents  is  usually  far  greater  than  the  value 
of  building. 

2.  The  value  and  character  of  contents,  rather  than  the  type 
of  construction,  will  usually  determine  the  amount  of  fire  pro- 
tection necessary. 

3.  Any  possible  saving  in  insurance  rates  which  might  be 
effected  by  the  use  of  concrete  construction  would  be  very  small, 
as  compared  with  the  total,  for  the  reasons  that  practically  all 
fire  losses  today  in  mills  or  factories  of  standard  construction  are 
confined  to  contents,  and  insurance  rates  are  made  accordingly. 

Hence  the  decision  as  to  whether  standard  slow-burning  con- 
struction or  reinforced  qoncrete  is  preferable  for  use  in  any 
particular  case  is  dependent  upon  considerations  other  than  the 
cost  of  insurance. 

Safety  of  Employees.  —  The  principles  of  fire-resisting  design 
and  construction  enunciated  in  this  and  previous  chapters, 
should,  if  intelligently  carried  out,  amply  provide  for  the  safety 
of  employees  in  case  of  fire,  in  so  far  as  most  factories  are  con- 
cerned; but  special  safeguards  are  necessary  where  dangerous 
processes  of  manufacture  are  followed,  —  where  the  number  of 
employees  is  large,  —  where  most  of  the  operatives  are  girls  or 
women,  —  and  where  the  building  is  over  two  stories  high.  In 
such  cases  an  added  responsibility  of  great  weight  rests  on  the 

*  See  "  1911  Proceedings  of  the  National  Association  of  Cement  Users." 


810        FIRE   PREVENTION   AND   FIRE    PROTECTION 

management,  and  no  pains  or  reasonable  expense  should  be 
spared  to  make  the  conditions  as  safe  as  may  be  practicable. 

Added  safeguards  in  such  cases  should  invariably  include 
ample  and  safe  means  of  egress,  fire  alarm  system,  and  fire  drills. 
Also,  if  design  and  construction,  or  either  of  them,  are  inadequate 
in  any  vital  particulars,  then  the  third  element  of  fire  protection, 
namely,  equipment,  should  be  given  increased  attention. 

Another  point  worthy  of  especial  emphasis  is  the  occupation 
for  factory  purposes  of  premises  never  designed  or  intended  for 
such  uses.*  A  case  in  point  was  the  " Triangle"  shirt-waist 
factory  fire,  described  in  Chapter  VI.  The  building  was  in- 
tended for  loft  purposes  only,  but  the  crowding  of  the  upper  floors 
with  hundreds  of  employees,  mostly  women  and  girls,  resulted 
in  such  a  fearful  loss  of  life  that  the  coroner's  jury,  composed  of 
unusually  able  men,  including  architects,  engineers  and  builders, 
brought  in  a  verdict  which  contained  the  following  references  to 
some  of  the  safeguards  enumerated  above. 

Legislation  cannot  eliminate  all  loss  of  life  by  fire  or  by 
panic,  but  properly  enforced  laws  can  certainly  lessen  the  loss 
of  life  from  these  causes.  The  evidence  submitted  to  this  jury 
shows  that  there  were  employed  on  the  eighth,  ninth  and  tenth 
floors  of  said  premises  about  500  persons,  of  whom  about  80  per 
cent  were  females  and  of  whom  about  235  were  employed  on  the 
ninth  floor,  where  nearly  all  the  loss  of  life  by  smoke  and  flames 
occurred. 

We  are  convinced  by  the  evidence  that  not  only  had  no 
attention  been  given  to  and  no  means  provided  for  the  hasty  exit 
of  those  employed  in  said  premises,  but  on  the  contrary  their 
safety  had  been  utterly  disregarded. 

We  find  that  one  of  the  tables  to  which  the  machines  were 
attached  at  which  the  employees  worked  was  76  ft.  long,  that  it 
extended  from  within  13 J  ins.  of  the  front  wall  at  one  end  to 
within  16  ins.  of  a  partition  at  the  other  end,  thus  leaving  only 
two  passageways,  one  of  about  13  j  ins.  and  one  of  16  ins.,  through 
which  said  employees  were  obliged  to  pass  to  reach  the  stairs  and 
elevators. 

The  foregoing  is  a  condition  that  certainly  should  not  ob- 
tain. If  there  is  any  law  that  permits  it,  it  should  be  immediately 
repealed.  If  there  is  no  law  governing  it  such  a  law  should  at 
once  be  enacted  which  will  prohibit  such  a  condition,  and  the 
law  should  be  so  framed  that  its  enforcement  should  rest  upon 
one  single  department  of  the  city  government.  There  should 
be  no  divided  responsibility. 

It  is  the  opinion  of  this  jury  that  all  fire  escapes  should 
be  regularly  inspected  by  the  Fire  Department  and  when  such 

*  See  paragraph  "Limitation  of  Occupancy,"  Chapter  IX,  page  299. 


FACTORIES  811 

inspection  reveals  non-conformity  with  the  law  it  should  be 
immediately  reported  in  writing  to  the  Bureau  of  Buildings, 
which  shall  at  once  order  the  owner  of  the  building  on  which 
said  fire  escape  is  installed  to  have  such  changes  made  as  to  make 
it  comply  with  the  law,  and  the  Bureau  of  Buildings  shall  have 
power  to  enforce  such  order. 
Recommendations : 

1.  That  where  plans  are  filed  with  the  Bureau  of  Buildings 
for  a  new  building,  the  application  set  forth  for  what  purpose  the 
building  is  to  be  used;    that  such  building  shall  be  used  for  no 
other  purpose   than  that  stated   unless  written   permission  be 
granted  by  the  Superintendent  of  Buildings,  who  shall  issue  such 
a  permit  only  when  the  building  complies  in  construction  with 
the  law  governing  the  class  of  buildings  devoted  to  this  other 
use. 

2.  That  before  any  building  shall  be  used  plans  shall  be 
filed  with  the  Bureau  of  Buildings  showing  the  location  of  ma- 
chinery, tables,  exits,  etc.,  together  with  the  number  of  prospec- 
tive employees,  and  that  such  plans  must  be  approved  by  the 
Superintendent  of  Buildings,  who  must  first  determine  that  the 
exits  will  enable  all  employees  to  escape  in  time  of  emergency. 

3.  That  a  compulsory  fire  drill  shall  be  established'  where 
large  numbers  of  employees  are  assembled. 

4.  That  all  factory  buildings  shall  be  inspected  at  least  once 
in  six  months. 

5.  That  automatic  sprinklers  shall  be  installed. 

6.  That  all  factory  stairways  shall  be  hereafter  extended  to 
the  roof. 

7.  That  rules  shall  be  posted  in  large  factories  telling  what 
to  do  in  case  of  fire. 

8.  That  an  axe  shall  be  placed  at  all  doors  of  manufactur- 
ing places. 

Means  of  Egress.  —  See  Chapter  IX,  page  300,  and  Chapter 
XV,  " Stairways  and  Fire  Escapes." 

The  following  requirements,  abstracted  from  an  "act  regulat- 
ing the  age,  employment,  safety,  health  and  work  hours  of  persons, 
employees  and  operatives  in  factories,  workshops,  mills  and  all 
places  where  the  manufacture  of  goods  of  any  kind  is  carried  on, 
and  to  establish  a  department  for  the  enforcement  thereof," 
enacted  by  the  legislature  of  the  State  of  New  Jersey,  1911,  — 
principally  as  a  result  of  the  Newark  factory  fire,  of  November  26, 
1910  —  are  suggestive  as  showing  the  increased  consideration 
being  given  to  this  subject. 

Two-story  buildings  to  have  at  least  two  means  of  egress 
from  second  story,  placed  as  far  as  may  be  possible  at  opposite 
ends  of  room  or  building,  and  to  consist  of  either  inside  stairways* 
or  outside  fire  escapes,  or  both. 


812         FIRE   PREVENTION   AND   FIRE   PROTECTION 

Buildings  more  than  two  stories  high  to  have  at  least  two 
similar  means  of  egress  communicating  with  each  story,  one  to 
be  an  inside  stairway,  and  one  an  outside  fire  escape.  Additional 
stairs  or  fire  escapes  to  be  provided  if  necessary  for  the  proper 
protection  of  inmates. 

The  owners  of  new  factories  over  two  stories  high  (or  of  old 
buildings  to  be  devoted  to  factory  use)  must  file  plans  and  speci- 
fications showing  stairways,  fire  escapes,  elevator  shafts,  doors 
and  windows,  ventilation  and  sanitation.  These  plans  and 
specifications,  together  with  the  estimated  number  of  employees 
to  be  engaged  upon  each  story,  or  separated  subdivision  of  any 
story,  must  be  approved  before  occupancy. 

For  buildings  over  two  stories  high,  all  staipways  and  elevator 
shafts  to  be  enclosed  with  fire-resisting  walls,  and  to  have  fire- 
resisting  doors.  Stairs  to  be  of  fire-resisting  construction,  and 
floors,  walls  and  partitions  to  be  fire-stopped  where  required. 

For  fire  escapes,  stairs  to  be  not  steeper  than  45  degrees, 
balconies  not  less  than  4  ft.  wide  when  one  above  the  other,  or 
3  ft.  wide  when  of  'straight  run'  plan;  entrance  doors  to  be  at 
floor  level,  doors  or  windows  opening  onto  or  under  a  fire  escape 
to  be  metal  covered  and  wire  glass;  cantilever  ladders  to  connect 
to  ground. 

The  estimated  number  of  persons  liable  to  use  stairways  and 
fire  escapes  must  not  be  exceeded  (see  "Fire  Escapes,"  page  534). 

Roof  stairs  to  be  furnished  for  all  buildings  not  detached. 

Doors  leading  to  fire  escapes  to  have  designated  signs. 

Pails  of  water  and  sand  to  be  provided  and  located  as  directed. 

In  the  absence  of  as  good  or  better  local  regulations,  the 
requirements  given  above  should  be  complied  with  in  every 
factory  or  mill  building  over  two  stories  in  height,  at  least  in 
general  interpretation  if  not  in  exact  letter,  in  addition  to  which 
special  care  must  be  exercised  to  keep  aisles  or  passageways 
between  machines,  tables,  stock  or  other  floor  encumbrances,  free 
and  wide  enough  to  permit  safe  exit  in  time  of  need. 

Fire  Alarm  System.  —  The  previously  mentioned  New  Jer- 
sey factory  law  requires  a  suitable  fire  alarm  system  in  all  factory 
buildings  more  than  two  stories  in  height.  This  requirement  is 
so  reasonable  from  the  standpoint  of  safety  of  employees  that  its 
adoption  should  be  universal. 

Factory  buildings  more  than  two  stories  in  height  shall  be 
equipped  with  a  system  of  fire  alarm,  with  sufficiently  large  gon^s, 
located  on  each  floor,  or  within  each  separate  room,  where  more 
than  one  factory  is  located  on  a  single  floor. 

The  system  shall  be  so  installed  as  to  permit  the  sounding 
of  all  the  alarm  gongs  within  a  single  building  whenever  the  alarm 
is  sounded  in  any  one  portion  thereof.  The  means  of  sound- 
ing these  alarms  shall  be  placed  within  easy  access  of  all  the 


FACTORIES  813 

operatives  within  the  specified  factory  or  room,  and  shall  be  plainly 
labeled.  This  system  of  fire  alarms  is  not  to  be  used  for  any 
purpose  other  than  in  case  of  a  fire  or  fire  drill,  and  it  shall  be  the 
duty  of  the  person  in  charge  of  any  factory  or  section  of  a  factory 
wherein  a  fire  originates  immediately  to  cause  an  alarm  to  be 
sounded. 

A  most  excellent  fire  alarm  system  with  auxiliary  connection 
to  fire  department  headquarters  is  described  in  Chapter  XXIII, 
page  752. 

Fire  Drills.  —  The  practice  of  instituting  fire  drills  in  mills 
and  factories  is  sometimes  required  by  law,  as  in  the  New  Jersey 
factory  law  before  quoted,  which  requires  such  drills  at  least  once 
a  month  in  factories  more  than  two  stories  high;  but  oftener  the 
drill  is  voluntarily  adopted  by  factory  owners  or  managers  as  a 
means  of  promoting  the  safety  of  employees.  For  a  more  de- 
tailed description  of  fire  drills,  see  Chapter  XXXVII. 

Occasional  drills  with  fire  protection  apparatus,  whereby  some 
specially  designated  employees  are  regularly  instructed  in  the 
maintenance  and  proper  use  of  extinguishing  appliances,  are  also 
of  great  value. 


CHAPTER  XXVI. 
GARAGES. 

Fire  Hazards.  —  The  fire  hazards  in  garages  result  from  two 
principal  causes,  first,  the  hazards  incident  to  automobiles,  and 
second,  the  hazards  incident  to  the  storage  and  handling  of  gas- 
olene and  other  oils. 

Automobiles,*  if  of  the  gasolene  type,  may  cause  fire  from  igni- 
tion sparks,  or  from  a  back-fire  or  muffler  explosion  due  to  stag- 
nant gasolene  vapor  or  gas;  or,  if  of  the  electric  type,  by  the 
arcing  of  a  switch  at  the  charging  board,  or  by  a  spark  from  an 
unprotected  controller. 

Garage  Fires.  —  A  summary  of  the  causes  of  126  garage  fires 
recorded  by  the  National  Fire  Protection  Association  f  is  as 
follows : 


Special  hazard  causes. 

No.  of 

fires. 

Per  cent,  of 
whole. 

Gasolene  or  benzine  cleaning  
Repairing      

14 
6 

15.6 
6.7 

Filling  gasolene  supply  tanks  
Carbureter  fires  

12 
9 

13.3 
10.0 

Gasolene  fires                                                          

17 

18.9 

Automobile  fires,  cause  unknown,  in  gasolene  automo- 
biles   
Electric  automobile  fires  
Tire  vulcanizing  

8 
2 
3 

8.9 
2.2 
3.3 

Total 

71 

Common  causes                                                       ... 

19 

21 

Special  hazard  causes              

71 

79 

Total                        

90 

Incendiary 

1 

Exposure  
Cause  unknown  fires 

2 
33 

Total  automobile  garage  fires 

126 

*  For  discussion  as  to  fire  hazards  in  automobiles,  see  "The  Automobile  as 
a  Fire  Hazard,"  National  Fire  Protection  Association's  "Quarterly,"  June,  1911. 
t  See  "Quarterly,"  June,  1911. 

814 


GARAGES 


815 


Common  Causes. 

No.  of 
fires. 

Per  cent,  of 
whole. 

Lighting 

1 

1  1 

Heating    

4 

4.4 

Power 

0 

0 

Boiler  (or  fuel  ^  

0 

.0 

Rubbish  (or  sweeoings)                     

3 

3  3 

Oily  material  

6 

6.7 

Smoking  
Lightning 

4 
0 

4.4 
0 

Locomotive  soarks       

0 

.0 

Miscellaneous                                      .       .           

1 

1  1 

Total       

19 

In  all  the  five  boroughs  of  Greater  New  York  there  are  now 
about  two  thousand  garages,  private  and  public,  and  inspectors 
of  the  Bureau  of  Combustibles  recently  discovered  in  them  nine 
hundred  and  seventy  violations  of  the  regulations  governing  their 
operation  —  in  some  instances  a  dozen  or  more  violations  in  one 
establishment;  cases  of  greasy  floors,  open  containers  of  gasolene, 
open  furnaces  and  forges,  and  defective  electric  wiring.  The 
wonder  is  that  under  such  conditions  many  disastrous  fires  have 
not  already  resulted  in  New  York  from  garage  practices  —  and 
especially  when  it  is  considered  that  the  recent  shocking  fire 
tragedy  at  Nantucket  was  caused  by  the  careless  combination 
of  a  burning  match  and  a  recently  oiled  floor. 

Public  Garages,  according  to  the  revisions  of  the  Building 
Code  recommended  by  the  National  Board  of  Fire  Underwriters, 
include  those  buildings  or  portions  thereof  in  which  are  housed, 
for  rent,  care,  demonstration,  storage  or  sale,  more  than  three 
self-propelled  vehicles  or  other  wheeled  machines  using,  or  con- 
taining in  the  tanks  thereof,  volatile  inflammable  fluid  for  fuel 
or  power,  also  all  adjoining  structures  or  buildings  not  cut  off  by 
an  unpierped  fire  wall.  Furthermore, 

No  garage  shall  be  allowed  or  kept  in  any  building  used  in 
whole  or  in  part  for  a  school,  or  place  of  assembly  or  detention, 
hotel  or  apartment,  tenement  or  lodging  house,  or  dangerously 
exposing  any  of  them.  Any  building  erected  or  remodeled  as  a 
garage  and  occupied  in  part  as  an  office  building,  manufacturing 
establishment,  warehouse  or  store  shall  have  such  parts  entirely 
cut  off  from  the  portion  used  as  a  garage  by  unpierced  fire  walls 
at  least  12  inches  thick  and  floors  of  the  equivalent  construction, 
and  shall  be  provided  with  adequate  means  of  exit  independent 
of  that  used  for  the  garage.  All  windows  of  such  portions  thus 
occupied,  located  above  parts  used  as  a  garage,  shall  be  provided 
with  wire  glass  windows  in  metal  frames. 


816         FIRE   PREVENTION   AND   FIRE   PROTECTION 

It  is  questionable  whether  even  the  above  restrictions  as  to 
occupancy  are  stringent  enough.  The  special  hazards  incident 
to  garages  should  be  definitely  considered  in  both  design  and 
construction,  and  occupancy  of  this  character  might  well  be 
limited  to  buildings  especially  constructed  therefor,  and  without 
other  tenantry. 

The  question  of  allowing  basements,  especially  if  used  for  the 
storage  of  automobiles,  is  still  a  mooted  question.  Some  authori- 
ties claim  that  such  use  should  be  permitted,  especially  if  the 
basement  is  adequately  ventilated,  but  the  St.  Louis  ordinance  — 
as  quoted  on  page  821  —  prohibits  basements  except  for  use  as 
boiler  rooms,  while  the  National  Code  prohibits  all  "rooms  or 
open  or  closed  spaces  of  any  character,  except  such  clearance 
.-p;u-e  as  may  be  necessary  for  elevators,"  below  the  street  level. 

Essentials  of  Design  and  Construction.  - 

The  Design  of  public  garages  should  especially  care  for: 

1.  The  isolation  by  means  of  fire-resisting  walls  of  all  boiler 
rooms  and  forge-  or  repair-shops  containing  open  fires  or  lights. 
Access  to  such  rooms  should  preferably  be  provided  by  means 
of  separate  entrances  from  the  outride  of  building. 

2.  The,  isolation  of  each  and  every  floor  by  means  of  efficient 
fire-resisting  enclosures  for  all  vertical  openings. 

'.».  Efficient  ventilation  and  thorough  drainage,  including  well- 
ventilated  settling  chambers  to  prevent  the  accumulation  of 
volatile  oils  and  inflammable  supplies. 

4.  The  installation  of  approved  storage  tanks. 

5.  Provision  for  dispensing  fuel  and  oils  in  the  open  air,  or  at 
in  an  isolated  court  or  passages  where  thorough  ventilation 

may  be  had  at  about  the  ground  line. 
Construction  should  include: 

1.  Thorough    fire-resisting    construction,    especially   masonry 
division  walls,  and  fire-resisting  doors,  and 

2.  Non-absorbent  floors. 

Heating,  Lighting  and  Fires. —  The  heating  of  garages 
should  be  by  means  of  steam  or  hot  water,  and  all  boilers,  etc., 
should  be  located  in  a  room  or  rooms  cut  off  from  the  balance  of 
building  by  means  of  unpierce.d  fire  walls  at  least  S  ins.  thick. 

Forges  or  other  exposed  fires,  lights  or  spark-emitting 
device  or  machine,  and  all  repair  shops,  if  on  or  below  the  top- 
most floor  where  volatile  inflammable  fluids  are  present,  must  be 


GARAGES  817 

in  a  fireproof  room,  with  all  doors  and  openings  between  such 
rooms  and  other  parts  of  the  garage  provided  with  standard  auto- 
matic closing  fire  doors  kept  closed.  All  such  rooms  must  be 
ventilated  at  floor  line. § 

Only  electric  lights  should  be  permitted  as  a  means  of  lighting. 

Filling  of  Tanks  on  Machines.  — 

Section  22.  —  The  supply  tanks  attached  to  or  belonging  to 
vehicles  or  wheeled  machines  must  be  filled  direct  from  the  stor- 
age tank  through  metallic  hose;  or  approved  closed  wheeled 
metallic  tanks  or  buggies,  not  exceeding  in  capacity  sixty  (60) 
gallons  and  provided  with  pump  drawing  from  the  top  of  such 
container,  may  be  used  for  transferring  from  storage  tanks  to 
the  vehicle  tank.  No  soft  rubber  hose  or  siphons  will  be  allowed 
for  drawing  off  or  conducting  such  fluids.  No  open  top  or  splash- 
ing or  wasting  pumps  shall  be  used  and  every  precaution  shall  be 
taken  to  prevent  or  reduce  evaporation  of  such  fluids;  rubber 
tired  wheels  only  shall  be  used  on  portable  tanks.  Not  more  than 
one  such  wheeled  tank  or  buggy  shall  be  allowed  in  any  garage 
except  by  special  written  permission  of  the  Fire  Marshal,  and  no 
other  container  shall  be  permitted  in  any  garage  except  that  the 
use  of  one  metallic  automatic  closing  can  not  exceeding  five 
gallons  in  capacity  may  be  allowed  in  private  garage  by  special 
permission  of  the  Fire  Marshal. § 

Electric  Charging.  —  Where  electric  charging  is  employed,  all 
apparatus  in  connection  therewith,  save  the  wires  leading  to  the 
automobile,  should  be  placed  in  a  room  or  compartment  cut  off 
by  means  of  fire-resisting  walls  and  doors. 

Storage  Tanks,  Piping,  etc.  — 

tin-lion  f>.  —  The  amount  of  such  volatile  inflammable  fluid 
permitted  to  be  kept  for  sale  or  use  shall  be  as  given  in  Table 
No.  1  attached,  except,  that  within  the  fire  limits,  as  now  or  here- 
after adopted  by  ordinance,  no  storage  above  ground  in  excess 
of  five  (5)  gallons  shall  be  permitted,  other  than  in  metallic  wheel 
buggies  in  garages  as  given  in  Section  22. 

Except  as  specified  in  Section  6,  all  reserve  and  storage 
stocks  of  such  volatile  inflammable  fluids  shall  be  kept  in  tanks. 

Tanks.  —  All  tanks  shall  be  of  steel  or  wrought-iron,  not 
less  than  ^,-inch  thick  and  riveted,  and  shall  be  soldered  or 
caulked  or  otheiwise  made  tight  in  a  mechanical  and  workman- 
like manner,  and  shall  safely  sustain  a  hydrostatic  test  of  100 
pounds  per  square*  inch.  They  shall  be  covered  with  asphaltum 
or  other  approved  non-rusting  paint  or  coating.  All  pipe  con- 
nections shall  be  threaded  into  or  through  flanges  or  reinforced 
metal  securely  riveted  or  bolted  to  tank  and  made  tight  without 
gaskets. 

§  This  and  similarly  marked  quotations  in  this  chapter  are  taken  from  the 
1911  Revisions  of  the  Building  Code  of  the  National  Board  of  Fire  Underwriters. 


818         FIRE   PREVENTION   AND   FIRE   PROTECTION 

Tanks  to  be  in  a  location  satisfactory  to  the  Fire  Marshal 
and  may  be  permitted  underneath  a  building  if  located  two  feet 
below  the  basement  floor. 

If  buried  underground,  top  of  tank  must  be  at  least  two 
feet  below  the  surface,  and  be  below  the  level  of  the  lowest  pipe 
in  the  building  used  in  connection  with  the  apparatus. 

If  underneath  or  within  5  feet  of  any  building,  tank  must 
be  enclosed  on  all  sides  by  at  least  12  inches  of  concrete,  and  if 
within  10  feet  of  any  building,  and  not  below  the  lowest  level  of 
any  floor  within  such  building,  it  must  be  enclosed  by  at  least 
6  inches  of  concrete.  No  air  space  shall  be  allowed  immediately 
outside  of  such  tank.  All  connections  from  tank  to  any  house 
or  sub-surface  drainage  system  shall  be  so  arranged  as  to  prevent 
the  flow  of  volatile  or  inflammable  liquid  to  any  such  system  or 
the  leakage  of  any  inflammable  gases  from  such  liquid,  or  prop- 
erly constructed  oil-collectors  shall  be  provided  in  such  connec- 
tion. 

Tanks,  when  above  ground,  must  be  set  on  substantial 
foundations,  and  each  must  be  surrounded  by  a  substantial  earth, 
brick  or  concrete  wall  or  levee,  of  such  height  as  to  contain  1J 
times  the  full  contents  of  such  tank,  and  of  dimensions  and 
strength  satisfactory  to  the  Fire  Marshal.  Such  reservoir  shall 
be  fluid-tight,  kept  in  good  condition  and  not  provided  with 
outlet  or  drain  pipes,  and  shall  be  roofed  and  otherwise  enclosed 
and  ventilated,  if  within  10  feet  of  any  thoroughfare  or  of  any 
opening  in  any  building. 

Each  tank  may  have  a  test  well  passing  unbroken  to  bot- 
tom, and  its  top  end  shall  be  kept  closed  and  locked  except  when 
necessarily  open. 

Piping.  —  All  piping  shall  drain  to  tanks  without  any  traps 
or  pockets  and  shall  be  protected  against  frost  and  mechanical 
injury.  Each  tank  shall  have  a  separate  filling  pipe;  its  filling 
end  shall  be  carried  to  an  approved  point  outside  of  any  building, 
but  not  within  5  feet  of  any  entrance  door,  and  shall  be  set  in  an 
approved  metal  box  with  cover  which  shall  be  kept  locked  except 
during  filling  operations;  this  filling  pipe  shall  be  closed  by  a  cap. 
A  30  X  30  mesh  brass  strainer  shall  be  placed  in  the  supply  and 
tank  ends  of  filling  pipe. 

All  storage  systems  in  which  the  tank  may  contain  in- 
flammable gases  shall  have  at  least  a  1-inch  vent  pipe,  run  from 
top  of  tank  to  a  point  acceptable  to  the  Fire  Marshal,  but  which 
shall  be  at  least  20  feet  above  point  of  filling  and  in  an  inacces- 
sible location  remote  from  fire  escapes  and  never  nearer  than 
3  feet,  measured  horizontally  and  vertically,  from  any  window 
or  other  opening.  The  tank  vent  pipe  shall  terminate  in  a  tee, 
each  end  being  provided  with  a  face-down  bend  and  protected 
by  a  30-mesh  brass  wire  screen.  Provided  that  the  vent  pipe 
may  be  eliminated  and  a  combined  vent  and  filling  pipe,  so 
equipped  and  located  as  to  vent  the  tank  at  all  times,  even  during 
filling  operations,  may  be  used,  if  located  at  least  10  feet  from  any 
building  and  any  thoroughfare.  The  vent  pipe  from  two  or  more 


GARAGES  819 

tanks  may  be  connected  to  one  upright,  provided  they  be  con- 
nected at  a  point  at  least  1  foot  above  supply  filling  level. 

All  pipes  used  in  the  installation  of  such  tanks  and  systems 
shall  be  of  at  least  standard  weight,  galvanized  iron,  with  suit- 
able brass  or  galvanized  iron  fittings.  No  rubber  or  other  pack- 
ings, flanges,  " rights  and  lefts"  or  " running  threads"  shall  be 
used.  If  unions  are  used,  at  least  one  face  must  be  of  brass,  with 
close  fitting  conical  joints.  Litharge  and  glycerine  only  shall  be 
used  on  pipe  joints. 

All  piping  normally  containing  volatile  inflammable  fluid, 
or  which  may  contain  such  fluid  by  any  derangement  of  the  sys- 
tem, shall,  where  passing  through  basements,  passageways, 
storerooms  and  other  places  where  they  are  liable  to  mechanical 
injury,  be  enclosed  in  masonry  at  least  4  inches  thick. 

None  of  the  installation  shall  be  covered  from  sight  until 
after  an  inspection  by  the  Fire  Marshal  and  his  written  approval 
has  been  given. 

All  pipe  connections  shall  be  provided  with  30  X  30  mesh 
brass  wire  screens  at  or  near  junction  with  shell  of  tank  and  also 
close  to  their  outer  ends,  and,  excepting  vents,  all  pipes  in  storage 
system  where  tanks  may  contain  a  mixture  of  inflammable  gases 
and  air  shall  descend  to  near  inside  bottom  of  tank. 

Section  6.  —  The  storage  and  handling  of  volatile  inflam- 
mable fluids  in  cans  or  barrels  in  excess  of  5  gallons  shall  be  inside 
of  buildings  detached  at  least  10  feet  (see  Table),  the  walls  of 
which  shall  be  impervious  to  liquids  and  shall  be  of  solid  masonry 
not  less  than  12  inches  thick  of  more  than  16  feet  high  in  one 
story  with  a  4-foot  parapet,  and  without  wall  openings  within 
3  feet  from  the  floor,  thus  forming  a  reservoir  section.  The  walls 
of  this  reservoir  section  and  their  supports  shall  be  at  least  4 
inches  thicker  than  the  walls  above  them;  they  shall  be  laid  in 
cement  mortar,  the  floor  to  be  of  equivalent  construction.  There 
shall  be  no  openings  of  any  character  from  this  section  nor  con- 
nections to  any  public  sewer  or  drain  or  water  course. 

The  reservoir  section  shall  have  a  holding  capacity,  meas- 
ured from  the  line  1  foot  below  its  lowest  wall  opening,  equal  to 
the  maximum  quantity  of  such  fluids  to  be  stored  or  kept  in  the 
building. 

Incombustible  materials  only  shall  be  used  in  the  construc- 
tion and  outfitting  of  such  buildings.  Windows  shall  have  wire 
glass,  and  in  addition  shall  have  fire  shutters  if  within  50  feet  of 
adjoining  structures. 

No  such  building  shall  be  occupied  for  any  purpose  other 
than  the  storage  and  handling  of  oils  or  other  inflammable  fluids 
and  their  appurtenances.  No  exposed  flame  or  fire  shall  be 
allowed  within  such  building.  No  smoking  shall  be  allowed  on 
the  premises.§ 


820 


FIRE    PREVENTION    AND    FIRE   PROTECTION 


MAXIMUM  AMOUNTS  OF  VOLATILE  INFLAMMABLE  FLUIDS 
ALLOWED  TO  BE  SEPARATELY  STORED  OUTSIDE  THE  FIRE 
LIMITS,  ACCORDING  TO  DISTANCE  FROM  OTHER  STRUC- 
TURES. 


Distance  from  other  buildings  or  struc- 
tures. 

Number  of  gallons  allowed  stored. 

Not  wholly 
in  tanks.* 

In  tanks  but 
not  wholly 
under 
ground.  f 

Wholly  in 
under- 
ground 
tanks,  f 

Under  10  feet  

20  feet  . 
30     ' 
50     ' 
75     ' 

100     ' 
150     ' 

100 
500 
2,000 
5,000 
10,000 
15,000 
20,000 
Unlimited 

300 
1,500 
6,000 
15,000 
50,000 
150,000 
Unlimited 

1,500 
5,000 
20,000 
50,000 
Unlimited 

Over    10  feet  and  not  exceeding 
20 
30 
50 
75 
100 
150          

See  Section  6. 


t  See  Section  5. 


Ventilation.  — 

Section  25.  —  All  garages  shall  have  air  inlets  near  the  top 
of  the  room  each  of  at  least  50  square  inches  area,  provided  with 
screens.  Rooms  containing  volatile  inflammable  fluid  shall  have 
ventilation  openings  of  at  least  30  square  inches,  at  intervals  of 
not  more  than  10  feet  along  all  walls  and  at  floor  level.  These 
openings  shall  connect  by  incombustible  flues  to  the  outside  air 
at  a  point  not  closer  than  3  feet  to  any  window  or  door  opening, 
or  10  feet  of  any  thoroughfare.  They  shall  be  provided  with 
30  X  30  mesh  brass  wire  screen  on  the  inside  of  the  wall  and, 
unless  laid  with  a  downward  slant  direct  to  the  outside  air,  they 
shall  conduct  to  and  through  a  sparkless  fan,  to  be  run  during 
hours  of  operation  and  which  shall  be  of  sufficient  size  to  com- 
pletely change  the  air  volume  every  10  minutes.  Discharge 
outlets  of  vent  pipes  shall  be  provided  with  30  X  30  mesh  brass 
wire  screens.  At  least  one  such  opening  shall  be  at  floor  level 
near  pump.  No  drip  pans  or  return  drips  to  pumps  will  be 
allowed.§ 

Sewer  Connections  Prohibited.  —  Gasolene  is  the  only 
liquid  in  common  use  whose  vapor,  when  mixed  with  air,  is  both 
explosive  and  heavier  than  air.  Gasolene  vapor  will  seek  a  low 
level  almost  as  readily  as  water,  and  hence  tends  to  collect  in  such 
places  as  basements,  drains,  etc.,  where  but  a  moderate  accumu- 
lation is  necessary  to  produce  a  highly  explosive  condition.  All 
connections  between  drains,  etc.,  and  sewers  should,  therefore, 
be  both  vented  and  intercepted,  as  follows: 

Section  29.  —  There  shall  be  no  direct  connection  between 
any  garage  waste  basin,  sink,  floor  drain  or  waste  and  any  house 


GARAGES  821 

drainage  or  sewer  system.  All  such  drains  or  waste  mains  to 
sewer  system  shall  have  intercepting  grease,  oil  and  inflammable 
liquid  traps  or  separators  which  will  completely  separate  such 
substance  from  water  and  sewage  and  allow  of  their  safe  and 
convenient  removal.  Such  traps  shall  be  ventilated  in  the  same 
way  as  is  required  for  oil  tanks.  Grease,  oil,  etc.,  removed  from 
such  traps  or  separators  shall  be  removed  and  disposed  of  to  the 
satisfaction  of  the  Fire  Marshal.  § 

Construction.  —  The  Revisions  of  the  Building  Code  of  the 
National  Board  of  Fire  Underwriters  require  all  public  garages 
to  be  of  fire-resisting  construction,  and  "all  trim  or  other  interior 
finish  to  be  of  metal  or  wood  covered  with  metal,  or  of  other  non- 
flammable approved  material." 

One  of  the  most  stringent  municipal  garage  ordinances  so  far 
enacted  and  enforced  by  any  American  city  is  that  of  St.  Louis, 
which  requires  public  garages,  i.e.,  those  containing  five  or  more 
automobiles,  to  conform  to  the  following: 

Section  3.  —  No  building  exceeding  one  story  in  height  shall 
be  used  as  a  garage  within  the  city  of  St.  Louis  unless  such 
building  be  a  building  of  the  first  class,  and  no  building  used  for 
a  garage  shall  have  a  basement  except  of  such  dimensions  and 
size  as  shall  be  approved  by  the  Commissioner  of  Public  Build- 
ings, and  said  basement  shall  be  used  only  for  a  boiler  room  for 
the  purpose  of  heating  the  building,  and  shall  not  be  used  for 
repair  shop  purposes  or  the  storage  of  automobiles  or  the  storage 
of  any  volatile  inflammable  liquid.  No  building  shall  be  used 
as  a  garage  within  the  city  of  St.  Louis  unless  the  floor  on  which 
automobiles  containing  volatile  inflammable  liquids  are  stored 
shall  be  of  concrete  or  granitoid,  providing,  however,  that  the 
provisions  of  this  section  shall  not  apply  to  buildings  occupied 
for  garage  purposes  at  the  time  of  the  passage  of  this  ordinance. 

Types  of  fire^resisting  construction  have  been  sufficiently 
covered  in  former  chapters,  but  a  few  points  particularly  appli- 
cable to  garages  require  brief  mention. 

Floors  should  be  thoroughly  fire-resisting  and,  unless  of  earth, 
should  be  of  such  finish  or  surface  as  will  not  readily  absorb  oil. 
From  this  standpoint,  stone  floors  are  undoubtedly  best  for 
garages,  but  as  the  cost  of  such  floors  will  generally  preclude  their 
use,  granolithic  may  be  substituted  when  given  an  oil-proof 
coating.  Several  preparations  to  render  cement  floors  oil-proof 
are  now  on  the  market. 

Elevators,  Stairways  and  Doors.  — 

All  elevators  and  stairways  in  garages  shall  be  enclosed  with 
fireproof  materials  and  shall  conform  to  the  requirements  of 


822         FIRE    PREVENTION   AND    FIRE    PROTECTION 

Section  97  of  the  Building  Code,  except  that  no  window  open- 
ings from  shafts  to  within  the  building  shall  be  permitted  in  any 
said  enclosing  walls  or  construction,  and  no  glass  panel  or  window 
shall  be  permitted  in  any  door  opening  from  shafts  into  the  build- 
ing. All  inter-connecting  openings,  passageways,  stair  or  eleva- 
tors shall  be  protected  with  automatic  fire  doors  arranged  to  open 
or  close  from  either  side.  All  fire  doors  and  shutters  shall  be 
constructed  and  installed  as  given  in  Section  105  of  the  Building 
Code,  except  as  above  restricted,  and  all  such  doors  shall  overlap 
these  openings  at  least  four  inches  on  each  side  and  the  top.§ 


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GARAGES  823 

Elevator  Doors,  Etc.  —  The  installation  of  elevator  doors  for 
such  buildings  as  garages,  carriage  factories,  etc.,  where  wide  and 
high  door  openings  must  be  secured  for  loading  freight  elevators, 
is  often  perplexing.  For  such  openings  swing  doors  are  too  large 
and  heavy,  and  occupy  too  much  floor  room  and  clearance  in 
opening,  while  slide  doors  are  seldom  possible  on  account  of  lack 
of  wall  space.  A  very  satisfactory  arrangement  for  such  in- 
stallations is  found  in  the 

"Peelle"  Doors,  which  consist  of  counterbalanced  tin-covered 
doors,  bolted  into  steel  frames,  hung  with  ball-bearing  pulleys, 
and  operated  in  anti-friction  tracks.  The  appearance  of  these 
doors,  slightly  ajar,  viewed  from  the  elevator  side,  is  shown  in 
Fig.  350.  The  method  of  connecting  the  two  halves  of  each  open- 
ing, so  that  they  will  move  simultaneously  in  opposite  directions, 
is  indicated.  Two  methods  of  operation  are  shown  in  Fig.  351. 
That  on  the  right-hand  side  of  well  room  is  suited  to  story  heights 
where  panels  one-half  as  high  as  the  required  door  opening  may 
be  opened  to  occupy  the  space  between  the  head  of  door  and 
floor.  That  on  the  left-hand  side  of  well  room  shows  how  the 
doors  may  be  made  to  lap  by  each  other  where  the  story  heights 
are  not  sufficient  to  give  enough  room  over  heads  of  openings. 
In  this  case,  automatic  movable  lintels  are  placed  at  the  heads 
of  openings  to  close  up  the  spaces  between  the  lintels  and  inner 
doors. 

"Turn  Over"  Doors.  —  A  new  type  of  fire  door,  especially 
intended  for  garages,  entrances  to  warehouses,  shipping  platforms, 
etc.,  is  illustrated  at  the  lower  right-hand  side  of  Fig.  351.  The 
peculiar  feature  regarding  these  doors  is  the  manner  in  which 
they  are  stowed  away  at  the  ceiling,  when  open.  This  makes  it 
possible,  as  at  shipping  platforms,  etc.,  to  install  a  number  of  such 
doors  side  by  side  without  taking  up  floor  space.  The  doors, 
which  are  tin-covered  wood,  have  side  rollers  which  run  in  tracks 
or  guides  attached  to  the  jambs  and  to  the  ceiling.  A  hand 
chain-hoist  operates  conical  spiral  wheels  which  serve  to  equalize 
the  counter  weighting  in  the  varied  positions  of  the  doors. 

Sand  and  Deterrents.  — 

Section  27.  —  Dry  sand,  ashes  and  other  fire  deterrents 
shall  be  provided  in  such  quantities  and  be  located  with  pails, 
scoops  and  other  fire  appliances  as  may  be  directed  by  the  Fire 
Marshal.  A  reasonable  quantity  of  loose,  non-combustible 
absorbents  shall  be  kept  convenient  for  use  in  case  of  excessive 
oil  waste  or  overflow. § 


824         FIRE   PREVENTION   AND   FIRE    PROTECTION 


n 

< 
< 

W 
5 
4 

i 

i, 

r 

/Movable 
Lintel 

^ 

I 

"PEELLE" 

( 

T- 

9 

3 
4 

DOORS  'CLOSED 

2nd  Floor 

I 

Li 

1 

M 

1 

^ 

2nd  Floor  Line 

^ 

C 

$ 
i 

1 

111 

Pea 

IT 

JN^^SIIII^ 

il 

i^~                                           "^ 

1 

o 

Sk 

1  p 

o 

^'PEELLE" 

fTurn. 

DOORS  OPEN 

Over" 
Doors 

Poors  bound 
on  edge  to  permit 

1st  Floor 

Line 
r.  H^ 

trucking  over 

\ 

Floor  Line 

W7^Mi 

ii 

l 

tg^^=  —  »  —  ~^~--'    —  j  —  ^-    '•  j-  —  =•  -^.  —  ~p=  — 

1 

mm 

Elevator 

1 

FIG.  351.  —  Operation  of  "Peelle"  and  "Turn  Over"  Doors. 

See,  also,  paragraph  "Fire  Tests  with  Liquid  Petroleum 
Products,"  Chapter  XXXII,  page  934. 
Care  of  Premises.  — 

All  garages  should  be  kept  clean  and  without  litter.  Grease, 
oil-  or  paint-soaked  rags,  waste  or  other  combustible  materials 
of  like  character  should  be  kept  in  self-closing  ventilated  metallic 
receptacles  having  metallic  legs  at  least  3  inches  high  and  securely 


GARAGES  825 

braced.  These  receptacles  should  be  kept  safely  clear  of  all 
combustiblp  surroundings  and  their  contents  should  be  safely 
disposed  of  at  least  once  each  day.  Oiled  and  greased  clothing 
should  be  cared  for  in  non-combustible  and  well  vented  closets 
safely  located. § 

Smoking  in  garages  should  be  made  a  misdemeanor,  and  signs 
to  this  effect  should  be  conspicuously  posted  on  the  premises. 
Private  Garages.  — 

Section  19.  —  All  automobile  garages  or  shelters  housing 
not  more  than  three  motor  vehicles  shall  be  known  as  private 
garages,  and  if  located  not  closer  than  20  feet  to  any  other  build- 
ing may  be  of  non-fireproof  construction,  but  must  have  walls 
of  masonry;  provided,  that  if  any  portion  of  such  building  is  used 
as  a  dwelling,  the  portions  so  used  must  be  entirely  cut  off  from 
the  remainder  of  the  building  by  unpierced  fireproof  floors  and 
partitions,  and  provided  further,  that  shelters  or  garages  in  resi- 
dential districts  with  capacity  for  only  one  automobile  may  be 
of  frame  or  metal-clad  construction.  § 

Types  of  Construction,*  other  than  wood,  include  brick  or 
stone,  hollow  tile  and  stucco,  reinforced  concrete,  concrete  blocks, 
concrete  tile  and  stucco,  gas-pipe  frame  with  wire-  or  metal-lath 
and  stucco,  and  uHy-Rib"  and  stucco.  All  of  these  construc- 
tions save  the  latter  two  have  been  sufficiently  described  in 
previous  chapters. 

Pipe-frame  and  Stucco.  —  This  simple  and  economical  method 
of  securing  a  fire-resisting  construction  for  a  small  garage  consists 
of  a  brick  or  concrete  footing  course  upon  which  is  built  a  frame- 
work consisting  of  2|-in.  galvanized-iron  pipe  uprights  spaced 
not  over  5  ft.  centers,  to  which,  by  means  of  pipe  fittings,  also 
galvanized,  are  connected  l|-in.  horizontal  pipes  not  over  4  ft. 
centers.  The  uprights  should  be  secured  to  the  footing  course  by 
means  of  threaded  pipe  dowels  which  are  built  in.  After  the  pipe 
framework  is  complete,  including  an  overhanging  roof  frame, 
J-in.  by  i-in.  flat  iron  is  attached  thereto  vertically  —  spaced 
not  over  16  ins.  centers  —  by  bending  the  ends  around  the  pipe, 
or  by  wiring.  Metal-  or  wire-lath  and  three-coat  stucco  work,  — 
two  coats  outside  and  one  coat  inside,  —  with  a  finished  roofing, 
will  complete  the  main  framework. 

"Hy-Rib"  and  Stucco.  —  A  construction  very  similar  to  the 

*  For  descriptions  and  illustrations  of  several  concrete  and  plaster  types,  see 
booklet  "Concrete  Garages"  issued  by  the  Atlas  Portland  Cement  Company. 


826      FIRE   PREVENTION   AND   FIRE   PROTECTION 

above  may  be  made  by  using  a  light  framework  of  2-in.  X  2-in. 
steel  angles  at  all  corners  and  at  door  and  window  jambs,  to 
which  are  connected  horizontal  5-in.  I-beams  at  the  eave  lines. 
Sheets  of  "Hy-Rib"  steel  sheathing  with  stiffening  ribs  are  then 
clipped  on,  including  roof  of  any  desired  shape,  and  stucco  finish 
is  applied  as  before. 


CHAPTER  XXVII. 
SAFES,  VAULTS,   METAL  FURNITURE,   ETC. 

Portable  Safes.  —  Fireproof  safes,  so  called,  are  constructed 
of  two  distinct  types  —  those  having  double  metal  walls  with  an 
intervening  air-space,  and  those  having  double  metal  walls  with 
the  intervening  space  filled  with  cement.  The  latter  type  is 
generally  considered  far  more  fire-resisting  than  the  former, 
owing  to  the  water  of  crystallization  which  is  contained  in  the 
cement.  Under  a  sufficiently  high  temperature  this  water  of 
crystallization  is  released  and  passes,  in  the  form  of  steam,  into 
the  interior  of  the  safe.  No  type  of  dry  cement  or  dry  filling  is 
usually  considered  comparable  to  wet  cement  filling. 

The  following  information  on  the  subject  of  portable  safes  was 
outlined  by  a  committee  of  the  National  Fire  Protection  Associa- 
tion, appointed  to  consider  and  report  on  "  Vaults  and  Safes:"* 

First :  There  is  a  sensible  degree  of  safety  in  having  a  vault 
or  safe  located  on  or  near  the  ground;  in  other  words,  exposure 
to  falls  is  always  attended  by  some  risk. 

Second:  Notwithstanding  the  view  expressed  in  the  pre- 
ceding paragraph,  it  is  a  fact  that  a  well-constructed  safe  will 
usually  stand  a  considerable  fall  without  injury  to  the  contents. 

Third:  The  security  of  a  safe  from  injury  by  falling  is  not 
dependent  on  any  one  or  few  details  of  construction,  such  as  the 
shape  of  the  corner  of  the  door,  or  the  exact  style  of  the  frame  or 
hinges,  but  is  principally  dependent  on  the  general  excellence  of 
the  materials  and  workmanship. 

Fourth:  Full  burglar-proof  and  full  fireproof  properties 
should  not  usually  be  looked  for  in  any  one  construction,  unless 
the  structure  be  a  first-class  ground  level  vault.  If  full  burglar- 
proof  and  full  fireproof  qualities  are  to  be  looked  for  in  a  portable 
safe,  the  combination  of  qualities  should,  in  general,  be  looked  for 
in  a  combination  of  a  burglar-proof  safe  enclosed  within  a  fireproof 
safe. 

Fifth:  In  making  special  contracts  to  insure  the  contents 
of  safes,  underwriters  should  bear  in  mind  that  what  are  called 
light-weight  safes,  or  safes  with  walls  about  four  inches  thick, 
while  reasonably  fireproof  when  used  in  steel  frame  office  build- 

*  See  "Proceedings  of  Eleventh  Annual  Meeting  of  National  Fire  Protection 
Association." 

827 


828         FIRE    PREVENTION    AND    FIRE    PROTECTION 

ings,  are  by  no  means  reasonably  fireproof  when  placed  in  situa- 
tions where  surrounded  by  a  great  mass  of  combustibles. 

Sixth:  The  usefulness  of  cement-filled  safes  is  wholly  de- 
pendent upon  the  quality  of  the  cement.  The  cements  in  general 
are  known  as  wet  and  dry  cements,  it  being  possible  to  produce  a 
first-class  safe  with  either  class  of  cement.  Dry  cement  is  com- 
mercially preferable,  to  save  weight  in  handling  and  shipping 
safes.  Good  dry  cement  is,  however,  less  seldom  met  with  than 
good  wet  cement,  and  both  classes  of  cement  offer  temptation  to 
cheapness  as  against  quality,  thus  making  the  actual  value  of 
fireproof  safes  extremely  dependent  upon  the  commercial  integrity 
and  the  value  of  the  good  will  of  the  manufacturer. 

Heavy  safes  should  never  be  supported  on  wood  stands  or  even 
on  combustible  flooring.  Compare  with  Chapter  XI,  page  334, 
especially  in  regard  to  the  Parker  Building  fire,  and  the  relation 
of  the  weights  of  heavy  safes  to  the  ultimate  floor  capacity. 

Safes  in  Baltimore  Fire.  —  After  the  Baltimore  fire,  the 
contents  of  a  great  many  safes  were  destroyed  by  premature 
opening.  If  a  safe  is  not  thoroughly  cooled  off,  the  opening  of 
the  door  and  the  admission  of  oxygen  produces  combustion 
instantly.  Safes  should  never  be  opened,  after  passing  through 
a  fire,  as  long  as  any  heat  can  be  felt  by  the  hand.  They  should 
be  cooled  by  air  only,  never  by  water,  and  should  not  be  opened 
until  stone  cold.  This  cooling  usually  requires  from  two  to  four 
days. 

The  greatest  losses  to  contents  of  safes  in  the  so-called  fire- 
resisting  buildings  occurred  in  the  Equitable  building,  where  the 
inadequate  floor  construction  allowed  a  large  number  of  safes  to 
fall  through  to  the  basement,  into  debris  which  smouldered  many 
days. 

Portable  safes  made  a  very  poor  showing,  approximately 
sixty-five  per  cent,  of  their  contents  having  been  destroyed.  This 
was  true  of  all  the  various  grades  of  ordinary  safes  with  an  in- 
sulating filler  of  concrete  varying  from  3  to  6  inches  in  thickness.* 

Safes  in  San  Francisco  Fire.  — 

Portable  safes  and  small  vaults  gave  very  unsatisfactory 
results.  In  many  of  the  large  office  buildings,  particularly  those 
of  Class  B  construction  with  wood  floors,  fires  of  sufficient  inten- 
sity occurred  to  incinerate  the  contents  of  the  largest  safes. 
Many  of  these  were  of  standard  makes  and  supposed  to  be  suffi- 
ciently fire-resisting  to  preserve  their  contents,  the  walls  being 
in  many  cases  8  ins.  to  12  ins.  thick  and  filled  with  composition 
non-heat-conducting  materials.  One  of  these  large  safes,  in  the 

^  Report  of  National  Fire  Protection  Association  on  Baltimore  fire. 


SAFES,  VAULTS,  METAL   FURNITURE,  ETC. 


829 


Crossley  building,  became  heated  to  such  a  degree  that  not  only 
were  the  paper  contents  reduced  to  black  ashes,  but  silver  coins 
were  partially  fused,  entire  packages  or  rolls  of  20  silver  dollars 
being  fused  together  into  one  piece. 

In  many  of  the  fireproof  office  buildings,  where  fires  of  much 
less  intensity  and  shorter  duration  occurred,  a  majority  of  the 
better  makes  of  safes  preserved  their  contents  in  a  fairly  satis- 
factory manner.  In  most  of  these,  however,  the  papers  were 
scorched  and  discolored,  and  in  some  cases  destroyed.  There 
were  very  few  instances  where  paper  documents  were  preserved 
without  injury.* 

VAULTS. 

Usual  Inefficient  Construction.  —  In  modern  office  build- 
ings, where  vaults  are  required  on  each  and  every  floor  for 
the  convenience  of  tenants,  they  have  either  been  built  in  all  or 
in  the  principal  offices,  or  else  one  larger  vault  has  been  provided 
on  each  floor  (opening  from  a  corridor),  in  which  a  sufficient 
number  of  vault  boxes  are  placed  to  accommodate  the  tenants  of 
that  floor.  The  usual  construction  of  such  vaults  has  been  in- 
efficient to  a  degree. 


SECTION  OF  CEILING  OF  VAULT 
Tee  Iron  and  Book  Tile  Roof. 


PLAN 


SECTION  OF 

VAULT  DOOR 

JAMB 


SECTION^ 
Through  Vault 

Door  Head  Corridor  Line /Partition 

FIG.  352.  —  Inefficient  Hollow  Tile  Vaults. 

Fig.  352,  which  is  taken  from  a  catalog  published  some  years 
ago  by  a  hollow  tile  fireproofing  company,  was  intended  to  sug- 
gest the  proper  construction  of  office  vaults  built  of  hollow  tile  — 
practically  the  only  material  then  used  for  such  vaults.  This 
illustration  should  have  been  labelled  "How  vaults  should  not  be 
built." 

*  A.  L.  A.  Himmelwright  in  "The  San  Francisco  Earthquake  and  Fire." 


830         FIRE   PREVENTION   AND   FIRE   PROTECTION 

In  the  report  of  the  National  Fire  Protection  Association  on 
the  Baltimore  fire,  the  following  description  is  given  of  the  office 
vaults  in  the  Continental  Trust  Company's  Building. 

Numerous  vaults  carried  on  floor  arches.  Sides  of  5-in. 
hollow  tile,  tops  of  3-in.  hollow  tile  on  T-irons;  double  iron  doors 
with  no  insulation  and  separated  14  inches.  Outer  door  -f-g-m. 
sheet-steel  on  framing  of  2-in.  by  2-in.  by  rVm-  angles.  Inner 
door  iV-in.  sheet-steel  on  framing  of  strap-iron  y^-in.  by  2  inches. 

The  report  adds  that  the  "  contents  of  a  large  number  of  vaults 
on  different  floors  were  destroyed." 

Vaults  constructed  as  illustrated  in  Fig.  352  are  faulty  in 
many  particulars.  The  insulation  against  heat  is  insufficient; 
the  construction  of  the  walls  —  often  merely  partitions  —  is  not 
rigid  enough  to  resist  even  hose-streams,  while  the  roof  or  cover- 
ing is  not  strong  enough  to  withstand  moderate  loads,  to  say 
nothing  of  blows  resulting  from  falling  debris. 

Irrespective  of  any  danger  from  falls,  no  reliance  should  be 
placed  upon  the  office  vaults  found  in  modern  office  buildings 
unless  inspection  shall  show  that  the  individual  vault  is  worthy 
of  a  degree  of  confidence.  This  is  because  many  of  these  so-called 
vaults  are  not  vaults  at  all,  but  are  merely  lock-up  boxes,  made  of 
common  mortar  and  brittle  hollow  tile. 

In  addition  to  the  above  defects,  the  vault  doors  are  commonly 
made  of  too  light  and  too  cheap  construction  to  be  efficient  in  the 
time  of  need  for  which  they  were  placed,  and,  also,  doors  have 
frequently  been  placed  on  top  of  wood  screeds  or  flooring. 

Vaults  in  Baltimore  Fire.  — 

Vaults  made  of  ordinary  terra-cot ta  tile  5  ins.  thick  and 
carried  on  the  floors  and' structural  frame,  failed  in  a  number  of 
cases,  due  to  the  fact  that  the  tile  was  fragile  and  was  cracked  or 
broken  by  the  heat.  About  25  per  cent,  of  the  contents  of  tile 
vaults  were  destroyed.  Some  of  these  tile  vaults  also  had  double 
doors  each  made  of  a  single  thickness  of  sheet-steel  with  no  insula- 
tion against  heat.  In  a  number  of  cases  the  inner  door  had  been 
left  open  and  the  heat  which  radiated  through  the  outer  door 
destroyed  the  contents. 

Vaults  made  of  brick  walls  built  up  from  the  ground,  es- 
pecially those  having  double  walls  with  air-space  between,  made 
a  remarkably  good  showing  when  provided  with  double  iron 
doors,  the  outer  one  being  filled  with  about  4  ins.  of  cement  for 
insulation  against  heat.* 

*  National  Fire  Protection  Association  Committee  Report. 


SAFES,  VAULTS,  METAL    FURNITURE,  ETC.  831 

Vaults  in  San  Francisco  Fire.  — 

In  many  of  the  office  buildings  in  San  Francisco,  suites  of 
offices  were  equipped  with  vaults,  some  of  which  were  fairly 
capacious  and  provided  with  doors  of  more  or  less  efficient  ap- 
pearance, a  number  of  them  having  the  ordinary  vestibule,  with 
both  inner  and  outer  doors.  Where  the  interior  partitions  of 
the  building  consisted  of  metal  furring,  lathing  and  plaster,  the 
walls  of  the  vaults  were  likewise  of  these  materials.  Where  the 
interior  partitions  consisted  of  hollow  tile,  the  walls  of  the  vaults 
were  of  hollow  tile  also.  Although  I  examined  a  great  many,  I 
did  not  see  a  single  vault  partitioned  off  either  with  metal 
lathing  and  plaster  or  with  hollow  tiles  that  preserved  its  con- 
tents. .  .  . 

In  the  Baltimore  fire  there  were  a  number  of  vaults  walled 
off  with  hollow  tiles,  and  all  that  I  happened  to  see  during  my 
inspection  of  the  ruins  in  Baltimore  had  failed.  The  same  thing 
was  in  evidence  everywhere  in  San  Francisco,  and  it  is  my  opinion 
that  this  result  could  have  been  predicted  with  absolute  certainty 
at  the  time  these  vaults  were  built,  from  data  then  available. 
To  all  external  appearances,  no  doubt,  the  vaults  looked  like 
secure  places  in  which  to  keep  valuables;  as  a  matter  of  fact,  they 
were  the  flimsiest  kind  of  shells,  not  capable  of  resisting  any  sort 
of  determined  attack  from  either  fire  or  burglars.  The  tenant 
would  have  been  better  off  without  the  vault,  for  in  that  case  he 
would  probably  have  carried  his  papers  to  some  other  point  where 
they  would  have  had  a  better  chance  to  escape  the  fire. 

The  only  vaults  I  saw  that  came  through  a  really  fierce  fire 
without  damage  were  those  built  of  brickwork.  Even  these 
vaults  did  not  always  protect  their  contents,  however.  I  saw  a 
number  of  them  opened  in  which  the  contents  had  been  totally 
destroyed.  As  they  seemed  to  be  fairly  good  vaults,  this  result 
was  a  matter  of  more  than  ordinary  interest.  I  therefore  care- 
fully examined  a  number  of  them  and  discovered  that  the  fire  had 
gained  access  through  cracks  due  to  settling,  or  to  the  earthquake, 
or  else  through  unfilled  joints,  due  to  poor  workmanship  in  the 
original  construction  of  the  vault.  It  appeared  that  probably 
the  contents  of  the  building  were  burning  fiercely  around  the 
vault  before  the  floor  above  had  burned  out  or  collapsed,  so  as  to 
give  full  vent  to  the  gases  of  combustion.  Some  pressure  must 
have  been  generated  by  the  great  heat  thus  confined,  and  under 
this  pressure  the  incandescent  gases  resulting  from  the  fire  found 
their  way  through  the  smallest  and  most  tortuous  passages  in 
the  brickwork.  In  several  cases  it  was  apparent  that  the  con- 
tents had  probably  been  ignited  by  a  small  tongue  of  flame  (prob- 
ably not  thicker  than  a  lead  pencil)  penetrating  into  the  vault 
as  a  result  of  such  conditions. 

A  few  vaults  failed  owing  to  the  fact  that  the  outer  door 
warped  and  pulled  away  from  the  frame.  Whether  this  warping 
could  have  been  prevented  with  an  adequate  number  of  bolts  I 
do  not  know,  but  in  an  important  vault  it  would  seem  worth  while 
to  have  the  outer  door,  at  least,  filled  in  the  same  manner  as  the 


832         FIRE    PREVENTION    AND    FIRE    PROTECTION 

door  of  a  fireproof  safe.     If  it  were  built  in  this  way  it  would 
probably  not  warp  —  at  least  not  enough  to  let  the  fire  in.* 

Vaults  with  walls  of  cinder  concrete  4  ins.  thick  came  through 
the  San  Francisco  fire  without  damage  to  contents. 

Proper  Construction  of  Vaults.  —  In  the  design  of  vaults 
for  the  preservation  of  valuable  papers,  etc.,  in  office  buildings, 
town  halls,  mercantile  buildings  and  the  like,  great  improve- 
ment is  necessary  over  usual  practice.  Individual  vaults  in 
separate  offices  of  office  buildings  should  be  avoided,  —  unless 
built  in  tiers  as  described  below,  —  and  should  be  replaced  by 
tiers  of  corridor  vaults,  in  which  the  walls  should  start  at  the 
foundations  and  run  continuous  to  the  top  of  the  uppermost  vault. 
Such  walls  should  be  of  brick,  not  less  than  8  or  10  ins.  thick,  tied 
with  corner  irons  at  all  angles,  and  laid  in  good  Portland  cement 
mortar,  all  joints  thoroughly  pointed.  Or,  reinforced  concrete 
walls,  4  ins.  thick,  may  be  used  as  adequate  under  all  ordinary 
conditions.  Compare  with  paragraph  "  Concrete  Spandrel 
Walls,"  Chapter  XX,  page  656.  The  floor  of  each  vault 
(preferably  forming  the  ceiling  of  the  vault  below)  should  be 
independent  from  the  surrounding  floor  areas,  and  should  either 
be  of  especially  heavy  and  deep  hollow  tile  arches,  or  better,  of 
reinforced  concrete  or  brick  arches.  The  roof  of  the  top  vault 
should  be  equal  to  a  floor  in  stability  if  higher  buildings  are 
adjacent.  Finished  floors  of  vaults  should  be  of  cement  or  other 
incombustible  material,  and,  in  order  to  further  protect  the  doors, 
a  threshold  of  cement  or  other  incombustible  flooring  should 
project  at  least  one  foot  into  each  room  in  front  of  the  door. 
Each  tier  of  vaults  should  be  independent,  as  to  stability,  from 
all  other  construction,  and  special  attention  should  be  paid  to 
providing  adequate  foundations,  so  that  no  settlement  may  take 
place. 

If  vaults  are  to  be  used  by  various  tenants,  standard  "  vault 
boxes,"  24  X  24  X  24  inches  in  size,  may  be  installed. 

Vault  Doors.  —  In  many  of  the  older  fire-resisting  buildings, 
lack  of  foresight,  keen  competition,  and  a  too  close  scrutiny  into 
the  first  cost,  led  to  the  installation  of  very  many  cheap  vault 
doors,  unworthy  of  any  reliance  whatever.  Those  previously 
described  as  found  in  the  Continental  Trust  Co.'s  Building  are, 
unfortunately,  only  too  common.  The  experiences  of  Baltimore 
and  San  Francisco,  however,  have  shown  so  conclusively  the  folly 

*  Captain  Sewell,  in  United  States  Geological  Survey  Bulletin  No.  324. 


SAFES,  VAULTS,  METAL   FURNITURE,  ETC.  833 

of  such  economy,  that  a  gradual  improvement  in  the  quality  used 
has  been  taking  place  of  late  years,  until  now  far  better  grades 
of  vault  doors  are  being  made  and  sold  than  have  been  demanded 
in  the  past. 

The  so-called  "standard"  vestibule  door,  made  with  minor 
differences  by  the  various  safe  manufacturers,  but  generally  with 
a  single  iVin.  outer  plate  door,  with  vestibule  and  inner  doors,  is 
wholly  unfit  for  use  except  under  the  very  lightest  hazards.  For 
moderate  hazards,  the  outer  door  should  be  made  of  not  less  than 
|-in.  Bessemer  steel  plate,  while  for  severe  hazards,  a  double 
outer  door  is  essential.  This  may  be  made  of  J-in.  outer  and 
|-in.  inner  Bessemer  steel  plates,  with  an  intervening  air-space, 
or  the  latter  space  may  preferably  be  cement-filled,  or  insulated 
by  non-heat-conducting  material.  The  total  thickness  of  such 
doors  is  1|  ins.  The  bolts  are  then  amply  protected,  and  with 
the  air-space  of  the  vestibule  and  the  added  protection  of  the 
inner  vestibule  doors,  contents  should  be  safe.  Another  good 
point  of  the  double  outer  door  is  that  such  types  are  usually  pro- 
vided with  three  hinges  instead  of  two  as  in  the  cheaper  grades. 

Setting  of  Vault  Doors.  —  Vault  doors  are  not  usually  placed 
in  position  until  the  building  is  nearly  completed.  The  plaster- 
ing should  be  finished,  and  thoroughly  dried  out,  so  that  the 
doors  may  not  be  subjected  to  undue  moisture. 

The  openings  left  in  the  masonry  walls  are  usually  made  one 
inch  wider  and  one-half  inch  higher  than  the  outside  dimensions 
of  the  vestibule.  The  inner  flange  or  frame  of  the  vestibule  is 
first  removed,  the  vestibule  and  doors  inserted  in  the  opening, 
and  the  inner  flange  replaced.  Before  the  latter  operation,  how- 
ever, great  care  should  be  taken  to  see  that  the  space  between 
the  wall  and  the  vestibule  is  thoroughly  filled  or  grouted.  A 
careless  joint  may  easily  prove  the  ruin  of  the  contents.  In  this 
connection,  the  writer  knows  of  a  case  in  the  Chelsea  conflagra- 
tion where  the  contents  of  the  vault  of  a  banking  institution  in 
that  city  were  completely  destroyed  because  the  vault  door  had 
been  placed  within  a  brick  wall  opening  with  rowlock  or  arched 
head,  and  the  space  between  the  top  of  the  vault  door  and  the 
rowlock  had  been  filled  in  with  wood,  faced  with  plaster. 

Construction  of  Large  Vaults. 

For  vaults  larger  than  the  ordinary  office  building  type,  double 
brick  walls  with  an  air-space,  or  reinforced  concrete  walls  with 


834         FIRE   PREVENTION   AND   FIRE   PROTECTION 

an  air-space,  are  often  used.  For  the  former,  a  20-in.  wall  made 
of  two  walls  of  one  and  a  half  bricks  each  has  been  found  reliable. 
The  air-space  should  be  ventilated  by  providing  vents  from  the 
bottom  of  the  vault  into  the  air-space,  and  from  the  top  of  the 
air-space  into  the  outside  air,  such  inlets  and  outlets  not  to  be 
placed  opposite,  but  as  far  as  possible  from  each  other.  The  tops 
of  such  vaults  are  usually  made  solid,  without  air-space. 

In  considering  the  safety  of  large  or  basement  vaults,  even 
when  all  other  conditions  are  apparently  favorable,  underwriters 
should  ascertain  whether  the  vault  was  originally  built  complete 
as  a  continuous  structure.  This  is  because  vaults  which  are 
merely  composed  of  three  sides,  built  in  the  corner  of  an  old 
building  in  some  instances,  have  no  reliable  bond  between  the 
old  masonry  and  the  new,  and  also  are  liable  to  have  fire  enter 
through  cracks  caused  by  settlement  of  the  original  building. 
In  other  words,  a  complete,  independent  vault  is  the  preferred 
type.* 

If  large  vaults  are  placed  in  first  story  or  basement,  the  strength 
of  the  vault  roof  is  important,  owing  to  the  possible  collapse  of 
the  building,  or  portions  thereof,  above.  If  in  basement  or  sub- 
basement,  the  vault  doors  should  either  be  tested  to  prove  water- 
tight qualities,  or  else  provision  should  be  made  for  carrying  off 
water  due  to  possible  fire  engine  streams,  leakage  or  breakage  of 
water  mains,  etc.  In  the  Equitable  Building  in  New  York  City, 
which  was  destroyed  by  fire  January  9,  1912,  it  was  estimated 
that  the  many  Safe  Deposit  and  private  vaults  located  in  the 
building  contained  securities  and  other  valuables  to  the  amount 
of  approximately  one  billion  dollars.  None  of  the  vaults  was 
exposed  to  severe  direct  heat,  but  considerable  damage  to  con- 
tents was  occasioned  by  water.  As  a  result  of  experience  gained 
in  this  fire,  Mr.  F.  J.  T.  Stewart  of  the  National  Board  of  Fire 
Underwriters  gives  the  following  conclusions  and  recommen- 
dations. 

Vaults.  —  Public  safe  deposit  vaults  and  others  intended  to 
practically  guarantee  the  safety  of  their  contents  against  damage 
of  any  kind  should  be  designed  to  provide  positive  protection 
against  fire,  water  and  impact. 

Such  a  vault  should  erribody  the  following  characteristics: 
An  outer   casing  of   concrete   at  least    12  inches   thick   to 

*  Report  of  National  Fire  Protection  Association  Committee  on  "Vaults 
and  Safes." 


SAFES,  VAULTS,  METAL   FURNITURE,  ETC.          835 

insulate  against  heat,  and  so  reinforced  with  steel  as  to  have  ample 
strength  to  resist  impact.  The  foundations  should  rest  directly 
on  the  ground  and  be  of  masonry  or  of  structural  steel  designed 
with  a  large  factor  of  safety.  The  steel  .to  be  fireproof ed  with 
reinforced  concrete  at  least  6  inches  thick.  The  foundations  as 
well  as  the  floor,  roof  and  sides  of  vault  should  be  independent 
of  the  building  structure. 

There  should  be  an  inner  shell  of  steel,  at  least  If  inches 
thick,  provided  with  sufficient  clearance  so  that  any  moderate 
deflection  of  the  outer  casing  would  not  crush  it.  The  outer 
masonry  casing  and  the  inner  steel  shell  should  be  waterproofed; 
likewise  the  vestibule  doors  should  be  stepped  and  packed  so  as 
to  prevent  smoke  or  water  from  entering.* 


METAL  FURNITURE,  ETC. 

Its  Raison  d'etre.  —  The  fundamental  ideas  which  have  led 
to  the  greatly  extended  use  of  metal  furniture,  etc.,  during  the 
past  few  years:  are,  1. —  to  prevent  incipient  fires  through  the 
use  of  incombustible  furniture  and  fittings,  etc.,  2. —  to  prevent 
the  spread  of  fire,  and,  3. —  to  reduce  the  combustible  contents 
of  buildings  to  a  minimum. 

1.  The  use  of  metal  furniture,  like  that  of  metal  trim,  is  a 
great  factor  in  fire  prevention.     A  gas-jet  or  an  overheated  stove 
will  not  start  fire  in  surrounding  trim  if  the  latter  be  of  metal. 
Similarly,  a  burning  scrap-basket  will  not  ordinarily  start  fire 
in  an  office  if  under  or  adjacent  to  a  metal  desk. 

2.  While  metal  furniture  may  not  lay  claim  to  any  great 
degree  of  fire-resistance,  still  it  will  not  carry  flame,  and  hence 
incipient  fires  may  be  more  easily  controlled. 

3.  If,  through  exposure  or  otherwise,  fire  is  once  present  in  any 
degree  of  severity,   the  use  of  metal  furniture,   shelving,   etc., 
if  consistently  carried  out,  has  at  least  reduced  the  combustible 
fittings  to  a  minimum. 

It  has,  however,  previously  been  pointed  out  that,  no  matter 
how  fire-resisting  a  building  may  be  made,  this  quality  becomes 
of  no  avail  if  fire  is  once  started  in  a  sufficient  amount  of  com- 
bustible contents.  Hence,  where  any  great  quantity  of  com- 
bustible stock  or  contents  exists,  too  much  reliance  should  not 
be  placed  in  metal  fittings  or  shelving,  etc.,  to  hold  such  stock, 
but  auxiliary  means  of  protection  should  be  provided  as  explained 
in  following  chapters. 

*  See  "  Report  on  Fire  in  the  Equitable  Building." 


836         FIRE   PREVENTION   AND   FIRE    PROTECTION 

Advantages  of  Use.  —  The  great  province  of  metal  furniture, 
etc.,  is  to  prevent  the  origin  and  spread  of  fire  —  not  to  withstand 
it.  But,  besides  being  incombustible,  it  is  durable,  sanitary, 
unaffected  by  moisture,  and  impervious  to  vermin.  Withal,  it  is 
susceptible  of  very  pleasing  finishes  in  baked  enamel  coatings, 
lacquers  or  electro-plates. 

Increasing  Use  of.  —  A  great  variety  of  furniture,  fittings, 
etc.,  suitable  for  offices  of  all  kinds,  stores,  banks  and  public 
buildings,  is  now  made  by  the  leading  companies  engaged  in  this 
line  of  business.  The  catalogs  of  the  Art  Metal  Construction 
Co.,  Jamestown,  N.  Y.,  —  The  Library  Bureau,  New  York  and 
Boston,  etc.,  —  the  Van  Dorn  Iron  Works  Co.,  Cleveland, 
Ohio,  —  The  Berger  Manufacturing  Co.,  Canton,  Ohio,  —  and 
of  other  firms  making  these  products,  both  illustrate  and  de- 
scribe the  wide  range  of  articles  now  made  in  steel.  The  gradu- 
ally increasing  cost  of  wood  vs.  improvements  in  processes  of 
manufacture  of  steel  products  is  steadily  tending  to  equalize 
the  first  cost. 

The  use  of  metal  filing  cases,  desks,  counter  fittings,  etc.,  in 
offices  and  banks  is  now  familiar  to  all,  but  a  four-story  office 
building,  fitted  throughout  with  metal  furniture,  is  still  something 
of  a  novelty.  This  is  true,  however,  of  the  Administration 
Building  of  the  Larkin  Co.,  Buffalo,  N.  Y.,  in  which  not  only  the 
doors,  trim,  etc.,  are  of  steel,  but  all  desks,  tables,  chairs,  filing 
cases,  showcases,  lockers  and  even  hat-  and  coat-racks  are  of  the 
same  material. 

The  use  of  metal  furniture  and  filing  cases,  etc.,  is  particularly 
applicable  to  buildings  or  rooms  used  for  the  storage  of  valuable 
papers  or  documents,  such  as  governmental  offices,  state  houses, 
city  halls,  court  houses  and  the  like.  Some  states  have  already 
passed  laws  prohibiting  the  use  of  wood  or  other  combustible 
furniture  or  trim  in  rooms  containing  documents  of  public  record. 
Had  such  furniture  been  installed  in  the  Capitol  building  at 
Albany,  N.  Y.,  priceless  historical  documents  might  have  been 
saved.  It  was  doubtless  this  object  lesson  which  led  to  the  fire- 
test  which  was  held  in  the  courtyard  of  the  Senate  office  build- 
ing, Washington,  D.  C.,  May  3,  1911,  to  determine  the  relative 
value  of  wood  and  steel  filing  cases.  The  result  plainly 
demonstrated  that  steel  cases  can  be  subjected  to  a  fire-test 
of  considerable  severity  without  destroying  the  papers  contained 
therein. 


SAFES,  VAULTS,  METAL    FURNITURE,  ETC.  837 

Steel  Shelving.  —  In  retail  and  wholesale  stores,  factories, 
and  the  like,  the  usual  highly  combustible  wood  shelving  used  for 
the  storage  of  goods  may  be  replaced  with  great  advantage  as 
regards  room,  strength,  resistance  to  vermin,  and  noncombus- 
tibility,  by  adjustable  metal  shelving  on  metal  uprights.  The 
" Simplex"  steel  shelves,  manufactured  by  the  Van  Dorn  Iron 
Works  Co.,  are  of  this  character. 


CHAPTER  XXVIII. 
SPECIAL   HAZARDS. 

Special  Hazards,  in  insuraace  phraseology,  denote  those 
hazards  which  are  incident  to  special  processes  of  manufacture 
involving  considerable  fire  risk.  See  page  313.  As  here  used, 
special  hazards  are  intended  to  cover  certain  fire  dangers  which 
arise  from  the  storage  or  handling  of  especially  dangerous  mate- 
rials, or  other  special  dangers,  such  as  lightning,  to  which  all 
classes  of  building  construction  are  liable. 

Spontaneous  Combustion.  —  The  chemistry  of  spontaneous 
ignition  is  simple.  Decomposition  is  a  slow  combustion.  The 
human  body  slowly  burns  to  ashes  in  the  grave.  Oxygen  uniting 
with  carbon  produces  heat.  If  they  unite  rapidly  enough,  in 
sufficient  quantities,  the  combustion  is  visible  in  flame.  If  they 
unite  slowly,  as  in  the  decay  of  organic  bodies,  the  heat  escapes 
unnoticed.  Rapid  chemical  action  will  start  visible  combustion 
as  easily  as  the  application  of  the  torch. 

Oils,  etc.  —  Vegetable  oils,  spread  over  easily  carbonized  sub- 
stances, such  as  cotton  rags  or  waste,  will  ignite  the  latter  very 
quickly.  The  cotton  fibre  furnishes  a  sort  of  tinder.  Animal 
fats,  like  tallow,  butter  and  lard,  especially  if  rancid,  will  ignite 
under  conditions  similar  to  the  above,  but  they  are  not  such  great 
offenders  as  the  vegetable  oils  —  cottonseed,  nut,  castor  bean, 
olive  and  especially  linseed. 

Prof.  John  H.  Bryan,  principal  of  the  ward  schools  of  Marion, 
Indiana,  stated  at  a  recent  meeting  of  school  superintendents 
that  twice  he  had  found  mops  used  by  the  janitor  in  oiling  the 
floor,  burned  to  ashes,  it  being  evident  that  the  building  each 
time  narrowly  escaped  being  fired.  To  prove  the  nature  of  the 
trouble  Prof.  Bryan  saturated  several  mops  with  the  oil  and  hung 
them  up  in  a  safe  place  for  observation.  A  mop  saturated  with 
oil  at  5  p.m.  was  found  to  be  very  warm  at  7  a.m.,  and  in  one 
instance  a  mop  was  watched  until  it  burst  into  flame.  It  is 
possible,  indeed  probable,  that  many  fires  reported  as  of  "  in- 
cendiary" or  ''mysterious"  origin,  result  from  such  causes,  for 

838 


SPECIAL   HAZARDS  839 

unless  such  fires  are  discovered  at  their  inception,  they  soon 
destroy  all  evidence  as  to  origin. 

The  products  of  petroleum,  such  as  kerosene,  gasolene  and 
naphtha,  do  not  ignite  spontaneously,  but  rags  or  waste  saturated 
therewith  constitute  a  great  hazard,  due  to  their  highly  inflam- 
mable nature. 

Wool.  —  The  possibility  of  spontaneous  ignition  occurring 
in  raw  wool  has  long  been  discussed.  Heretofore  the  general 
opinion  seems  to  have  been  that  wool  will  not  take  fire  spon- 
taneously. An  investigation,  however,  discloses  some  well 
authenticated  cases  of  fires  in  wool  which  undoubtedly  originated 
from  this  cause,  and  leads  to  the  conclusion  that  under  certain 
conditions  fires  in  some  kinds  of  wool  may  take  place  from 
spontaneous  ignition.* 

Charcoal.  —  See  paragraph  " Steam  Pipes,"  page,  840. 

Coal.  —  The  spontaneous  combustion  of  coal  begins  with  slow 
oxidation  where  the  heat  developed  cannot  be  carried  away. 
Dust  and  fine  coal  expose  large  surfaces  to  oxidation.  Rehan- 
dling  stored  coal  after  the  first  oxidation  largely  prevents  further 
heating. 

An  investigation  into  the  spontaneous  combustion  of  coal 
made  by  Prof.  S.  W.  Parr  and  Mr.  F.  W.  Kressman,  of  the  Uni- 
versity of  Illinois,  f  suggests  the  following  precautionary  measures 
as  regards  the  storage  of  coal: 

(1)  Avoidance  of  external  sources  of  heat;  (2)  elimination  of 
dust;  (3)  dry  storage;  (4)  artificial  treatment  with  chemicals; 
(5)  preliminary  heating  to  effect  the  initial  stages  of  oxidation;^ 
and  (6)  submerging  the  coal  in  water. 

Similar  recommendations  regarding  the  storage  and  handling 
of  coal  are  given  by  Messrs.  H.  C.  Porter  and  F.  K.  Ovitz,  of  the 
Bureau  of, Standards,  Washington,  D.  C.,  as  follows: 

With  full  appreciation  of  the  fact  that  any  or  all  of  the 
following  recommendations  may  under  certain  conditions  be 
found  impracticable,  they  are  offered  as  being  advisable  pre- 
cautions for  safety  in  storing  coal  whenever  their  use  does  not 
involve  unreasonable  expense. 

(1)  Do  not  pile  over  12  ft.  deep,  nor  so  that  any  point  in 
the  interior  will  be  over  10  ft.  from  an  air-cooled  surface. 

*  For  more  complete  information,  see  "Spontaneous  Ignition  of  Wool,"  by 
Mr.  Benjamin  Richards,  in  National  Fire  Protection  Association's  "Quarterly," 
January,  1911. 

t  See  "The  Spontaneous  Combustion  of  Coal,"  Engineering  News,  May  4, 
1911. 


840         FIRE    PREVENTION    AND    FIRE    PROTECTION 

(2)  If  possible,  store  only  lump. 

(3)  Keep  dust   out  as  much  as  possible;    reduce  handling 
to  a  minimum. 

(4)  Pile  so  that  lump  and  fine  are  distributed  as  evenly  as 
possible;    do  not  allow  lumps  to  roll  down  a  pile  and  form  air 
passages  at  the  bottom. 

(5)  Rehandle  and  screen  after  two  months. 

(6)  Keep  away  external  sources  of  even  moderate  heat. 

(7)  Allow  six  weeks'  "  seasoning  "  after  mining  before  storing. 

(8)  Avoid  alternate  wetting  and  drying. 

(9)  Avoid  admission  of  air  to  interior  of  pile  through  inter- 
stices around  foreign  objects,  such  as  timbers  or  irregular  brick- 
work;  also  through  porous  bottoms,  such  as  coarse  cinders. 

(10)  Do  not  try  to  ventilate  by  pipes,  as  more  harm  than 
good  is  often  done.* 

Steam  Pipes.  — 

A  number  of  investigators  have  attempted  to  produce  fires 
by  bringing  steam  pipes  into  contact  with  various  combustible 
materials,  but  as  the  duration  of  the  experiments  was  compara- 
tively short,  few  actual  fires  resulted.  The  conclusions  generally 
drawn,  however,  were  that  any  steam  pipe,  no  matter  how  low 
the  pressure,  would  in  course  of  time  produce  charcoal,  and  that 
when  this  stage  was  reached  positive  danger  existed.  Charcoal 
is  unquestionably  subject  to  spontaneous  ignition.  This  is  due 
largely  to  its  peculiar  ability  to  absorb  from  the  air  many  times 
its  own  volume  of  oxygen.  This  is  held  in  the  minute  pores,  which 
exist  in  all  forms  of  wood  charcoal.  The  combination  of  this 
oxygen  with  the  carbon  may  take  place  with  sufficient  rapidity 
to  raise  the  temperature  to  the  ignition  point.  Furthermore, 
charcoal  formed  at  a  low  temperature  is  known  to  have  a  low 
ignition  point. f 

The  hazard  of  steam  pipes  is  materially  increased  where  the 
heat  is  in  any  way  confined,  or  where  contact  exists  with  materials 
more  flammable  than  wood.  Steam  pipes  should  especially  be 
insulated  from  materials  subject  to  spontaneous  ignition,  such  as 
oily  waste,  celluloid  or  coal  dust.  Also,  such  insulation  is  more 
important  in  connection  with  high  pressure  pipes  than  where 
piping  is  used  for  exhaust  steam  only. 

Steam  pipes  may  be  kept  free  from  combustible  materials 
either  by  insulating  as  with  a  pipe  jacket,  or  by  supporting  them 
rigidly  at  a  safe  distance. 

*  See  "Deterioration  of  Coal  in  Storage,"  Engineering  News,  January  11, 
1912. 

t  See  "Fire  Dangers  of  Steam  Pipes"  (quoting  actual  fires,  etc.),  by  the 
Independence  Inspection  Bureau,  in  National  Fire  Protection  Association's 
"Quarterly,"  January,  1911. 


SPECIAL   HAZARDS 


841 


Fig.  353*  shows  a  simple  method  of  enclosing  a  pipe  passing 
through  floor.     The  pipe  jacket  is  supported  by  a  screw-collar 


Floor 


Joist 


Ceillngy 


Split  pipe  covering.- 
halves  wired 
together 


^  Split  supporting  collar 


FIG.  353.  —  Protection  of  Steam  Pipe  passing  through  Floor. 

below,  while  a  floor  plate  above  conceals  the  opening  and  protects 
the  end  of  jacket.  On  new  installations  one-piece  covering  and 
collars  may  be  used,  but  if  piping  is  already  in  place,  use  split 
covering,  wired  together,  and  split  collars. 


Lath  and  plaster 
Baseboard    ££$&  »^  Metal  sleeve 


Floor  Line 


Ornamental  dollar 


FIG.  354.  —  Protection  of  Steam  Pipe  passing  through  Partition. 


Fig.  354*  illustrates  a  method  recommended  for  use  in  an 
ordinary  lath  and  plaster  partition.  The  steam  pipe  is  sur- 

*  See  "Fire  Dangers  of  Steam  Pipes"  (quoting  actual  fires,  etc.),  by  the 
Independence  Inspection  Bureau,  in  National  Fire  Protection  Association's 
"Quarterly,"  January,  1911. 


842 


FIRE    PREVENTION    AND    FIRE   PROTECTION 


rounded  by  a  piece  of  pipe  or  tubing  of  sufficient  diameter  to  leave 
an  annular  space  of  at  least  one-half  inch,  which  should  be  filled 
with  asbestos  paper.  The  collars  are  used  for  the  sake  of  ap- 
pearance only. 

In  both  of  the  above  cases,  where  the  piping  passes  through 
combustible  construction,  the  jacket  should  preferably  be  of  the 
full  length  of  the  concealed  space. 

Fig.  355  illustrates  the  second  method  of  protection,  wherein 
the  pipe  is  supported  on  a  bar-iron  bracket  which  may  be  lagged 


Removable 
Strap 


Clearance  at 
least  1J4" 

FIG.  355.  —  Supporting  Brackets  for  Steam  Pipes. 

to  the  woodwork.     The  clamp  strap  is  removable.     At  least  1J 
inches  clearance  from  woodwork  is  advisable. 

In  the  application  of  any  of  these  methods,  the  following 
points  should  be  borne  in  mind: 

First,  that  pipe  coverings  are  not  capable  of  resisting  appre- 
ciable mechanical  strain,  and  that  they  should  be  called  upon  to 
act  as  an  insulator  and  not  as  a  support.  With  small  vertical 
pipes  metal  supports  are,  however,  not  essential. 

Second,  that  cutting  a  large  hole  for  a  steam  pipe  is  not 
sufficient,  as  a  pipe  is  almost  certain  to  sag,  expand,  or  contract, 
and  thereby  come  into  contact  with  the  side  of  hole  in  which  it 
was  at  one  time  central. 

Third,  that  a  steam  pipe  should  be  covered  wherever  it  is 
concealed.  Even  if  there  appears  to  be  no  likelihood  of  any  loose 
combustible  material  getting  onto  pipe  when  same  is  put  in  place, 
there  is  always  danger  of  accumulation  of  rubbish  around  pipes.* 

Gasolene.  —  For  rules  and  regulations  of  the  National  Board 
of  Fire  Underwriters  concerning  the  storage  and  handling  of 
gasolene,  see  "Storage  Tanks,  Piping,  etc./'  in  connection  with 
garages,  page  817.  See,  also,  "Fire  Tests  with  Liquid  Petro- 
leum Products,"  Chapter  XXXII,  page  934. 

*  ibid. 


SPECIAL   HAZARDS  843 


Explosives.*  — 


Section  56.  —  Any  person,  if  authorized  to  sell  gunpowder 
in  the  original  package  only,  may  keep  in  a  store  not  exceeding 
fifty  pounds  of  gunpowder,  in  casks  or  tin  or  copper  canisters,  to 
be  deposited  in  a  metal  receptacle  with  metal  handles,  and  plainly 
marked  " Gunpowder";  and,  unless  otherwise  specified  in  the 
permit,  located  on  the  lower  floor  not  more  than  six  feet  from  the 
entrance  to  the  street,  which  receptacle  shall  at  all  times  be  kept 
locked,  except  when  actually  necessary  to  obtain  access  to  its 
contents. 

Section  57.  —  Any  person  authorized  to  sell  gunpowder  at 
retail  may  keep  in  a  store  twenty-five  pounds  of  gunpowder,  in 
tin  or  copper  canisters  with  tin  or  copper  covers  thereon,  said 
canisters  to  be  deposited  in  a  metal  receptacle  with  metal  handles, 
and  plainly  marked  " Gunpowder;"  and,  unless  otherwise  speci- 
fied in  the  permit,  located  on  the  lower  floor  not  more  than  six 
feet  from-  the  entrance  to  the  street,  which  receptacle  shall  at  all 
times  be  kept  locked,  except  when  actually  necessary  to  obtain 
access  to  its  contents. 

Section  58.  —  Any  person  keeping  gunpowder  or  detonators 
for  sale  shall  have  displayed  over  the  outside  of  the  principal  en- 
trance from  the  street  of  the  store  in  which  such  gunpowder  is 
kept  a  sign  on  which  shall  be  painted  in  capital  letters  the  words 
"Licensed  to  sell  Gunpowder,"  or  detonators,  as  the  case  may  be. 

Section  59.  —  Any  person  may  keep  for  use  not  exceeding 
five  pounds  of  gunpowder  in  a  building  or  other  structure  that  is 
not  a  magazine  and  is  not  used  for  a  dwelling  house,  but  said 
powder  shall  be  kept  in  a  canister  and  located  so  that  it  can  be 
easily  removed  in  case  of  fire. 

Section  62.  —  No  person  shall  be  authorized  to  keep  for 
sale  gunpowder  or  detonators  in  a  building  any  part  of  which  is 
used  as  a  dwelling,  factory  or  school,  or  where  people  are  accus- 
tomed to  assemble. 

Section  63.  —  No  person  shall  be  authorized  to  keep  for 
sale  or  use  gunpowder  or  detonators  in  that  part  of  a  building 
where  crude  petroleum,  gasolene,  naphtha,  benzine,  camphene, 
burning  fluid  or  fireworks  are  stored  or  kept;  and  a  permit  to 
keep  for  sale  gunpowder  or  detonators  may,  in  the  discretion  of 
the  authority  empowered  to  grant  the  same,  be  refused  in  any 
part  or  whole  of  a  building  where  cigars  or  cigarettes,  paints,  oils, 
varnishes,  tar,  pitch,  rosin,  kerosene  or  any  compounds  contain- 
ing any  of  the  above-named  substances  are  kept,  and  in  any  build- 
ing in  which  any  carpenter  shop  or  drug  store  is  located,  or  where 
hay,  cotton  or  hemp  is  stored  or  kept. 

*  For  a  valuable  discussion  concerning  "The  Storage  of  Explosives,  Petro- 
leum, and  Certain  Chemicals  in  Densely  Inhabited  Areas,"  see  Capt.  J.  H. 
Thomson,  Chief  Inspector  of  Explosives,  London,  in  the  British  Fire  Preven- 
tion Committee's  Report  of  the  International  Fire  Prevention  Congress,  Lon- 
don, 1903. 


844         FIRE    PREVENTION    AND    FIRE    PROTECTION 

Section  64.  — All  gunpowder  exceeding  one  pound  in  amount 
shall  be  kept  in  a  substantial  case,  bag,  canister  or  other  recep- 
tacle, made  and  closed  so  as  to  prevent  the  gunpowder  from 
escaping.* 

The  above  regulations  of  the  Detective  and  Fire  Inspection 
Department  of  the  District  Police  of  the  State  of  Massachusetts 
should  be  rigidly  enforced  by  the  chief  of  the  fire  department  in 
any  city  or  town,  or  by  the  chairman  of  the  board  of  selectmen  in 
a  town  not  having  a  fire  department;  notwithstanding  this, 
singular  laxity  regarding  the  hazards  of  explosives  was  disclosed 
by  the  fire  which  somewhat  recently  occurred  at  Lenox,  Mass. 
In  this  instance,  the  burning  of  the  Clifford  Block,  which  resulted 
in  the  loss  of  six  lives,  called  public  attention  to  the  fact  that 
explosives  and  highly  inflammable  substances  had  been  per- 
mitted to  occupy  the  basement  of  a  store,  while  the  upper  floors 
were  devoted  to  dwelling  purposes.  Gunpowder,  dynamite, 
cartridges,  turpentine  and  oils  made  a  combination  which  should 
have  been  prohibited  under  any  conditions,  but  which  was 
nothing  short  of  criminal  in  a  non-fire-resisting  building  used 
also  as  a  dwelling. 

Fireworks.  —  Section  4.  No  permits  shall  be  granted  for  the 
sale  at  wholesale  or  retail  of  fireworks  in  any  premises  used  for 
the  following  purposes: 

a.  Where  paints,  oils,  gasolene  or  other  inflammable  liquid, 
tar,  pitch,  resin,  hay,  cotton,  hemp,  or  other  combustible  fibre 
or  stock  are  manufactured  or  kept  for  sale  or  storage,  or  in  any 
carpenter  shop  or  drug  store. 

6.  Where  dry  goods  of  any  kind  or  other  light  material  of  a 
combustible  nature,  excepting  flags,  paper  lanterns,  paper  balloons, 
decorations  or  newspapers,  are  kept  for  sale;  these  exceptions 
shall  be  stored  or  offered  for  sale  at  a  safe  distance  from  the  fire- 
works. The  accredited  representatives  of  the  Fire  Department 
shall  have  discretionary  powers  in  these  matters. 

c.  On  other  than  a  street  grade  floor. 

d.  Where  gunpowder,  blasting  powder  or  other  high  explo- 
sives are  sold,  or  in  any  structure  considered  specially  hazard- 
ous by  the  Fire  Department. 

e.  Where  cigars  or  cigarettes,  liquors  or  spirits  are  kept  for 
sale. 

Section  5.  —  In  buildings  or  places  in  which  fireworks  are 
stored  or  kept  for  sale  at  wholesale  or  retail,  the  following  regu- 
lations, with  all  others  mentioned  in  this  ordinance,  must  be 
observed,  and  it  shall  be  the  duty  of  the  Chief  of  the  Fire  Depart- 
ment or  his  authorized  agent  to  see  that  they  are  complied  with: 

*  From  the  Regulations  governing  the  Keeping,  Storage,  Manufacture,  Sale 
and  Use  of  Certain  Explosives  in  the  State  of  Massachusetts. 


SPECIAL    HAZARDS  845 

a.  Safety  matches  only  may  be  kept  in  stock,  sold,  given 
away  or  used. 

b.  No  fireworks  shall  be  exposed  for  sale  outside  the  walls 
of  any  building,  nor  in  any  doorway  or  show  window,  and  they 
must  be  kept  remote  from  any  open  flame  or  fire  and  the  direct 
rays  of  the  sun. 

c.  Lighting  must  be  by  electricity  (incandescent)  or  other 
light  acceptable  to  the  Chief  of  Fire  Department. 

d.  Exits,  both  front  and   rear,  to.be  provided   and  kept 
open  or  provided  with  doors  opening  outward. 

Section  7.  —  When  a  permit  is  issued  to  sell  fireworks,  the 
person  or  persons  receiving  the  permit  shall  cause  the  word  "  FIRE- 
WORKS," with  at  least  a  6-inch  black  letter  on  a  red  ground,  to 
be  prominently  exposed  inside  and  outside  of  the  premises. 
There  shall  also  be  exposed  in  close  proximity  to  these  "  Fire- 
works" signs  a  sign  with  at  least  6-inch  black  letters  on  a  white 
ground,  to  read  "No  SMOKING."  It  will  then  be  a  misdemeanor 
during  the  period  for  which  the  permit  has  been  granted  for  any 
person  or  persons  to  enter  said  premises  with  a  lighted  cigar, 
cigarette  or  other  exposed  light  or  fire,  or  to  light  or  to  cause 
same  to  be  lighted  or  burned  therein,  or  for  the  proprietor,  owner 
or  occupant  to  knowingly  allow  such  lighted  or  burning  articles 
to  be  on  the  premises.  The  Chief  of  the  Fire  Department  may 
compel  the  exposing  of  signs  "FIREWORKS"  and  "No  SMOKING" 
in  more  than  one  language.* 

Protection  against  Lightning,  t  —  Reliable  statistics  show 
that  lightning  is  the  cause  of  more  fires,  especially  in  town  or 
country  residences  and  farm  buildings,  than  would  popularly  be 
supposed.  Thus  in  Chapter  XXIV,  of  3,298  fires  in  residences 
where  the  causes  were  known,  272  were  occasioned  by  lightning. 
Mr.  Gerhard  also  cites  a  number  of  instances  in  which  theatre 
buildings  have  been  struck  by  lightning,  some  while  the  per- 
formance was  in  progress.  He  therefore  advises  that  every 
theatre  should  have  sufficient  protection  against  lightning,  as 
such  protection  "may  prevent  the  outbreak  of  fire,  and  may  like- 
wise serve  to  avert  serious  panic." 

Protection  against  lightning  is  usually  advisable  on  country 
buildings,  on  isolated  buildings,  and  on  all  buildings  wherever 
located  having  elevated  features  such  as  tall  chimneys,  steeples, 
high  peaked  or  gable  roofs,  and  flag  poles. 

*  See  "Fireworks  Ordinances,"  suggested  by  the  National  Board  of  Fire 
Underwriters,  1910. 

t  For  a  very  interesting  illustrated  paper  concerning  "Necessary  Practical 
Safeguards  against  Fires  caused  by  Lightning,"  see  Mr.  Alfred  Hands  in  the 
British  Fire  Prevention  Committee's  Report  of  the  International  Fire  Preven- 
tion Congrese,  London,  1903. 


846         FIRE   PREVENTION    AND    FIRE    PROTECTION 

Since  the  amount  of  protection  which  any  building  should 
have  will  depend  upon  its  location,  construction,  nature  of  its 
occupancy  and  the  value  of  the  building  as  compared  with  the 
expense  necessary  to  provide  the  protection,  definite  rules  cannot 
be  laid  down  for  the  installation  of  lightning  conductors,  but  the 
following  general  suggestions  should,  if  carried  out,  give  under 
most  conditions,  reasonable  protection: 

The  ordinary  condition  causing  a  lightning  discharge  is  a 
cloud  charged  with  electricity  at  a  greatly  different  potential 
from  that  of  the  earth.  The  difference  of  potential  is  finally 
sufficient  to  " break  down"  the  stratum  of  air  between  earth  and 
cloud,  and  an  electrical  discharge  takes  place.  The  resistance 
of  the  air  stratum  being  generally  less  between  cloud  arid  tops 
of  buildings  and  other  structures  than  between  cloud  and  earth, 
such  high  points  take  the  discharge,  and  unless  some  less  resistive 
path  is  provided  from  these  points  to  the  ground  than  the  struc- 
ture to  be  protected,  the  lightning  will  follow  the  next  best  course 
to  earth,  generally  causing  damage  to  the  structure  and  fre- 
quently starting  a  fire. 

It  is  also  of  importance  to  note  that  the  discharge  leaves  a 
column  of  heated  air  between  earth  and  cloud.  This  hot  air 
column  may  be  blown  in  one  or  another  direction  and  very  likely 
become  the  path  of  a  second  discharge,  since  it  has  less  resistance 
than  the  surrounding  cooler  air.  This  may  account  for  lightning 
striking  a  structure  below  the  high  points. 

It  is  therefore  desired  to  so  locate  the  conductors  forming 
the  lightning  protection  that  the  lightning  will  strike  these  and 
be  carried  to  earth  instead  of  tearing  through  the  structure  on  its 
way  to  ground.  Such  an  arrangement  of  conductors  suggests  an 
enclosing  cage  with  the  bars,  of  course,  considerably  separated. 
The  idea  of  protection  is  therefore  a  metallic  cage  with  air  ter- 
minal projections  at  the  high  points  of  the  structure  and  the 
whole  protecting  cage  thoroughly  grounded.  Just  what  material 
is  employed  is  not  of  great  importance  provided  it  has  good 
electrical  carrying  capacity,  is  strong,  can  be  bent  and  jointed 
readily,  and  is  not  liable  to  be  seriously  affected  by  corrosion. 
Undoubtedly  copper  in  tape  form  or  ordinary  galvanized-iron 
pipe  best  meet  these  conditions. 

Just  how  far  apart  the  conductors  should  be  will  depend 
very  considerably  upon  conditions,  and  no  general  rule  can  be 
given  for  the  number  of  square  feet  of  ground  area  protected  by 
one  rod  which  will  safely  cover  all  cases.  Since  in  addition  to 
the  high  points  the  most  exposed  parts  of  a  structure  are  the  out- 
posts and  projections,  extra  protection  is  needed  here,  while  a 
much  wider  spacing  of  rods  might  be  sufficient  along  the  sides  of 
the  structure. 

For  rules  of  installation  applying  to  all  structures,  and  for 
specific  suggestions  covering  chimneys,  stacks,  steeples  and  ordi- 
nary buildings,  see  pamphlet  " Protection  against  Lightning" 


SPECIAL   HAZARDS  847 

(from  which  the  above  suggestions  are  abstracted),  issued  by 
the  National  Board  of  Fire  Underwriters  and  by  the  National 
Fire  Protection  Association. 

In  general,  it  may  be  said  that  steel-frame  buildings  are  seldom 
injured  by  lightning,  except  that  flagstaff s  thereon  are  often 
struck.  The  usual  well-grounded  steel  frame  prevents  any 
dangerous  concentration  of  the  electrical  energy.  It  has  not 
yet  been  demonstrated  as  to  how  far  the  metal  reinforcement  of 
concrete  structures  can  carry  lightning  without  injury.  If 
lightning  conductors  are  used  on  concrete  buildings  they  should 
be  of  ample  cross-section,  —  say  1-in.  diam.  pipe,  —  well  grounded, 
and  carried  several  inches  from  the  face  of  wall. 


PART   VI 

AUXILIARY  EQUIPMENT  AND 
SAFEGUARDS 


CHAPTER  XXIX. 
AUXILIARY   EQUIPMENT. 

Requirements  for  Complete  Fire  Protection.  —  It  has 

been  shown  in  previous  chapters  that  an  approved  fire-resisting 
building  must  provide  for  and  comprise  as  its  fundamental  ele- 
ments of  fire-resistance  not  only  a  scheme  of  construction  based 
upon  the  use  of  fire-resisting  materials,  so  as  to  preserve  the 
integrity  of  the  structural  portions  of  the  building  under  fire-test, 
but  also  an  underlying  and  scientific  general  plan  or  design, 
without  which  the  purely  constructional  features  may  fail,  owing 
to  the  absence  of  such  considerations  as  limiting  areas,  cut-offs, 
exposure  risks,  etc.,  etc.,  all  of  which,  in  an  adequate  design,  are 
intended  so  to  reinforce  the  construction  as  to  make  serious  fire 
loss  impossible  under  circumstances  less  severe  than  those  in- 
duced by  conflagrations. 

These  basic  principles  of  fire-resisting  construction  and  design 
are  worthy  of  the  utmost  emphasis  in  any  discussion  of  the  fire 
problem,  for  even  today,  after  the  experiences  of  Baltimore  and 
San  Francisco  and  in  spite  of  the  lessons  taught  by  those  and 
other  fires,  there  is  great,  indeed  almost  universal,  misapprehen- 
sion in  the  lay  mind  as  to  just  what  fire-resisting  building  con- 
struction means,  and  what  degree  of  success  may  be  expected 
from  it  under  certain  conditions.  Previous  to  the  Baltimore  fire 
the  general  public  usually  expected  little  short  of  infallibility 
in  so-called  fireproof  construction.  A  steel  framework  and  a 
floor  system  of  terra-cotta  or  concrete  have  been  heretofore 
largely  sufficient  to  cause  non-professional  judgment  to  assume 
the  consequent  complete  protection  from  fire-damage  of  both 
the  building  and  its  contents.  And  that  these  expectations 
have  not  been  realized  has  been  the  ground  for  much  con- 
demnation or  scoffing  at  " fireproof"  construction  in  general. 

But  fire  protection,  viewed  in  its  broad  and  proper  light,  should 
include  not  only  the  passive  qualities  of  fire-resistance  in  design 
and  construction  but  also  those  active  means  of  fire-detection  and 
fire-fighting  appliances  which  go  so  far  to  supplement  and  make 

851 


852          FIRE    PREVENTION    AND    FIRE    PROTECTION 

effective  the  purely  passive  elements  of  the  problem.  Fire  pro- 
tection should  be  aggressive  as  well  as  purely  resistant. 

Fire  protection  concerns  not  only  the  building,  but  its  contents 
as  well.  Damage  to  contents  is  not  eliminated  by  simply  pro- 
viding an  incombustible  structure  for  their  receipt.  Many  a  fire 
has  spread  quickly  and  swept  through  a  building  with  ultimate 
heavy  loss  on  stock  or  contents,  but  with  comparatively  little 
damage  to  the  structure  itself.  Such  a  result,  while  affording  a 
most  satisfactory  object  lesson  of  the  structural  efficiency  of  the 
building,  might  be  most  gratifying  to  the  owner,  but  most  dis- 
astrous to  the  lessee  of  the  premises.  Efficient  fire  protection 
regards  the  contents  of  equal  importance  with  the  surrounding 
building. 

Again,  fire  protection  means  not  only  the  preservation  of  the 
main  structural  elements  of  the  building  after  being  subjected  to 
fire-test,  but  both  insurance  interests  and  those  of  the  owner 
require  that  repairs  or  reconstruction  shall  be  reduced  to  a  mini- 
mum. Without  auxiliary  appliances  it  is  problematical  how  far 
fire-resisting  construction  per  se  will  accomplish  this  result.  The 
lack  of  automatic  or  supplementary  safeguards  may  easily  mean 
a  fire  of  such  area  and  intensity  as  will  cause  severe  or  even  total 
loss  to  interior  trim  or  finish,  when  the  means  of  immediately 
detecting  the  incipient  blaze  or  the  means  of  limiting  the  resulting 
sweep  of  the  fire  would  have  prevented  such  loss  in  great  or 
complete  measure. 

Quite  apart  from  any  possible  reimbursement  from  insurance 
companies,  it  is  assumed  that  fire  almost  always  causes  financial 
losses  which  cannot  be  made  goocl.  The  merchant,  manufac- 
turer or  mill  owner,  even  if  insured  to  the  full  value  of  his  stock 
or  plant,  cannot  collect  indemnity  for  the  profits  on  unsold  goods, 
or  for  the  serious  interruptions  to  or  entire  loss  of  business  result- 
ing from  repair,  rebuilding,  or  securing  new  quarters,  new  ma- 
chines, new  stock  or  the  necessary  working  paraphernalia  of  his 
business,  and  the  possible  permanent  loss  of  customers.  The 
investor  in  office  buildings  or  other  structures  to  be  leased  cannot 
insure,  at  least  profitably,  the  continuation  of  rents  which  may 
be  cut  off  abruptly,  and  for  a  considerable  period  of  time,  through 
the  agency  of  fire. 

Limitations  of  Fire  Department  Efficiency.  —  A  further 
limitation  placed  upon  purely  passive  or  structural  fire  protection 
is  found  in  the  inability  of  our  city  fire  departments,  through 


AUXILIARY   EQUIPMENT  853 

circumstances  largely  beyond  their  control,  to  handle  many  fires 
with  which  they  are  called  upon  to  cope. 

Since  the  advent  of  the  many-storied .  office  building  in  most 
large  American  cities,  it  has  been  plain  to  those  actively  employed 
in  the  business  of  fighting  fire,  as  well  as  to  those  who  have 
thoughtfully  followed  the  course  of  high-building  construction, 
that  the  days  of  the  ladder  and  hose  in  the  hands  of  courageous 
and  intrepid  firemen  were  gradually  passing  from  their  hitherto 
unquestioned  fire-fighting  sufficiency  to  partial  if  not  complete 
impotence  where  the  high  building  is  concerned. 

This  fact  had  been  partially  realized  in  the  early  nineties, 
while  office  buildings  were  rapidly  developing  from  the  modest 
ten  stories  of  the  Home  Insurance  Company's  Building  in  Chicago 
—  the  pioneer  of  skeleton  construction  methods  —  to  the 
twenty-storied  Masonic  Temple  in  the  same  city,  and  the  Man- 
hattan Life  Building  in  New  York  City;  but  it  was  not  until 
1898,  when  the  Home  Life  Building  in  New  York  City  was 
almost  completely  destroyed  by  fire  above  the  eighth  story,  that 
it  became  clear  to  those  most  intimately  engaged  in  the  fire 
problem  —  viz.,  the  municipal  fire  department  —  that  new  fire- 
fighting  facilities  would  have  to  be  relied  upon  more  and  more 
in  the  successful  coping  with  fire  above  the  ordinary  range  of  the 
department's  efficient  efforts. 

Home  Life  Building  Fire.  —  As  has  been  pointed  out  in 
Chapter  VI,  the  burning  of  the  Home  Life  Building  —  a  sixteen- 
story  office  building  which  was  considered  thoroughly  fire-resist- 
ing according  to  the  standards  of  its  day  —  demonstrated  the 
fact  that,  notwithstanding  the  most  modern  apparatus  of  the 
.  New  York  City  Fire  Department,  it  was  impossible  to  combat 
the  flames  successfully  above  the  eighth  story,  at  least  after  the 
fire  had'  assumed  serious  proportions.  In  other  words,  modern 
portable  fire  apparatus  is  not  and  cannot  be  made  efficient  for 
fire-fighting  purposes  above  the  limit  of  about  125  feet  above  the 
street  level,  while  in  dangerous  risks  the  limit  of  efficiency  is  even 
less  than  this.  This  is  practically  equivalent  to  saying  that  fire 
once  established  above  the  tenth  floor  of  modern  high  buildings 
must  be  left  to  burn  itself  out,  as  far  as  portable  department 
apparatus  is  concerned. 

Parker  Building  Fire.  —  The  fire  in  the  twelve-story  Parker 
Building  in  New  York  City,  also  described  in  Chapter  VI, 
illustrates  most  forcibly  the  limitations  of  fire  department 


854          FIRE   PREVENTION   AND   FIRE   PROTECTION 

efficiency,  and  the  necessity  for  auxiliary  equipment.  The  follow- 
ing extracts  are  taken  from  the  report  on  this  fire,  made  by  Mr. 
W.  C.  Robinson,  Chief  Engineer  of  the  Underwriters'  Labora- 
tories, to  the  New  York  Board  of  Fire  Underwriters. 

So  far  as  I  am  aware,  this  is  the  first  case  on  record  where 
a  so-called  fireproof  building  and  its  contents  have  been  so  ex- 
tensively damaged  by  a  fire  starting  within  the  building.  Such 
an  occurrence  in  the  largest  city  in  the  country,  and  in  a  district 
receiving  the  full  protection  of  a  supposedly  well-equipped  and 
efficient  fire  department,  was  generally  unexpected.  That  the 
destruction  of  such  a  building  is  not  only  possible,  but  quite 
probable,  makes  it  imperative  that  requirements  for  the  intro- 
duction of  necessary  safeguards  be  provided  and  vigorously 
enforced. 

The  Parker  Building  is  understood  to  be  fairly  representa- 
tive of  fireproof  buildings  occupied  for  mercantile  and  light  manu- 
facturing purposes  in  New  York  City,  and  is  said  to  have  been 
of  even  better  construction  than  many  later  buildings.  Its 
practical  destruction,  while  surprising  to  the  general  public,  fur- 
nishes no  reason  for  the  discredit  of  fire-resisting  building  con- 
struction, and  teaches  no  lessons  to  the  fire-protection  engineer 
which  have  not  been  more  or  less  thoroughly  understood.  The 
results  of  this  fire  do,  however,  serve  to  emphasize  the  necessity 
for  better  design,  for  the  more  effective  use  of  the  materials  em- 
ployed in  fireproofing,  and  for  efficient  inside  fire  protection  in 
high  buildings  used  for  the  storage  of  large  quantities  of  com- 
bustible materials. 

A  standard  equipment  of  automatic  sprinklers  with  ample 
water  supply  is  generally  recognized,  at  the  present  time,  as  the 
most  efficient  means  for  protection  of  this  nature,  yet  developed. 

The  large  amount  of  combustible  material  in  the  Parker 
Building,  its  excessive  area,*  inadequately  protected  stair-  and 
elevator-shafts,  and  lack  of  facilities  for  the  prompt  discovery 
of  fire,  furnished  conditions  which  permitted  this  fire  to  gain 
very  great  headway  before  the  arrival  of  the  fire  department. 
The  loss  on  this  building  with  its  contents  under  such  circum- 
stances, directs  attention  to  the  probability  that  under  similar 
conditions  of  construction,  area  and  occupancy,  fires  may  assume 
proportions  beyond  the  control  of  a  well-equipped  fire  department, 
especially  as  unavoidable  delays  due  to  condition  of  the  streets, 
absence  of  nearest  engines  at  other  fires,  etc.,  are  possible  at  any 
time. 

As  his  second  "  conclusion "  regarding  the  more  important 
features  brought  out  by  his  investigations,  Mr.  Robinson  gives 
the  following: 

The  height  of  fireproof  buildings  of  mercantile,  manu- 
facturing or  storage  occupancy  should  be  limited  to  correspond 

*  The  inside  floor  area  was  only  15,000  square  feet. 


AUXILIARY   EQUIPMENT  855 

to  the  degree  of  protection  the  building  equipment  and  the  fire 
department  are  able  to  furnish.  In  other  words,  if  adequate  fire 
protection  in  any  building  is  not  available  above  a  certain  height, 
the  building  should  be  limited  to  such  height. 

In  the  upper  stories  of  high  buildings  filled  with  com- 
bustible contents,  the  greatest  difficulties  are  to  be  found.  Re- 
stricting the  height  of  such  buildings  seems  to  be  the  only  safe 
practice  unless  adequate  internal  fire  protection  be  provided. 

Equitable  Building  Fire.  —  The  fire  which  destroyed  the 
Equitable  Building  in  New  York  City,  January  9,  1912,  again 
demonstrated  the  inability  of  our  public  fire  departments  to 
cope  with  well-developed  fire  in  high  buildings.  Although  only 
eight  stories  high,  this  building  was  of  such  construction  as  to 
make  the  matter  of  fire  extinguishment  far  more  dangerous  and 
difficult  than  in  much  higher,  but  more  modern,  buildings.  Six 
persons,  including  a  battalion  chief  of  the  fire  department,  lost 
their  lives  in  the  fire. 

This  fire,  like  those  in  the  Parker  Building,  Triangle  Shirt 
Waist  Factory,  and  Alwyn  Court  Apartment  House,  calls  atten- 
tion to  the  inability  of  any  fire  department  to  effectively  fight 
a  fire  which  has  once  gained  headway  in  the  upper  stories  of  a 
tall  building  lacking  such  essential  fire  appliances  as  an  adequate 
standpipe  equipment  *  in  conjunction  with  smoke-proof  stair 
towers.  The  height  of  buildings  should  be  limited  in  proportion 
to  the  effectiveness  of  their  fire  protection,  if  life  and  property 
are  to  be  conserved.  .  .  . 

Portable  Steamers.  —  The  inefficiency  of  the  ordinary  port- 
able steam  fire  engine  was  strikingly  apparent  in  contrast  with 
the  high  pressure  streams  from  'the  separate  fire-main  system. 
The  fluctuations  in  pressure  incident  to  stoking  the  boilers  of  the 
portable  steamers  is  an  element  of  weakness,  as  well  as  their 
capacity  and  pressure  limitations.* 

Increase  in  Number  of  High  Buildings.  —  The  difficulty 
experienced  in  fighting  fire  in  high  buildings  may  be  said  to 
increase  about  as  the  square  of  the  height.  Buildings  300  feet 
high  are  no  longer  marked  curiosities  in  New  York  City,  where 
no  building  regulations  limit  the  height  of  structures  (except 
tenements),  and  a  census  of  the  high  buildings  made  in  1907  by 
the  New  York  City  Building  Department  showed  a  total  of  538 
structures  which  were  10  stories  or  more  in  height  —  viz.,  one 
building  (the  Metropolitan  Life  tower)  of  48  stories,  one  of  41, 
two  of  26,  three  of  25,  two  of  23,  four  of  22,  nine  of  20,  two  of  19, 

*  See  "Report  on  Fire  in  the  Equitable  Building,"  by  F.  J.  T.  Stewart, 
Superintendent,  New  York  Board  of  Fire  Underwriters. 


856         FIRE    PREVENTION   AND   FIRE    PROTECTION 

nine  of  18,  two  of  17,  nineteen  of  16,  nineteen  of  15,  eighteen  of 
14,  thirteen  of  13,  one  hundred  and  sixty-nine  of  12,  one  hundred 
and  one  of  11  and  one  hundred  and  sixty-four  of  10  stories.  A 
number  of  other  high  structures  have  been  built  since  then, 
including  the  new  Municipal  Building,  which  is  40  stories  high 
including  the  tower,  or  560  feet  above  the  street  level;  while  the 
Woolworth  Building  is  to  be  the  highest  in  the  world  —  55 
stories,  or  775  feet  in  height  above  the  curb.  In  other  words, 
there  are  probably  over  550  buildings  in  New  York  City  today, 
which,  as  far  as  efficient  fire  protection  is  concerned,  are  above 
the  effective  fire-fighting  range  of  the  fire  department,  when 
working  without  auxiliary  aids;  and  when  it  is  remembered  that 
the  Woolworth  Building,  the  48-storied  tower  of  the  Metropoli- 
tan Life  Building,  —  658  feet  high,  —  the  41-storied  tower  of  the 
Singer  Building,  —  611  feet  high,  —  and  the  Municipal  Building 
before  mentioned,  all  contain  or  will  contain  offices  to  a  height 
greater  than  the  Washington  Monument,  the  necessity  for  every 
possible  form  of  auxiliary  equipment  looking  to  the  discovery  and 
extinguishment  of  fire,  as  well  as  the  need  of  adequate  provisions 
against  smoke  and  panic,  are  sufficiently  apparent. 

While  not  wishing  to  pose  as  an  alarmist,  the  author  ventures 
the  prediction  that  immunity  from  serious  loss  of  life  in  some  tall 
office  building  or  buildings  cannot  be  expected  to  last  indefinitely. 
Many  examples  have  been  built  without  due  consideration  being 
given  either  the  design  of  methods  of  escape,  or  of  auxiliary  equip- 
ment. The  few  and  narrow  stairs  provided  in  many  instances 
mean  that  the  several  hundreds  of  tenants  occupying  many  of 
these  structures  would  find  hurried  exit  by  either  stairways  or 
elevators  impossible,  and  panic  would  soon  result.  The  cause 
need  not  be  serious  to  produce  the  blind,  unreasoning  fear  ex- 
hibited in  panic.  Witness  the  cases  in  which  smoke  alone,  with- 
out serious  danger  of  fire,  has  produced  panic. 

Improvement  not  to  be  found  in  Fire  Departments.  — 
Added  facilities  for  fire  protection  can  not  be  looked  for  in  any 
possible  improvement  of  the  personnel  of  the  fire  departments,  as 
that  has  already  reached  a  high  degree  of  excellence;  nor  in 
added  pumping  capacity  in  fire  engines  sufficient  to  meet  the  new 
demands  of  excessive  height,  although  the  new  high-pressure 
services  lately  installed  in  New  York  and  other  cities  will  prove 
of  immense  value  in  high-building  fires;  nor  in  heavier  or  stronger 
hose  made  to  withstand  the  bursting  pressure  induced  by  great 


AUXILIARY   EQUIPMENT  857 

heights,  even  though  criticism  might  be  made  regarding  the 
bursting  of  poor  hose,  as  was  the  case  at  the  Parker  Building  fire; 
nor,  in  fact,  in  new  portable  apparatus  of -any  kind  which  would 
solve  the  problem.  The  only  possible  remedies  lie,  therefore,  in 
the  improved  design  and  construction  of  high  buildings,  and  in  the 
employment  of  auxiliary  fire-detecting  and  fire-fighting  appliances. 

Value  of  Time  at  Outbreak  of  Fire.  —  Again,  however  per- 
fect the  fire  department,  an  average  time  of  perhaps  five  minutes 
elapses  between  the  discovery  of  fire  and  the  arrival  of  the  depart- 
ment on  the  spot  for  effective  working.  In  the  meantime  what 
is  taking  place?  Since  minutes  are  as  hours  where  the  spread  of 
fire  is  concerned,  are  automatic  means  at  work  during  those 
minutes  to  forestall  even  the  prompt  firemen?  Are  the  occupants 
of  the  structure  working  orderly  and  effectively  to  quench  the  fire 
by  means  of  appliances  provided  for  just  such  an  emergency,  or 
is  the  fire  left  in  undisputed  sway  in  the  premises,  because,  for- 
sooth, the  fire  department  will  soon  arrive  and  be  all-sufficient? 
The  manner  in  which  the  first  few  minutes  are  employed  usually 
determines  whether  the  loss  is  to  be  trifling,  or  whether  the  fire 
has  gained  such  headway  as  to  involve  the  whole  premises. 

Value  of  "First  Aid"  and  Automatic  Appliances.  —  In  an 
editorial  commenting  on  a  number  of  fires  which  have  destroyed 
costly  non-fire-resisting  buildings  and  their  contents,  Engineering 
News  (May  23,  1907)  stated  as  follows: 

Such  fires  often  reveal  that  complete  reliance  had  been 
placed  on  the  protection  afforded  by  the  municipal  fire  depart- 
ment service,  and  no  attempt  made  to  provide  local  facilities  for 
"  first  aid."  If  water  under  pressure  is  supplied  to  the  structure, 
one  or  more  fire  plugs  and  hose  coils  on  each  floor  can  do  excellent 
service  in  an  emergency.  In  the  absence  of  a  water  supply, 
portable  fire  extinguishers  are  a  useful  resource.  In  either  case 
there  should  be  some  organization,  some  arrangement  of  duties 
which  will  ensure  that  these  protective  devices  are  called  into  use 
promptly  upon  the  outbreak  of  fire.  There  are  very  few  instances 
where  it  is  impracticable  to  provide  these  means  of  auxiliary  pro- 
tection. There  are  still  fewer,  if  any,  where  such  protection 
would  not  prove  its  value  in  the  case  of  a  fire. 

This  criticism  is  as  applicable  to  fire-resisting  buildings  as  to 
non-fire-resisting. 

Furthermore,  it  ought  to  be  much  more  fully  realized  that  either 
" first  aid"  or  automatic  appliances  are  far  more  potent  in  fire 
protection  than  reliance  on  hose  streams  in  the  hands  of  the  fire 
department. 


858          FIRE   PREVENTION   AND   FIRE   PROTECTION 

In  an  address  (1906)  before  the  Fire  Underwriters'  Association 
of  the  Northwest,  Mr.  U.  C.  Crosby  stated  that: 

The  improvement  resulting  from  intelligent  consideration 
of  individual  risks  has  reached  such  a  stage  of  perfection  that  the 
destruction  of  a  "  standard  plant "  is  practically  impossible ;  and 
we  are  insuring  —  at  a  profit  —  at  one-fifth  of  one  per  cent.,  or 
less,  risks  we  wrote  not  long  ago  at  many  times  that  rate,  at  a  loss. 
For  years  we  have  worked  to  increase  the  number  of  pails,  stand- 
pipes  and  hydrants,  and  to  add  to  the  water  supply,  and  yet  the 
total  destruction  of  risks  continues  without  much  diminution. 
Experience  brought  us  another  viewpoint  and  proved  that  fires 
could  be  controlled  only  by  eliminating  as  far  as  possible  hazards 
and  dangerous  features,  and  then  applying  the  fire  extinguisher 
in  the  first  stage  of  a  fire.  The  automatic  sprinkler  and  not  the 
hose  stream  was  the  dominant  factor  in  the  transformation. 

Such  an  expression  of  conviction  from  a  fire  protectionist  of 
the  wide  experience  of  Mr.  Crosby  is  significant. 

Extinguishment  of  Fires  by  Hose  Streams.  —  An  inquiry 
into  the  statistics  of  hose  streams  and  the  part  played  by  them  in 
extinguishing  fires  reveals  many  facts  which  are  distinctly  con- 
trary to  public  opinion.  While  adequate  water  supplies,  auxili- 
ary pipe-systems,  hydrants  and  standpipes,  etc.,  are  all  important 
requisites  for  fire  protection,  it  will  not  do  to  assume  that  the 
mere  presence  of  such  means  is  potent,  or  even  that  the  use  of 
such  means  will  necessarily  be  effective.  Neither  the  presence 
nor  the  mere  use  of  water  are  deciding  factors  in  the  extinguishing 
of  fire.  Water  is  only  potent  when  used  effectively,  i.e.,  either 
early  enough  in  the  progress  of  the  fire  to  permit  a  small  quantity 
completely  to  extinguish  the  blaze,  or,  in  later  stages,  in  sufficient 
volume  to  be  effective  after  making  due  allowances  for  the  water 
lost  by  evaporation  or  inefficient  application.  Witness  fires  in 
water-front  properties,  where  there  is  an  inexhaustible  supply  of 
water  which  usually  adds  not  at  all  to  reducing  the  loss;  also  the 
Asch  Building  fire,  mentioned  in  next  paragraph. 

As  to  the  part  played  by  the  hose  streams  of  public  fire  depart- 
ments in  the  initial  extinguishment  of  fires,  a  classification  of  the 
alarm  fires  which  occurred  in  Greater  New  York  during  the  year 
1908  will  show  that,  out  of  a  total  of  8,642  fires 
5,258   were  extinguished  without  an  engine  stream. 
2,657   were  extinguished  with  one  engine  stream. 

562   were  extinguished  with  either  two  or  three  engine  streams. 

165   were  extinguished  with  more  than  three  engine  streams, 
or  with  high  pressure  streams. 


AUXILIARY   EQUIPMENT  859 

Thus,  in  about  60  per  cent,  of  the  total  number  the  fires  were 
extinguished  either  by  means  of  " first  aid"  in  the  hands  of  ten- 
ants or  those  on  the  premises,  or  by  means  of  hand  appliances, 
chemical  extinguishers,  etc.,  in  the  hands  of  the  firemen;  while  in 
only  about  8  per  cent,  of  the  total  number  of  fires  did  the  water 
supply  prove  an  important  factor.  In  the  same  year  the  New 
York  Fire  Department  was  estimated  to  have  used  191,791,955 
gallons  of  water  (of  which  over  77,000,000  gallons  were  river 
water),  or  less  than  one  day's  average  consumption  —  a  really 
insignificant  consideration  as  far  as  water  supply  is  concerned. 

In  London,  England,  in  1902,  out  of  3,574  fires  for  the  year 
(not  including  706  chimney  fires) : 

2,910   were  extinguished  by  persons  not  belonging  to  the  fire 
brigade,  or  by  the  use  of  buckets  or  hand  pumps. 

566   were   extinguished   by   water   and   pressure   direct   from 
hydrant. 

98   were  extinguished  by  stream  fire  engines.* 

Hence,  "  water  is  only  one  factor  in  fire  extinction,  and  to 
exploit  it  to  the  neglect  of  others  which  are  just  as  important  is 
simply  misleading  the  public  and  advancing  the  idea  that  de- 
pendence for  safety  from  fire  may  be  placed  on  public  systems, 
whereas  all  experience  is  showing  that  the  individual  must  rely 
more  and  more  on  self-protection."  f 

Efficiency  of  Hose  Streams.  —  The  statistics  given  in  the 
preceding  paragraph  show  that  a  great  majority  of  fire  alarms  are 
responded  to  so  quickly  by  the  fire  department  that  the  blaze  can 
be  handled  by  means  of  chemical  extinguishers,  but  in  those  cases 
where  the  fire  is  beyond  such  control,  the  presence  of  smoke  is 
very  liable  to  make  the  seat  of  fire  obscure  and  unreachable  by 
hose  streams,  even  if  the  smoke  is  not  over-powering.  The 
problem  then  becomes  how  to  apply  water  effectively  to  an  un- 
seen or  undistinguishable  seat  of  fire. 

As  to  the  efficiency  of  hose  streams  after  a  fire  has  attained  any 
considerable  magnitude,  it  will  be  found  that  our  public  fire 
departments  usually  realize  their  impotence,  and  their  efforts  are 
mainly  directed  to  prevent  the  spread  of  flame  to  adjoining  or 
nearby  buildings,  rather  than  to  saving  the  first  structure.  Any 
fairly  large  and  well-stocked  non-fire-resisting  building  represents 

*  See  British  Fire   Prevention  Committee's  Report  of   International  Fire 
Prevention  Congress,  1903,  page  111. 
t  See  Journal  of  Fire,  December,  1906, 


860          FIRE    PREVENTION    AND    FIRE    PROTECTION 

combustible  material  enough  to  make  a  fire  greater  than  any 
reasonable  application  of  water  will  control. 

Extinguishment  of  fire  by  water  requires  that  water  shall 
be  applied  with  sufficient  rapidity  to  take  up  the  heat  as  rapidly 
as  it  is  generated  by  the  fuel.  If  the  heating  effect  is  greater  than 
the  cooling  effect,  the  water  passes  into  steam  or  is  decomposed. 
One  pound  of  fuel,  depending  on  its  nature,  will  evaporate  from 
four  to  twenty-eight  pounds  of  water;  the  floors  and  contents  of 
ordinary  buildings  cannot  be  taken  as  requiring  actual  applica- 
tion of  less  than  six  pounds  of  water  per  pound  of  ignited  fuel. 
Take  a  six-story  brick  and  joisted  construction  building,  60  X 
150  feet,  mixed  tenantry.  Here  the  floors  and  contents  would 
reasonably  weigh,  say  2000  tons,  and  burn  within  three  hours,  or, 
when  well  on  fire,  at  the  rate  of  twelve  tons  per  minute.  This 
calls  for  at  least  seventy  tons  of  water  per  minute  to  quench  the 
fire,  or  the  capacity  of  twenty  steamers,  allowing  for  no  waste. 
Good  judges  believe,  and  I  think  with  good  reason,  that  not  one- 
fourth  to  one-tenth  of  the  water  thrown  by  hose  is  effective.  At 
that  rate  eighty  steamers  and  upward  would  be  required  to  arrest 
fire  in  a  fairly  large  building.  All  there  is  about  such  fires,  and 
many  fires  in  smaller  buildings,  is  that  the  fires  are  not  put  out. 
The  seat  of  the  fire  burns  out,  and  the  village  or  city  department, 
by  holding  walls  and  wetting  exposures,  limits  its  spread.* 

The  possible  waste  of  water  and  the  inability  of  hose  streams 
to  penetrate  any  considerable  distance  beyond  the  windows  were 
well  exemplified  in  the  Asch  Building  fire  in  New  York.  Fig.  41 
admirably  illustrates  how  both  waste  and  inefficiency  increase 
with  the  building's  height. 

Necessity  for  Auxiliary  Appliances. — All  of  these  considera- 
tions go  to  show  the  absolute  necessity  of  reinforcing  even  the  best 
fire-resisting  design  and  construction  with  such  auxiliary  means  or 
appliances  as  will  insure  the  utmost  possible  immunity  from  fire 
loss  to  the  building  itself,  its  contents,  its  rental  value,  or  any  other 
business  interests  connected  therewith.  Hence,  to  the  considera- 
tions of  design  and  construction  covered  by  previous  chapters  must 
now  be  added  a  third  element  of  approved  fire  protection,  namely, 
that  of  equipment,  or  the  installation  of  those  safeguarding  fea- 
tures which  are  designed  to  supplement  the  plan  and  construction : 

1.  By  providing  means  for  automatically  detecting  or  con- 
trolling fire  within  the  premises. 

2.  By  giving  added  security  to  the  structure  or  its  contents 
through  means  which  may  always  be  at  the  hand  of  tenants  or 

*  See  "Limitations  and  Use  of  Water  for  Fire  Extinguishing,"  by  Albert 
Blauvelt,  in  "Transactions  of  National  Fire  Protection  Association,"  1897. 


AUXILIARY   EQUIPMENT  861 

employees  thus  making  it  possible  to  cope  with  incipient  fires 
without  reliance  upon  the  fire  department. 

3  By  lending  much-needed  assistance  to  the  fire  department 
under  conflagration  conditions,  or  under  circumstances  of  great 
height  area  01  exposure  hazard,  where  limitations  of  effective 
fire-fighting  by  the  public  fire  department  are  known  to  exist. 

4.  By  preventing  panic  or  loss  of  life  among  employees  or  ten- 
ante  by  so  forestalling  disaster  as  to  turn  flight  and  panic  into 
orderly  exit  and  pre-arranged  fire-fighting  effort  with  the  means 
at  hand. 

It  may  be  objected  that  all  of  this  apparent  expense  and  trouble 
tc  provide  auxiliary  aids  casts  seeming  discredit  upon  the  effi- 
ciency of  the  splendidly  equipped  and  organized  fire  departments 
in  our  large  cities,  and,  as  such  departments  are  popularly  sup- 
posed to  be  capable  of  handling  all  fires,  the  property  owner 
should  rest  content  in  the  fact  that  he  contributes  through  taxes 
to  the  maintenance  of  the  fire-fighting  force,  and  that  any  addi- 
tional expense  is  superfluous.  Both  of  these  views  are  wholly 
wrong. 

To  emphasize  unduly  either  the  efficacy  of  hose  streams,  or  the 
importance  of  the  fire  department,  is  to  detract  from  the  main 
issue  in  the  matter  of  fire  protection.  The  first  requisite  is  fire 
prevention,  by  removing  as  completely  as  may  be  possible  all  con- 
tributory causes  of  fire.  The  second  requisite  is  fire-resisting 
construction  and  design.  The  third  requisite  ,is  such  means  of 
automatic  or  auxiliary  appliances  as  will  make  each  individual 
structure  independent  of  the  public  fire  department,  at  least  to 
a  degree  sufficient  to  cope  with  incipient  fire,  or  such  as  will 
supplement  fire  department  work  under  conditions  of  extreme 
severity. 

Fires  usually  start  from  some  trifling  and  remedial  cause,  but, 
if  discovered  and  controlled  in  the  initial  stage  by  automatic 
means  or  by  apparatus  and  discipline  designed  to  serve  just  such 
a  purpose,  the  destruction  which  would  otherwise  result  may  be 
practically  eliminated.  Considering  the  possibilities  of  the  ser- 
vice they  may  render,  such  automatic  devices  and  auxiliary  means 
are  of  trifling  expense,  compared  to  the  cost  of  the  otherwise 
incomplete  and  unsatisfactory  structure.  It  would,  therefore, 
seem  as  though  the  great  added  security  imparted  to  any  busi- 
ness or  building  interest  through  these  means  is  neglected  either 
from  false  notions  of  economy,  a  too  close  scrutiny  into  the  first 


862         FIRE   PREVENTION   AND   FIRE   PROTECTION 

cost  only,  or  else  from  ignorance  or  skepticism  as  to.  their  great 
value. 

Principal  Auxiliary  Aids.  —  The  principal  auxiliary  aids  in 
detecting  or  extinguishing  incipient  fires,  or  in  coping  with  par- 
ticularly severe  fires,  or  in  preventing  panic  and  confusion  among 
employees  consist  of  the  following,  which  will  be  treated  in  suc- 
ceeding chapters. 

1.  Automatic    Sprinklers.  —  These    should    be    ranked    first 
among  auxiliary  aids,  because  they  both  detect  and  extinguish 
fire. 

2.  Automatic  Fire  Alarms,  ranked  second  in  importance  be- 
cause of  their  automatic  functions  in  discovering  fire. 

3.  Human  Agencies,  such  as  Fire  Pails;  Extinguishers,  etc.; 
Auxiliary  Boxes;  Watchmen  and  Watch-clocks;  Standpipes;  Hose- 
racks  and  Roof  Nozzles;  Private  Fire  Department. 

4.  Discipline  of  tenants  and  up-keep  of  appliances,  to  insure 
instant  efficiency,  involve : 

Fire  Drills,  and  Inspection  and  Maintenance  of  Protective 
Appliances. 


CHAPTER  XXX. 
SPRINKLER   SYSTEMS. 

Types  of  Sprinkler  Systems.  —  The  various  types  of  sprink- 
ler systems  in  common  use  comprise : 

1.  The  automatic  wet-pipe  system,  used  in  interiors  of  build- 
ings.    This  is  the  ordinary  type,  and  is  often  referred  to  simply 
as  "Sprinklers"  or  "Automatic  Sprinklers." 

2.  The  automatic  dry-pipe  system,  used  for  interiors  of  build- 
ings when  locations  or  conditions  make  the  wet-pipe  arrange- 
ment impossible  or  inadvisable. 

3.  Open  sprinklers,   used  for  the  protection  of  exteriors  of 
buildings. 

4.  Basement  sprinklers,  for  use  in  basements,  sub-basements, 
or   other   inaccessible    places  —  often    called    "perforated    pipe 
systems." 

AUTOMATIC  WET-PIPE  SYSTEMS. 

Principles  of  Automatic  Sprinklers.  —  Automatic  sprink- 
lers are  a  device  for  distributing  water  by  means  of  valves  or 
"heads"  which  are  arranged  to  open  automatically  under  the 
action  of  heat,  as  from  a  fire  which  they  are  intended  to  ex- 
tinguish. The  distribution  of  water  which  results  from  properly 
located  sprinklers  occurs  in  the  form  of  a  rain  of  jets  or  drops,  and 
is  usually  sufficient  to  drench  any  inflammable  stock  beyond  the 
point  of  ignition.  The  distribution  of  water  effected  is  the  most 
economical  possible,  as  the  source  is  directly  above  the  fire,  and 
the  water  is  more  uniformly,  and  hence  more  effectively,  applied 
than  from  a  hose  stream. 

Automatic  sprinkler  protection  is  based  upon  the  principle  of 
discovering  and  controlling  a  fire  at  its  point  of  origin,  thus  in- 
suring a  minimum  fire  loss  to  building  or  contents,  combined  with 
a  minimum  use  of  water.  This  principle  requires  for  its  basic 
elements  the  protection  of  all  areas,  the  quick  and  positive  action 
of  the  heads,  and  an  adequate  supply  of  water  under  sufficient 
pressure. 

863 


864         FIRE   PREVENTION   AND   FIRE   PROTECTION 

Given  these  elements,  the  ordinary  mercantile  or  manufactur- 
ing risk  becomes  almost  nil,  provided  the  system  be  adequately 
inspected  and  maintained.  This  statement  will  be  amplified  and 
illustrated  statistically  in  later  paragraphs  in  this  chapter, 
and  in  Chapter  XXXVI  where  the  inspection,  maintenance, 
and  central  station  supervision  of  sprinkler  equipments  are 
considered  more  at  length. 

Early  Application  of  Sprinkler  Idea.*  —  The  basic  idea  of 
the  sprinkler,  i.e.,  that  fire  may  be  extinguished  through  the 
agency  of  its  own  heat,  is  by  no  means  new  or  recent.  As  early 
as  1723  a  crude  contrivance  to  serve  this  end  was  patented  by 
Ambrose  Godfrey,  an  English  chemist,  in  the  form  of  a  cask  of 
fire-extinguishing  solution  to  be  operated  by  gunpowder  and  a 
system  of  fuses. 

Further  efforts  in  a  similar  direction  were  made  from  time  to 
time  until,  in  1809,  Sir  William  Congreve,  an  inventor  and  hy- 
draulic engineer  of  considerable  note,  patented  a  system  of  rose 
sprinklers,  or  perforated  valve  outlets,  controlled  by  combustible 
cords.  This  system  was  devised  for  the  protection  of  British 
arsenal  buildings,  but  in  1812  this  inventor  discarded  the  use  of 
burning  cords  and  substituted  therefor  a  cement  "  fusible  at  110 
degrees  or  less."  In  this  patent  the  functions  of  an  automatic 
sprinkler  are  stated  to  be  "an  apparatus  for  extinguishing  fires 
which  shall  be  called  into  action  by  the  fire  itself  at  its  first  break- 
ing out,  and  which  shall  be  brought  to  bear  upon  the  precise  part 
where  the  flames  exist,"  a  most  comprehensive  description  of  the 
automatic  sprinkler  as  used  to-day.  The  mechanical  skill  of  the 
inventor,  however,  did  not  equal  his  conception  of  the  problem 
and  little  came  of  the  invention,  or  several  attempts  to  improve 
upon  it,  until  a  half  century  later,  when,  in  1864,  Major  A. 
Stewart  Harrison,  eminent  in  various  fields  of  activity,  as  mili- 
tary engineer,  inventor  and  author,  "made  the  invention  which 
included  the  greatest  advance  made  by  any  one  inventor  up  to 
the  present  date."  Major  Harrison  not  only  invented  a  practical 
sprinkler  head,  but  a  complete  sprinkler  system  as  well,  including 
piping  to  be  hung  from  the  ceiling  with  heads  placed  six  to  ten 

*  For  data  regarding  the  development  of  automatic  sprinklers  the  author 
is  indebted  to  the  article  "Modern  Development  and  Early  History  of  Auto- 
matic Sprinklers,"  published  in  Cassier's  Magazine,  1892,  by  Mr.  C.  J.  H. 
Woodbury,  formerly  vice-president  Boston  Manufacturers'  Mutual  Fire  Insur- 
ance Company. 


SPRINKLER   SYSTEMS  865 

feet  apart,  according  to  the  character  of  the  rooms'  contents,  an 
elevated  supply  tank  for  insuring  a  constant  head  of  water,  check 
valves,  fire-alarm  bell  to  be  operated  by  the  opening  of  any  head 
and,  in  fact,  all  of  the  essential  features  of  a  modern  installation. 

Invention  of  Fusible  Solder.  —  The  greatest  advance  in  this 
invention  lay  in  the  use  of  fusible  solder  for  the  release  of  the 
head.  Low  fusible  alloys  now  so  commonly  used  in  automatic 
sprinklers  were  first  made  by  Sir  Isaac  Newton,  while  master  of 
the  mint  in  1699.  He  it  was  who  discovered  the  fact  that  certain 
alloys  possess  lower  melting  points  than  any  of  their  constituents. 
The  lowest  alloy  which  he  produced  was  made  of  bismuth,  lead 
and  tin,  melting  at  212  degrees  Fahrenheit.  This  melting  point 
has  been  reduced  through  later  experiments.  The  solder  now 
generally  used  has  a  fusion-point  of  about  165  degrees  Fahrenheit, 
being  made  of  bismuth  4  parts,  lead  2,  tin  1  and  cadmium  1  part. 
Some  such  alloy  was  used  in  sprinkler  heads  for  the  first  time  by 
Major  Harrison. 

First  Successful  Sprinkler.  —  The  first  successful  automatic 
sprinkler  from  a  commercial  standpoint,  i.e.,  to  be  manufac- 
tured and  sold  for  service  in  protecting  property,  was  that 
patented  by  Henry  S.  Parmelee,  of  New  Haven,  August  11,  1874. 
This  head  consisted  of  a  slotted  revolving  cap,  or  "reaction  tur- 
bine," the  whole  being  covered  with  a  brass  jacket  which  was 
soldered  at  its  bottom  rim  to  a  flange  on  the  head  casting.  The 
whole  arrangement  was  "simple  in  construction,  secure  against 
leakage  and  so  efficient  in  its  operation  at  hundreds  of  fires  as  to 
open  a  new  era  in  fire  protection  of  manufacturing  establishments 
and  to  modify  methods  of  insurance;"  but  as  the  heads  were  of 
the  type  known  as  "water-joint"  sprinklers,  because  the  seal 
could  not  be  melted  until  the  entire  sprinkler  and  the  water  with- 
in the  jacket  were  raised  to  the  melting  point  of  the  solder,  the 
action  was  relatively  slow. 

Development  of  Sprinkler  Heads,  etc.  —  For  a  more  ex- 
tended account  of  the  development  of  sprinkler  heads,  etc., 
reference  should  be  made  to  the  authoritative  article  by  Mr. 
C.  J.  H.  Woodbury,  before  referred  to,  and  to  Crosby  and  Fiske's 
"Handbook  of  Fire  Protection  for  Improved  Risks,"  where 
illustrations  of  117  different  sprinkler  heads  are  given. 

Invention  of  Fusible  Link.  —  To  the  late  Edward  Atkinson, 
for  so  many  years  the  President  of  the  Boston  Manufacturers' 
Mutual  Fire  Insurance  Company,  and  the  sponsor  of  the  now 


866         FIRE    PREVENTION   AND   FIRE   PROTECTION 

well-recognized  principles  of  mill-  or  slow-burning  construction, 
is  due  the  invention  of  the  first  fusible  link,  made  of  two  pieces 
of  brass  soldered  together  with  a  thin  film  of  fusible  alloy.  This 
link  was  originally  devised  for  use  in  connection  with  self-operat- 
ing hatches,  doors  and  shutters,  but  the  principle  was  of  far 
greater  value  when  applied  to  the  struts  of  automatic  sprinklers, 
for  the  reason  that  sprinkler  solder,  when  used  in  mass,  is  weak, 
inelastic  and  subject  to  " crawling"  by  cold  flow.  Links  or  bars 
made  of  solid  solder  had  always  failed  by  stretching  or  breaking, 
and  the  conception  of  the  film  link  did  much  to  develop  practical 
sprinkler  heads  of  a  sensitive  nature. 

Applicability  of  Sprinkler  Protection.  —  Unfortunately, 
the  idea  has  heretofore  been  all  too  prominent  that  sprinkler  sys- 
tems are  intended  for  use  only  in  non-fire-resisting  buildings,  and 
even  so,  principally  to  secure  a  reduction  in  the  insurance  pre- 
mium. The  thought  of  protection  to  the  structural  portions  of 
the  building,  or  protection  to  contents,  has  often  been  secondary 
to  the  thought  of  reduced  insurance  charges,  as  in  the  case  of  the 
manufacturer  who  was  interviewed  by  the  selling  agent  of  an 
automatic  sprinkler  company,  and,  after  hearing  of  the  numerous 
virtues  of  the  device  offered  for  sale,  replied:  " Young  man,  I 
don't  care  what  you  put  up.  You  can  put  up  rosettes  if  they  will 
satisfy  the  insurance  man."* 

Among  fire  protectionists,  however,  and  among  broad-minded 
and  far-seeing  manufacturers,  merchants  and  owners,  sprinkler 
equipment  is  becoming  more  and  more  generally  recognized  as 
equally  applicable  and  valuable  in  connection  with  fire-resisting 
construction,  particularly  because  of  its  automatic  nature,  and 
the  consequent  protection  afforded  to  both  structure  and  con- 
tents; and  many  structures  of  steel-frame  and  terra-cotta  or 
concrete  construction  are  now  being  provided  with  this  device. 

For  warehouses,  factories,  and  wholesale  and  retail  store  build- 
ings, automatic  sprinklers  should  invariably  be  installed,  even 
where  these  structures  are  of  the  most  approved  fire-resisting 
type.  Indeed,  laws  requiring  the  uniform  equipment  with 
sprinklers  of  all  manufacturing,  storage  or  mercantile  buildings 
within  the  congested  areas  of  large  cities  are  being  most  seriously 
discussed  as  the  most  practicable  safeguard  against  further 
conflagrations. 

*  See  Ira  G.  Hoagland,  inspector  of  Southeastern  Tariff  Association,  in 
March,  1907,  "Journal  of  Fire." 


SPRINKLER   SYSTEMS  867 

In  theatres,  sprinklers  are  a  valuable  auxiliary  means  of  con- 
trolling fire,  as  is  described  in  Chapter  XXII.  In  office  buildings 
the  use  of  sprinklers  is  hardly  to  be  expected  to  any  considerable 
extent,  partly  on  account  of  the  unusually  large  tenantry,  thus 
making  probable  a  prompt  discovery  and  handling  of  fire,  and 
partly  on  account  of  the  comparatively  slight  hazard  from  com- 
bustible contents;  but  in  unusually  high  office  buildings,  where 
the  upper  floors  are  beyond  the  effective  fire-fighting  operations 
of  the  city  fire  department,  the  use  of  sprinklers  is  strongly  to  be 
recommended. 

Extended  Use  of  Sprinklers.  —  The  widely  extended  use  of 
sprinkler  installation  is  indicated  by  an  estimate  made  by  Mr. 
Henry  A.  Fiske,  one  of  the  leading  sprinkler  insurance  authorities 
in  the  United  States,  viz.,  that  between  25,000  and  50,000  build- 
ings in  the  United  States  are  now  protected  by  automatic  sprink- 
lers, aggregating  a  property  value  of  thousands  of  millions.  It 
has  also  been  estimated  that,  in  the  New  England  states,  about 
one-third  of  the  liability  of  all  of  the  fire  insurance  companies 
covers  property  protected  by  sprinklers.  This  is  a  remarkable 
record  when  one  remembers  that  the  first  sprinkler  risk  to  be 
installed  in  New  York  City  under  the  approval  of  the  New  York 
Board  of  Fire  Underwriters  did  not  occur  until  the  year  1884. 
Up  to  and  including  the  year  1905,  605  approved  sprinkler  in- 
stallations were  made  in  Greater  New  York  and  the  immediate 
vicinity,  the  maximum  yearly  number  being  69  in  1892.  The 
use  of  sprinklers  has,  however,  developed  most  markedly  in  the 
large  mill  or  manufacturing  centers,  and  for  this  reason  New 
England  has  proved  one  of  the  most  prolific  fields,  on  account  of 
the  numerous  cotton  and  woolen  mills,  shoe  factories  and  the 
like.  But,  although  principally  used  in  storage  or  manufacturing 
buildings,'  it  must  not  be  supposed  that  sprinkler  equipments  are 
limited  only  to  these  classes  of  structures.  Fire-resisting,  as  well 
as  non-fire-resisting,  retail  and  wholesale  stores,  theatres,  hotels, 
and  many  other  types  of  buildings  have  been  either  partially  or 
fully  equipped  with  sprinklers,  and  new  uses  for  this  form  of 
protection  are  continually  being  found. 

Requisites  for  Sprinkler  Protection.  —  The  requisites  for 
efficient  automatic  sprinkler  protection  are: 

1.  The  building  must  be  properly  designed,  open  in  construc- 
tion, without  concealed  spaces  where  water  thrown  from  sprinklers 
cannot  penetrate,  and  also  without  unprotected  vertical  openings. 


868         FIRE   PREVENTION    AND    FIRE    PROTECTION 

2.  The  sprinklers  must  be  located  so  that  their  distribution  of 
water  will  cover  all  parts  of  the  premises. 

3.  The  sprinkler  "heads"  must  be  of  approved  make,  and  of 
a  sensitiveness  of  automatic  action  suitable  to  the  particular 
conditions  of  location  and  occupancy. 

4.  The  sprinkler  piping  must  be  of  sufficient  capacity  and 
must  be  under  water-pressure  at  all  times,  except  where  dry-pipe 
system  is  used. 

5.  The  available  water-supply  must  at  all  times  be  of  sufficient 
quantity  and  pressure. 

6.  The  sprinkler  system  must  be  equipped  with  proper  check- 
and  gate-valves,  in  order  to  regulate  the  pressure  from  power 
supplies  and  in  order  to  make  possible  the  shutting  off  of  all  water 
supplies  for  purposes  of  repair. 

7.  Some  approved  type  of  alarm  valve  must  always  be  in- 
stalled as  a  part  of  the  system. 

8.  The  system  as  a  whole  and  in  all  its  details  must  be  thor- 
oughly inspected  at  suitable  intervals,  maintained  in  efficiency, 
and  be  under  the  constant  supervision  of  some  employee  who  is 
perfectly  familiar  with  its  operation  and  repair;  or  else  under 
central  station  supervision. 

All  of  these  conditions  are  essential  to  obtain  proper  automatic 
sprinkler  protection. 

The  installation  of  sprinkler  systems  is  now  usually  performed 
under  the  rules  and  regulations  recommended  by  the  Associated 
Factory  Mutual  Insurance  Companies  or  by  the  National  Fire 
Protection  Association. 

These  rules  and  regulations  cover  years  of  experience  in  the 
equipment  of  sprinklered  risks,  and  of  careful  experiment,  both 
on  the  part  of  insurance  interests  and  on  the  part  of  the 
many  manufacturers  of  sprinkler  equipment.  They  are  amended 
and  changed  from  time  to  time  as  experience  shows  may  be 
necessary.* 

Type  of  Building.  —  The  type  of  building  construction  does 
not  necessarily  affect  the  efficiency  or  the  general  scheme  of 
sprinkler  equipment,  save  only  that  the  building  interior  must 
be  open,  without  concealed  spaces,  hollow  walls  or  floors,  unpro- 
tected closets,  etc.  Any  reasonable  peculiarities  of  building 

*  The  latest  rules  and  requirements  for  "Sprinkler  Equipments"  may  be 
had  by  applying  to  the  National  Board  of  Fire  Underwriters,  135  William  St., 
New  York  City,  or  to  the  Secretary  of  the  National  Fire  Protection  Association, 
87  Milk  St.,  Boston,  Mass. 


SPRINKLER    SYSTEMS  869 

design  may  be  provided  for  in  the  sprinkler  equipment,  but,  after 
it  is  once  installed,  no  changes  should  be  made  in  closets,  parti- 
tions, or  other  sub-divisions  of  space  without  consultation  with 
the  underwriters  having  jurisdiction. 

One  prevalent  fault  in  building  construction  should  invariably 
be  corrected  where  sprinklers  are  used  —  namely,  vertical 
openings.  Vertical  draughts  through  buildings  are  detrimental 
to  the  proper  action  of  sprinklers,  and  all  vertical  light-wells, 
flues,  stairways,  etc.,  should  be  " stopped"  or  shut  off  at  the 
various  floors. 

If  the  building  is  of  mill  construction,  it  should  be  built  strictly 
in  accordance  with  the  principles  of  slow-burning  construction 
given  in  Chapter  IV. 

Location  of  Sprinkler  Heads.  —  It  has  been  stated,  as  a 
fundamental  principle  of  sprinkler  protection,  that  the  sprinkler 
heads  must  be  so  located  as  to  insure  a  proper  distribution  of 
water  to  all  parts  of  the  premises.  This  is  one  of  the  most  im- 
portant axioms  of  sprinkler  protection,  and  yet  it  is  frequently 
violated.  Sprinklers  are  intended  to  control  incipient  fire.  No 
one  can  state  or  guess  where,  any  more  than  when,  this  is  liable 
to  occur.  If  the  sprinkler  is  not  there  at  the  origin  to  do  its  work 
of  extinguishment,  or  at  least  of  control,  the  trifling  start  may 
soon  become  of  such  widespread  area  or  intensity  as  to  be  beyond 
the  control  of  many  sprinkler  heads.  It  is,  therefore,  well  to 
remember  that  sprinkler  installation  is  like  fire-resisting  con- 
struction. If  it  is  worth  undertaking  at  all,  it  is  worth  doing  well. 
A  few  additional,  sprinklers  to  make  security  doubly  sure  will 
amount  to  little  in  comparison  with  the  cost  of  the  whole  in- 
stallation. 

Usual  requirements  call  for  "  sprinklers  to  be  placed  through- 
out premises,  including  basement  and  lofts,  under  stairs,  inside 
elevator  wells,  in  belt,  cable,  pipe,  gear  and  pulley  boxes,  inside 
small  enclosures,  such  as  drying  and  heating  boxes,  tenter  and 
dry  room  enclosures,  chutes,  conveyor  trunks  and  all  cupboards 
and  closets  unless  they  have  tops  entirely  open  and  are  so  located 
that  sprinklers  can  properly  spray  therein.  Sprinklers  not  to  be 
omitted  in  any  room  merely  because  it  is  damp,  wet,  or  of  fireproof 
construction. 

Experience  teaches  that  sprinklers  are  often  necessary  where 
seemingly  least  needed. 

The  fallacy  of  attempting  to  pick  out  the  places  where  a 
fire  will  or  will  not  start  has  long  been  proven.  Vacant  base- 


870         FIRE    PREVENTION    AND    FIRE    PROTECTION 

ments,  blind  attics,  concealed  spaces,  etc.,  all  need  sprinkler 
protection.  Two  mills  equipped  with  sprinklers  were  total  losses, 
due  to  the  fact  that  fire  originated  over  the  water  in  canal  or  tail 
race,  and  under  the  building,  i.e.,  in  places  where  it  seemed  next 
to  impossible  for  a  fire  to  start.* 

The  standard  spacing  or  distribution  of  sprinkler  heads  is  as 
follows : 

For  mill  construction  ceilings,  that  is,  smooth  solid  plank 
flooring  laid  over  solid  wooden  girders,  one  line  of  sprinklers  must 
be  placed  in  the  center  of  each  bay,  and  the  distance  between  the 
sprinkler  heads  on  each  line  must  not  exceed  the  following : 

8  feet  in  12-foot  bays, 

9  feet  in  11-foot  bays, 

10  feet  in  10-foot  bays, 

11  feet  in    9-foot  bays, 

12  feet  in  6-  to  8-foot  bays. 
Measurements  to  be  taken  c.  to  c.  of  timbers. 

For  smooth  sheathed  or  plastered  ceilings  not  broken  into  bays 
by  girders  or  other  projections  below  the  ceiling  line,  outlets  to 
be  placed  every  ten  feet  each  way  of  building,  thus  making  100 
square  feet  of  area  for  each  head. 

For  smooth  sheathed  or  plastered  ceilings  broken  into  bays  by 
girders,  etc.,  one  line  of  sprinklers  to  be  placed  in  the 'center  of 
each  bay,  the  distance  between  the  sprinklers  on  each  line  not  to 
exceed 

8  feet  in  12-foot  bays, 

9  feet  in  1 1-foot  bays, 

10  feet  in  6-  to  10-foot  bays. 

Bays  between  12  and  23  feet  in  width  to  contain  at  least  two 
lines  of  sprinklers.  Bays  over  23  feet  wide  to  contain  lines  not 
over  10  feet  apart. 

For  ceilings  of  open  joist  construction  with  bridging  between 
and  plank  flooring  over,  the  distance  between  heads  must  not 
exceed  8  fest  at  right  angles  to  joists,  or  10  feet  parallel  with 
joists.  This  is  veritable  fire-trap  construction,  for  even  sprinkler 
sprays  cannot  reach  the  spaces  between  the  joists,  outside  of  a 
very  small  radius. 

Sprinkler  heads  should  be  located  (as  per  the  above  regula- 
tions) on  the  ceiling  piping  in  an  upright,  not  pendent,  position, 
with  tops  of  sprinkler  heads  not  nearer  than  3  inches  nor  more 

*  "Handbook  of  Fire  Protection  for  Improved  Risks,"  Crosby  and  Fiske. 


SPRINKLER   SYSTEMS 


871 


than  10  inches  below  the  ceiling  or  bottom  of  joists.  This  is  in 
order  that  the  heads  may  be  shielded  by  the  pipes  from  damage 
from  below,  in  order  that  they  may  be  thoroughly  drained  when 
the  system  is  emptied  of  water,  and  in  order  that  sediment  may 
not  collect  at  the  orifice. 

Sprinkler  Heads.  —  Automatic  sprinkler  heads  consist  of 
sealed  orifices  which  are  arranged  to  open  automatically  under  a 
predetermined  temperature.  The  usual  types  (see  following 
illustrations)  are  made  with  a  threaded  connection  at  the  bottom 
(for  attachment  to  the  piping),  at  the  upper  end  of  which  is  the 
valve  seat,  consisting  of  a  one-half  inch  orifice,  closed  by  a  valve 
which  is  held  in  position  by  a  strut  extending  up  to  the  deflector 


FIG.  356.  —  "Grinnell"  Sprinkler 
Head. 


FIG.  357.  —  "Manufacturers" 
Sprinkler  Head. 


or  splash  plate  which  is  supported  by  a  yoke  or  pair  of  arms. 
The  principal  variations  in  the  types  of  sprinkler  heads  are  found 
in  the  details  of  the  valves  and  the  struts  which  keep  them  closed. 
The  valves  are  made  of  metal,  porcelain  or  glass  disks  or  caps 
which  are  held  from  opening  upward  (under  the  water  pressure 
in  the  piping)  by  the  strut  wrhich  extends  from  the  top  of  the 
valve  to  the  deflector  plate  above.  These  struts  are  the  most 
important  part  of  a  head,  for  it  is  in  them  that  the  automatic 
functions  are  incorporated.  This  automatic  action  is  accom- 
plished by  building  up  a  strut  of  component  parts,  held  together 
by  fusible  solder.  When  this  solder  is  softened  by  the  degree 
of  heat  under  which  it  was  intended  to  operate,  the  strut  collapses 
and  the  valve  is  released  under  the  water  pressure.  The  escap- 


872 


FIRE    PREVENTION   AND    FIRE    PROTECTION 


ing  water,  in  a  solid  one-half  inch  stream,  strikes  the  deflector 
above,  and  is  then  scattered  in  the  form  of  spray. 

Figs.  356,  357,  358  and  359  illustrate  four  approved  sprinkler 
heads  —  the  Grinnell  at  half  size,  the  Manufacturers  and  the 


FIG.  358. — "International' 
Sprinkler  Head. 


FIG.   359.  —  "Esty"  Sprinkler  Head. 


International  at  one-fourth  size,  and  the  Esty  at  half  size.  Fig. 
360  shows  the  Grinnell  head  in  cross-section,  while  Fig.  361 
shows  the  same  head  fully  open,  both  to  half  size. 


x-X^ 


FIG.  360.  —  Cross-section  of  "Grin- 
nell"   Head. 


FIQ.  361.  —  "Grinnell"   Sprinkler 
Head,  Open. 


The  solder  used  in  the  ordinary  or  low  test  sprinkler  heads 
fuses  at  from  155  degrees  to  165  degrees,  this  temperature  being 


SPRINKLER    SYSTEMS 


873 


sufficiently  high  for  all  ordinary  locations,  as  even  the  highest 
summer  heat  seldom  exceeds  125  degrees.  For  locations  where 
this  temperature  is  liable  to  be  exceeded, '" hard  heads"  must  be 
used,  employing  solder  which  melts  at  212  degrees,  as  in  engine 
rooms,  low  temperature  dry  rooms,  or  near  steam  piping  —  or 
at  286  degrees,  as  in  boiler  rooms  and  ordinary  dry  rooms. 
Sprinklers  of  360  degrees'  operation  are  sometimes  employed 
over  open  fire,  or  in  very  high  temperature  dry  boxes,  but  they 
are  not  to  be  recommended.  A  safe  rule  for  solder  temperature 
is  to  allow  about  50  degrees  higher  than  the  maximum  tempera- 
ture to  be  expected  in  the  location. 

Pipe  Sizes.  —  In  1896  a  conference  was  brought  about  be- 
tween the  various  insurance  interests  of  the  United  States  for 
the  purpose  of  determining  upon  some  " standard"  rules  and  reg- 
ulations of  sprinkler  practice,  especially  as  regarded  the  schedule 
•of  pipe  sizes.  Previous  to  that  time  the  standard  schedule  of 
the  Providence  Steam  and  Gas  Pipe  Company  —  instituted  in 
1878  by  Frederick  Grinnell  in  connection  with  the  manufacture 
of  perforated  pipes  for  fire  protection  —  had  generally  been  used 
as  a  basis,  but  amendments  from  time  to  time  by  various  in- 
surance organizations  gradually  led  to  considerable  diversity  of 
practice.  The  1896  conference,  out  of  which,  fortunately,  grew 
the  National  Fire  Protection  Association,  adopted  a  standard 
schedule  for  pipe  sizes  which  has  since  been  changed  to  the  follow- 
ing uniform  standard : 


Size  of  pipe. 

Max.  no. 
of  sprinklers 
allowed. 

Size  of  pipe. 

Max.  no. 
of  sprinklers 
allowed. 

f-inch 

1 

3-inch 

36 

1-inch  

2 

3i-inch  .  .  . 

55 

IJ-inch 

3 

4-inch 

80 

IJ-inch  

5 

5-inch  

140 

2-inch 

10 

6-inch 

200 

2|-inch  

20 

It  is  desirable  that  not  more  than  eight  heads  be  placed  on  any 
one  branch  line. 

Feed  Mains. — The  feed  mains,  or  the  horizontal  supply  pipes 
which  feed  the  branches,  should  always  be  arranged  so  as  to  pro- 


874 


FIRE    PREVENTION    AND    FIRE    PROTECTION 


vide  "Centre-Central"  feed,  as  illustrated  by  Fig.  362,  or  " Side- 
Central"  feed,  as  illustrated  by^Fig.  363.     "End"  feed,  or  any 


FIG.  362.  —  "Center-central"  Feed  Mains. 

arrangement  of  piping  whereby  the  risers  which  supply  the  hori- 
zontal feed  pipes  are  brought  up  at  any  end  location  in  the 


FIG.  363.  —  "Side-central"  Feed  Mains. 

building,  are  unapproved.     The  best  arrangement  of  piping  for 
a  large  building  is  shown  in  Fig.  364.* 


FIG.  364. —  Best  Method  of  Piping  Large  Building. 

Risers.  —  Separate  vertical  riser  pipes  must  be  supplied  in 
each  building,  or  in  each  section  of  a  building  divided  by  fire  walls. 
The  size  of  each  riser  must  be  sufficient  to  supply  all  of  the 
sprinkler  heads  on  any  one  floor  (as  determined  by  the  previously 

*  From  "Handbook  of  Fire  Protection  for  Improved  Risks." 


SPRINKLER   SYSTEMS  875 

given  schedule  of  sizes),  the  assumption  being  that  no  vertical 
openings  exist,  and  that  therefore  each  floor  is  a  unit. 

Where  there  is  a  sufficient  number  of  sprinklers  on  any  one 
floor  to  require  a  6-inch  riser,  or  where  the  sprinklers  on  any  one 
floor  exceed  the  number  allotted  to  a  6-inch  pipe,  it  is  preferable 
to  have  two  or  more  smaller  risers. 

Water  Supply.  —  Acceptable  water  supplies  for  sprinkler  ser- 
vice may  be  furnished  by : 

Public  waterworks  supply, 

Private  reservoir  or  stand  pipe, 

Gravity  tank, 

Air-pressure  tank,  or 

Pump,  taking  water  from  approved  source,  such  as  reservoirs 
or  cisterns  of  sufficient  capacity. 

The  choice  of  water  supplies  in  each  instance  is  to  be  deter- 
mined by  the  underwriters  having  jurisdiction. 

Two  independent  water  supplies  are  absolutely  essential  for 
the  best  equipment.  This  is  in  order  that  one  supply  may  always 
be  available  in  case  the  other  is  temporarily  out  of  service,  and 
also  in  order  that  a  primary  supply  of  limited  capacity  or  light 
pressure  may  be  reinforced  by  a  secondary  supply.  At  least  one 
of  the  supplies  must  be  capable  of  furnishing  water  under  heavy 
pressure,  in  order  that  the  opening  of  the  first  sprinklers  may 
prove  wholly  efficient.  This  supply  usually  consists  of  either  an 
elevated  gravity  tank  or  an  air-pressure  tank.  The  second  supply 
must  be  automatic,  and  is  usually  provided  by  the  city  pressure 
taken  from  the  public  water  mains.  More  than  two  supplies  are 
often  advisable.  "A  desirable  combination  for  the  country  risk 
is  pressure  tank,  gravity  tank,  and  steam  pump;  and  for  many 
city  risks,  public  waterworks  and  pressure  tank."* 

Public  Waterworks.  —  The  public  waterworks  supply  should 
be  sufficient  to  give  a  good  pressure  at  all  hours  to  the  highest 
line  of  sprinkler  heads,  preferably  not  less  than  25  pounds  static 
pressure  when  sprinklers  are  open  and  fire  streams  are  playing. 
No  water  supply  for  sprinklers  should  pass  through  a  meter  or 
pressure  regulating  valve,  as  such  devices  cut  down  the  flow  of 
water  by  means  of  friction  and  obstructions.  They  are  also 
unreliable,  and  beyond  the  control  of  the  .assured. 

Gravity  Tanks  should  be  so  placed  that  the  bottom  of  tank 
in  each  case  is  not  less  than  25  feet  above  the  highest  line  of 

*  Crosby  and  Fiske,  Handbook. 


876         FIRE   PREVENTION    AND    FIRE   PROTECTION 

sprinklers  supplied.  This  should  be  a  minimum,  and  if  an  ele- 
vation of  40  or  50  feet  can  be  obtained,  so  much  the  better,  as 
the  efficiency  of  the  tank  naturally  increases  with  the  elevation. 
Otherwise  commendable  sprinkler  equipments  are  rendered  ques- 
tionable as  to  ultimate  efficiency  through  the  single  fact  of  light 
water  pressure. 

For  tank  capacity,  the  National  Board  Rules  specify  5,000 
gallons  as  minimum,  but  10,000  gallons  is  a  desirable  minimum 
on  all  but  the  smallest  risks.  On  the  assumption  of  20  gallons 
per  minute  per  sprinkler,  this  would  feed  25  sprinklers  for  20 
minutes. 

For  large  risks  with  hazardous  occupancy,  or  where  the 
conditions  favor  the  opening  of  more  than  say  25  sprinklers, 
larger  tanks  should  be  used.  Twenty-five  thousand  gallons  should 
be  amply  adequate  where  the  tank  supplies  automatic  sprinklers 
only.  The  size  tank  needed  for  any  given  risk  is  dependent  upon 
so  many  conditions  that  no  fixed  rules  can  be  made,  and  con- 
struction, occupancy,  outside  aid,  and  additional  water  supplies 
must  all  be  taken  into  account.  With  10,000  gallons  as  a  mini- 
mum for  good  class  of  construction  and  occupancy,  with  city 
water  or  other  good  water  supply,  and  25,000  gallons  as  a  maxi- 
mum for  poor  construction  and  occupancy,  tank  capacities  for 
risks  between  these  grades  can  be  easily  approximated.* 

These  sizes  are,  however,  too  small  for  any  but  the  smallest 
plants;  and  25;000  to  75,000  or  even  100,000  gallons  capacity 
are  ordinary  capacities  for  large  industrial  plants. 

On  cylindrical  wooden  gravity  tanks,  band-iron  hoops  should 
never  be  employed,  owing  to  their  tendency  to  rust.  Wrought- 
iron  rod  hoops,  not  less  than  three-fourths  inch  diameter,  without 
welds,  should  invariably  be  used. 

Air-pressure  Tanks  should  be  located  either  on  the  top  floor 
of  building  or  preferably  on  the  roof.  The  capacity  should  never 
be  less  than  4,500  gallons.  This  requires  a  tank  72  inches  diam- 
eter and  22  feet  long  or  66  inches  diameter  and  25  feet  long.  The 
tank  must  be  kept  two-thirds  full  of  water,  and  an  air  pressure 
maintained  over  the  water  of  not  less  than  75  pounds,  so  as  to 
insure  not  less  than  15  pounds  pressure  at  the  highest  line  of 
sprinklers  when  all  water  has  been  discharged  from  the  tank. 

Fire  Pumps,  whether  steam  or  electric,  may  take  water  from 
the  public  service  mains,  or  from  other  approved  source,  but  make 
and  full  installation  must  be  in  strict  accordance  with  the  National 
*  Crosby  and  Fiske,  Handbook. 


SPRINKLER   SYSTEMS  877 

Board  Rules  and  Requirements.  Capacity  must  be  determined 
by  the  underwriters  having  jurisdiction. 

Steamer  Connections.  —  Whatever  the  water  supply  for 
sprinkler  systems,  outside  or  sidewalk  connections  which  permit 
of  the  direct  attachment  of  fire  engines  to  the  risers  are  strongly 
to  be  recommended.  These  should  be  not  less  than  4-inch,  fitted 
with  a  straightway  check-valve,  and  be  located  so  as  to  provide 
for  prompt  and  easy  attachment  of  hose.  A  10,000-gallon  tank 
may,  under  severe  circumstances,  be  emptied  in  10  minutes  if 
50  sprinklers  happened  to  be  open  at  once.  The  value  of  a  hose 
inlet  connection  is,  therefore,  apparent. 

Each  hose  connection  must  be  designated  by  raided  letters  at 
least  one  inch  in  size,  cast  in  the  fitting,  and  reading  "  Automatic 
Sprinkler." 

Cheek-  and  Gate-valves.  —  These  can  be  discussed  more 
understandingly  in  connection  with  questions  pertaining  to 
inspection  and  maintenance,  for  which  see  Chapter  XXXVI. 

Alarm  Valves.  —  To  prove  acceptable  risks,  new  automatic 
sprinkler  installations  must  be  accompanied  by  automatic  alarm 
valves,  installed  on  the  systems,  either  with  or  without  central 
station  supervisory  connection.  This  requirement  is  made  neces- 
sary by  two  very  important  considerations. 

First.  —  Although  statistics  show  that  the  greater  number  of 
fires  in  sprinklered  risks  are  either  practically  or  entirely  extin- 
guished by  the  flow  of  water  from  the  sprinkler  heads  —  as  will 
be  shown  later  —  still,  the  sprinklers  cannot  invariably  be  relied 
upon  to  furnish  complete  protection,  and  human  aid  is  often 
necessary  to  finish  the  work  of  extinguishment.  Hence  it 
becomes  necessary  to  provide  some  means  of  immediate  notifica- 
tion to  tenants,  passers-by,  or  to  some  central  alarm  station,  so 
that  the  fact  of  existing  fire  may  be  at  once  made  known. 

Second.  —  Prompt  notification  of  the  operation  of  the  sprinkler 
system  is  necessary  in  order  to  prevent  the  continued  downpour 
from  heads  after  they  have  been  opened  by  the  heat  of  a  small 
fire  which  they  have  ultimately  extinguished,  or  after  a  head  has 
accidently  opened  without  fire.  No  system  of  automatic  shut-off 
in  a  sprinkler  head  has  yet  been  invented,  and,  when  once  opened, 
the  heads  must  continue  to  flow  until  either  the  water  supply  is 
exhausted  or  the  valves  of  the  system  are  closed  by  hand.  Cases 
have  occurred  where  a  small  fire  has  started  during  a  Saturday 
night,  in  which  the  sprinklers  soon  extinguished  the  fire,  but  the 


878 


FIRE   PREVENTION   AND   FIRE   PROTECTION 


water  continued  to  run  until  discovered  on  the  following  Monday 
morning.  A  small  fire  occurred  in  a  sprinklered  risk  in  Boston, 
not  so  many  years  ago,  where  the  first  notification  of  something 
wrong  was  the  trickling  of  water  under  the  front  door  of  the 
building,  and  thence  across  the  sidewalk,  where  it  fortunately 
attracted  the  attention  of  a  policeman,  but  not  until  the  water 
damage  had  greatly  exceeded  the  original  fire  damage. 

"Sprinkler  insurance,"  or  insurance  against  damage  resulting 
from  the  unnecessary  flow  of  water  from  sprinkler  heads,  whether 
caused  by  accidental  breakage  or  by  leakage,  is  not  unusual,  but 
companies  writing  such  insurance  make  the  alarm  valve  a  positive 
requisite. 

Accompanied  by  a  suitable  alarm  system,  —  especially  a 
central  station  supervisory  system,  —  the  automatic  sprinkler 
provides  as  nearly  an  ideal  means  of  fire  protection  as  can  prob- 
ably be  devised.  The  heads  are  ever  present  in  all  locations, 
ready  day  and  night  to  extinguish  or  check  fire  with  a  minimum 
expenditure  of  water,  while  the  alarm  system  gives  instant  noti- 
fication of  fire,  leakage  or  break  in  the  system.  However, 
neither  sprinkler  systems  as  a  whole,  nor  alarm  valves  in  particu- 
lar, are  infallible.  Both  have  their  limitations,  as  will  be  more 
fully  pointed  out  later.  The  fires  in  sprinklered  risks,  tabulated 
by  the  National  Fire  Protection  Association  for  the  year  1911, 
show  the  following  failures  of  watchman  or  automatic  alarm 
systems,  as  compared  with  sprinkler  alarms. 


Discovered 
fire. 

Failed. 

Per  cent, 
failed. 

Watchman 

66 

9 

12 

Thermostats  

8 

o 

o 

Sprinkler  alarm  

96 

5 

5 

Requirements  of  National  Board.  —  The  rules  of  the  National 
Board  of  Fire  Underwriters  require,  briefly,  an  alarm  valve  on 
every  new  automatic  sprinkler  equipment,  so  constructed  that 
the  flow  of  water  through  but  a  single  head  will  operate  a  me- 
chanical gong,  an  electric  gong,  or  both,  as  the  character  of  the 
property  or  the  circumstances  of  the  risk  may  require.  The  use 
of  both  mechanical  and  electric  gongs  is  strongly  recommended, 
as  the  use  of  the  two  principles  will  give  two  chances  of  successful 


SPRINKLER   SYSTEMS 


879 


operation  instead  of  one.  The  mechanical  gong  may  be  located 
outside  the  building  —  always  protected  from  weather  —  or  at 
any  other  desirable  place  on  the  premises!  In  cities  where  there 
is  an  alarm  company,  the  sprinkler  system  should  preferably  be 
connected  therewith,  while  in  small  towns  the  alarm  valve  may 
be  connected  with  the  public  fire  department  house.  Only  alarm 
valves  approved  by  the  underwriters  having  jurisdiction  should 
be  used. 


FIG.  365.  —  "Grinnell  Straightway  Alarm  Valve." 

Operation  of  Alarm  Valve.  —  The  several  types  of  alarm  valves 
are  apparently  quite  complicated,  but  the  best  of  them  are  really 
very  simple  in  operation.  The  simpler  they  are,  the  more  posi- 
tive their  action.  One  of  the  most  reliable  is  the  "  Grinnell 
Straightway  Alarm  Valve,"  illustrated  in  Fig.  365,  as  installed 
vertically,  the  operation  of  which  may  be  described  as  follows: 

S  is  the  pipe  leading  from  any  source  of  supply,  the  pressure  of 


880 


FIRE    PREVENTION   AND    FIRE    PROTECTION 


FIG.   366.  —  Detail  of  Alarm  Valve. 


which  may  be  variable,   as  in  public  water  mains,  where  day 
and  night  pressures  are  apt  to  vary. 

0  is  the  riser  or  supply  pipe  connecting  with  the  sprinkler 
system,  which,  when  once  filled,  is  always  under  a  constant  static 

pressure,  unless  relieved  by 
the  opening  of  one  or  more 
sprinkler  heads. 

The  problem  is,  then,  to 
introduce  at  A,  between  S  and 
0,  some  form  of  valve  which 
must  not  be  an  obstruction  to 
the  flow  of  water,  —  which 
must  be  sensitive  enough  to 
operate  under  the  least  reduc- 
tion of  the  static  pressure  in  0, 
—  and  which  will  communicate 
the  resulting  internal  flow  of 
water  in  the  .riser  to  the  outside 
of  the  valve,  where  mechani- 
cal or  electrical  alarms  may 
be  actuated.  Many  mechanical  means  of  effecting  this  com- 
munication between  inside  flow  and  outside  operation  have  been 
tried  with  little  success,  until  a  very  simple  solution  was  found, 
as  illustrated  in  Fig.  366,  wherein : 

A  is  the  shell  of  the  alarm  valve,  with  removable  cover  E. 
B  is  a  swinging  clapper,  or  check-valve,  which  can  move  up- 
ward only. 

C  is  a  renewable  valve  seat,  with  a  circular  groove  therein,  from 
one  point  in  which,  at  D,  a  pipe  leads  to  the  drip  chamber  /. 

The  groove  in  the  valve  seat  is  kept  tightly  closed  by  the  clap- 
per as  long  as  the  static  pressure  in  the  sprinkler  system  remains 
unchanged ;  but  reduction  of  the  pressure,  from  any  cause,  on  the 
upper  side  of  the  clapper,  allows  the  latter  to  lift,  upon  which, 
water  passes  through  the  groove,  thereby  actuating  a  circuit 
closer,  or  the  buckets  of  a  water  motor,  causing  an  alarm  to  be 
sounded. 

Another  requisite,  however,  is  essential  to  the  proper  operation 
of  an  alarm  valve,  viz.,  the  capacity  of  caring  for  temporary 
variations  of  water  pressure  in  the  supply  pipe  S,  which,  unless 
provided  for,  would  cause  the  operation  of  the  clapper,  and  hence 
transmit  false  alarms.  An  intermediate  "  Drip  Chamber,"  shown 


SPRINKLER    SYSTEMS 


881 


FIG.  367.  —  Detail  of  Drip 
Chamber. 


at  /  in  Fig.  365,  and  at  larger  scale  in  Fig.  367,  is,  therefore,  inter- 
posed between  the  body  of  the  valve  A  and  the  circuit  closer  M . 
This  chamber  is  so  designed  that 
the  inlet  from  the  valve  is  slightly 
larger  than  an  outlet  on  the  opposite 
side  which  is  connected  with  the 
waste  pipe  H.  This  outlet  is  closed 
by  a  valve  Z  which  is  operated,  when 
the  water  rises  to  a  height  .giving 
sufficient  pressure,  by  a  flexible  metal 
diaphragm  J,  located  in  the  bottom 
of  the  chamber.  In  the  case  of  a 
continuous  flow,  such  as  would  occur 
from  an  open  sprinkler  head  or  a 
broken  pipe,  the  drip  chamber  fills 
up,  closes  the  waste  outlet,  and  allows 
the  water  pressure  to  act  on  the 
diaphragm  of  the  circuit  closer  M, 
thus  sending  in  an  alarm.  In  the  case 
of  a  temporary  flow,  as  from  a  sud- 
den water  hammer  lifting  the  check- 
or  clapper- valve,  a  small  quantity  of  water  passes  through  into  the 
drip  chamber,  and  escapes  without  operating  the  circuit  closer. 

In  Fig.  365,  G  is  a  valve  for  draining  the  system,  Y  is  a  gate- 
valve  which  controls  the  water  supply  to  system,  K  and  L  are 
pressure  gauges,  indicating  pressures  in  sprinkler  system  and 
supply  pipe  respectively,  P  is  a  pipe  connecting  drip  chamber  to 
water  motor,  and  R  is  the  gong. 

Many  of  the  older  installations  are  not  equipped  with  alarm 
valves,  but  depend  upon  thermostats  or  watchman  service  for 
notification  of  fire. 

A  schedule  of  the  allowances  or  discounts  in  insurance  premi- 
ums for  sprinkler  protection,  as  used  by  the  Boston  Board  of  Fire 
Underwriters,  is  given  at  the  end  of  this  chapter. 

Central  Station  Supervisory  Service  is  described  in  Chapter 
XXXI. 

AUTOMATIC  DRY-PIPE  SYSTEM. 

Principles  of  Dry-pipe  System.  —  Where  buildings  or  por- 
tions of  buildings  are  so  constructed,  or  where  the  nature  of  the 
occupancy  is  such  that  the  premises  cannot  be  kept  sufficiently 


882         FIRE   PREVENTION   AND   FIRE   PROTECTION 

warm  to  prevent  the  water  from  freezing  in  the  ordinary  wet-pipe 
system,  recourse  must  be  had  to  the  dry-pipe  system,  in  which  a 
valve,  called  a  " dry- valve,"  is  introduced  in  the  supply  pipe  — 
as  at  the  base  of  riser  —  to  keep  the  water  out  of  the  piping.  The 
sprinkler  pipes  are  then  filled  with  air  under  pressure,  and  the 
reduction  of  this  air-pressure,  through  the  automatic  opening  of  a 
head  under  heat,  releases  the  " dry- valve,"  thus  allowing  the 
water  to  rush  into  the  piping  to  find  outlet  at  the  open  heads. 

Dry-pipe  vs.  Wet-pipe.  —  A  dry-pipe  system  is  not  to  be 
recommended  where  a  wet-pipe  system  can  be  used,  but  it  is  far 
preferable  to  shutting  off  entirely  the  water  supply  in  a  wet- 
system  during  cold  weather,  which  latter  practice  is  not  sanc- 
tioned by  the  National  Board  rules.  Also,  a  dry-pipe  system 
must  be  maintained  throughout  the  year  unless  specifically 
changed  by  consent  of  the  underwriters,  for  the  reason  that,  in 
making  the  change,  the  possibilities  of  trouble  due  to  sediment 
introduced  into  the  pipes  by  filling  with  water,  the  chance  of 
freezing  in  improperly  drained  pipes,  and  the  possible  wrong 
adjustment  of  the  dry-valve,  all  more  than  counterbalance  the 
benefits  of 'a  wet-pipe  system  while  it  exists,  even  making  allow- 
ances for  the  tightening  of  the  joints  through  the  effects  of  rust 
and  sediment  from  the  presence  of  water,  and  the  consequent 
improved  air-tight  qualities  which  would  follow  when  returned 
to  a  dry  system. 

Special  attention  has  been  drawn  by  manufacturers  to  the 
desirability  of  using  calcium  chloride  solution  in  automatic  sprink- 
ler systems  where  installed  in  warehouses  and  other  places  of 
extreme  exposure  during  the  winter  months.  They  state  that 
the  use  of  calcium  chloride  does  away  with  the  necessity  of  main- 
taining a  dry-pipe  system  with  the  extra  cost  of  installation  and 
the  attending  risk  of  disarrangement  by  leakage  of  water  into  the 
system  through  defective  valves  or  through  a  failure  of  the  air 
supply.  For  this  purpose  they  recommend  that  the  system  be 
filled  with  calcium  chloride  solution  of  1.225  or  1.250  specific 
gravity,  and  a  check-valve  installed  to  separate  this  from  the 
source  of  water  supply.* 

Disadvantages  of  Dry-pipe  Systems.  —  Wet  systems  are 
preferable  to  dry  systems  on  account  of  the  necessary  introduc- 
tion of  the  "dry-valve,"  which,  like  all  other  automatic  arrange- 

*  See  "Freezing  Preventives  for  Water  Pails  and  Chemical  Extinguishers," 
by  J.  Albert  Robinson  in  National  Fire  Protection  Association's  "Quarterly," 
January,  1912.  . 


SPRINKLER    SYSTEMS  883 

ments,  is  subject  to  failure  at  critical  times,  no  matter  how 
perfectly  conceived,  —  and  also  on  account  of  the  precious  time 
which  must  elapse  during  the  opening  of -the  head,  the  release  of 
the  valve,  and  the  filling  of  the  pipes  by  water. 

It  can  be  seen  that  some  time  is  taken  by  these  operations, 
which  is  limited  by  the  rule  that  not  over  400  heads  shall  be  placed 
on  one  dry-valve,  and  is  also  dependent  upon  the  releasing  point 
of  the  particular  type  of  dry-valve,  and  the  air-  and  water-pres- 
sure which  may  chance  to  obtain  at  the  time  of  fire.  Under 
average  conditions,  this  period  will  vary  from  1  to  2  minutes. 
The  nearer  the  valve  is  located  to  base  of  riser,  the  less  large 
piping  there  is  under  air-pressure  and  the  quicker  is  the  opera- 
tion.* 

Where  exposed  to  cold  weather,  dry-pipe  valves  must  always 
be  enclosed  in  insulated  pits  or  closets,  heated  by  steam,  lantern, 
or  approved  electric  heater,  to  prevent  freezing.  A  2-inch  test 
pipe  should  also  be  placed  immediately  under  each  dry-pipe  valve 
in  order  that  the  presence  of  water  up  to  the  valve  may  be 
determined  at  any  time. 

Installation  of  Dry-pipe  System.  —  The  same  rules  regard- 
ing the  spacing  of  sprinkler  heads  and  the  size  of  piping,  etc.,  are 
used  for  dry-pipe  system  as  for  wet-pipe,  except  that  the  number 
of  sprinkler  heads  controlled  by  any  one  dry-pipe  valve  should 
not  exceed  400,  and  preferably  not  over  300.  This  is  in  order 
that  those  sprinkler  heads  farthest  away  from  the  dry-valve  may 
still  discharge  water  within  a  reasonable  period  after  the  release 
of  the  air  pressure,  for  manifestly  the  time  lost  between  the  fusing 
of  any  sprinkler  heads,  especially  those  at  or  near  the  ends  of 
branch  lines,  and  the  automatic  operation  of  the  dry-valve,  is 
dependent  upon  the  number  of  sprinkler  heads,  the  length  and 
number  of  the  branch  lines,  and  the  size  of  piping.  The  National 
Board  rules,  therefore,  recommend  not  over  300  sprinklers  being 
dependent  upon  one  dry-pipe  valve,  and,  where  practicable,  even 
a  smaller  number  is  to  be  preferred,  say  not  over  200  or  250  heads. 
In  a  large  risk  the  system  should  preferably  be  divided  horizontally 
by  floors,  providing  separate  valves  for  each  two  or  three  floors;  or, 
the  system  can  be  divided  into  several  vertical  risers  so  as  to  keep 
not  over  the  maximum  number  of  heads  for  each  valve. 

Air  Pressure.  —  For  providing  air  pressure  in  the  piping,  the 
air  compressor  pump  should  be  of  sufficient  capacity  to  increase 

*  See  "Handbook  of  Fire  Protection  for  Improved  Risks,"  Crosby  and  Fiske. 


884         FIRE    PREVENTION   AND    FIRE    PROTECTION 

the  air  pressure  not  less  than  one  pound  per  two  minutes  of  pump- 
ing, or  preferably  faster.  Steam  or  electric  pumps  are  to  be  pre- 
ferred, and  the  air  supply  should  be  taken  through  a  protective 
screen  from  outside  source,  or  from  a  room  having  dry  air,  in  order 
that  as  little  moisture  as  possible  be  taken  into  the  system. 

OPEN  SPRINKLERS. 

Use  of.  —  Open  sprinklers  are  intended  to  provide  somewhat 
the  same  kind  of  protection  for  a  building's  exterior  as  automatic 
wet  and  dry-pipe  systems  do  for  the  building's  interior  or  contents, 
i.e.,  by  insuring  the  prompt  presence  of  water,  and  its  most  eco- 
nomical and  effective  distribution,  at  needed  points. 

Installation  of.  —  Open  sprinkler  systems  contain  no  auto- 
matic heads  or  alarm  valves,  consequently  they  are  entirely  de- 
pendent upon  human  control.  They  do,  however,  constitute  a 
valuable  means  for  coping  with  exposure  hazard,  and  this  is  ac- 
complished through  the  presence  of  special  sprinkler  heads  which 
are  always  open,  and  which  are  distributed  at  exterior  cornices, 
eaves,  over  windows,  and  on  mansard  or  peaked  roofs,  etc.  These 
heads  are  connected  by  piping,  —  either  within  or  without  the 
building,  —  which  is  capable  of  being  filled  at  short  notice  either 
from  some  constant  source  of  supply,  regulated  by  hand  valve,  or 
from  sidewalk  connections  with  steam  fire  engines.  Such  a  dis- 
tribution of  water  at  vulnerable  points  is  most  valuable  in  case 
of  serious  exposure  fire  in  adjacent  or  opposite  neighbors,  as  the 
resulting  flow  of  water  is  much  more  effectively  distributed  than 
is  the  water  from  hose  streams. 

Types  of  Heads.  —  Many  different  types  of  window,  cornice 
and  ridge-pole  sprinkler  heads  have  been  patented,  but  few  have 
had  any  extended  use.  In  fact,  the  whole  scheme  of  open  sprin- 
klers has  not  been  developed  comparably  to  inside  automatic 
sprinklers. 

Heads  should  be  designed  to  accomplish  specific  work  in  specific 
locations.  In  a  window  sprinkler  head  the  object  should  be  to 
flood  the  opening  and  trim  as  evenly  as  possible.  For  a  cornice 
sprinkler  the  water  usually  requires  to  be  thrown  upward  for  some 
distance  —  so  as  to  wet  thoroughly  the  face  and  under  side  of 
cornice  —  as  well  as  laterally,  to  give  side  distribution  over  wall 
areas.  Most  of  the  sprinkler  companies  use  the  same  type  of 
heads  for  both  window  and  cornice  protection,  while  for  ridge-pole 


SPRINKLER    SYSTEMS 


885 


sprinkler  heads  —  as  at  the  peak  of  combustible  roofs  — -•  they  use 

their  standard  automatic  head,  but  open,  without  valve  or  strut. 

Fig.  368  illustrates  the  Grinnell  window  sprinkler  at  full  size. 

The  Grinnell  cornice  sprinkler  and  the  International  eave  sprinkler 


FIG.   368.  —  "Grinnell"  Window 
Sprinkler. 


FIG.  369.  —  "Grinnell"  Cornice 
Sprinkler. 


are  shown  in  Figs.  369  and  370  respectively,  at  full  size.  These 
are  placed  on  the  under  side  of  the  piping  which  runs  along  below 
the  cornice,  with  the  shovel-shaped  deflectors  turned  toward  the 
building.  Fig.  371  shows  a  ridge-pole  sprinkler  head  at  one-fourth 


FIG.  370.  —  "  International ' '  Eave  Sprinkler.    FIG.  371.  —  Ridge-pole  Sprinkler. 

size.     These  are  placed  upright  on  the  supply  pipe  which  is  placed 
about  six  inches  above  the  ridge  of  roof. 


886 


FIRE    PREVENTION   AND    FIRE    PROTECTION 


Location  and  Number  of  Heads.  —  Where  used  on  non- 
fire-resisting  buildings,  especially  those  of  exterior  wooden  con- 
struction, it  is  desirable  to  place  the  heads  in  such  locations  and 
numbers  as  to  insure  a  thorough  wetting-down  of  all  cornices  and 
wall  surfaces,  including  heads  over  all  windows,  or  at  least  over 
each  vertical  row  of  windows.  On  brick  or  fire-resisting  buildings 
the  necessity  for  wetting  the  brickwork  does  not  exist,  but  the 
heads  should  be  arranged  over  each  window  in  vertical  rows  in 
such  manner  as  to  flood  the  casings  and  glass  of  the  openings. 

For  windows  not  over  five  feet  wide,  one  sprinkler  should  be 
placed  at  the  center  of  the  window  head,  so  that  the  water  dis- 
charge therefrom  will  thoroughly  wet  the  upper  part  of  window, 
and,  by  running  down  over  sash  and  glass,  wet  the  entire  window 
to  the  greatest  possible  extent.  For  windows  over  five  feet  wide, 
or  where  mullions  divide  the  window  areas  into  separate  bays, 
two  or  more  heads  must  be  used,  as  required  by  the  Under- 
writers. 

Discharge  Orifice.  —  Where  but  one  horizontal  line  of  win- 
dow or  cornice  sprinklers  is  used  —  as,  for  instance,  at  the  cornice 
line  of  a  two-  or  three-storied  building  —  each  head  must  have  a 
smooth-bore  tapering  outlet  with  an  unobstructed  f -inch  diameter 
orifice.  Where  more  than  one  line  is  used,  the  following  size 
orifices  in  inches  must  be  followed. 


Two 
lines. 

Three 
lines. 

Four 
lines. 

Five 

lines. 

Six 
lines. 

Top  line  

| 

f 

| 

3 

•g 

, 

Next  lower  
Next  lower 

A 

4 

f 

X 

1 

3 

8 

Next  lower  

i 

A 

A 

Next  lower 

i 

T! 

Next  lower 

i 

Where  over  six  lines  are  used,  the  sizes  of  orifices  are  at  the 
option  of  the  underwriters  having  jurisdiction,  and  in  this  case 
it  may  be  preferable  to  omit  sprinklers  on  the  first  story,  or  pos- 
sibly even  on  the  second  story;  but  if  over  six  lines  are  used,  the 
system  should  be  divided  horizontally,  with  independent  risers  for 
different  stories.  Thus  where  eight  lines  would  be  required,  the 
upper  four  lines  should  be  on  one  riser,  with  orifices  as  per  table 


SPRINKLER    SYSTEMS 


887 


above,  while  the  lower  four  lines  would  be  similarly  arranged  on 
another  riser. 

Pipe  Sizes.  —  The  National  Board  requirements  as  to  sizes  of 
piping  —  or  branch  lines  —  and  as  to  feed  mains  or  risers,  will 
practically  determine  the  arrangement  of  the  system. 


FIG.  372.  —  Central  Riser  Installation  of  Open  Sprinklers. 

Thus  where  a  central  riser  is  used,  no  branch  line  should  supply 
more  than  six  heads.  Fig.  372  shows  a  central  riser  installation 
with  two  horizontal  lines  of  heads.  Where  the  "  gridiron  ' '  system 


en    EH    B3 ' 


FIG.  373.  —  "Gridiron"  Arrangement  of  Open  Sprinklers. 


is  used  —  i.e.,  with  two  or  more  vertical  feed  risers  connected  by 
horizontal  piping  —  the  lines  between  risers  must  not  supply 
more  than  twelve  heads.  Fig.  373  illustrates  the  gridiron  arrange- 
ment. 


888         FIRE    PREVENTION    AND    FIRE    PROTECTION 


The  sizes  of  horizontal  piping  in  either  central  riser  or  gridiron 
system  must  be  in  accordance  with  the  following  schedule: 


f-inch  orifice. 

iVinch  orifice. 

j-inch  orifice. 

One  head  
Two  heads 

f-iri.  pipe 
1-in.  pipe 

f-in.  pipe 

f-in.  pipe 

Three  heads  
Four  heads  

l}-in.  pipe 

1-in.  pipe 

Five  heads 

1-in   pipe 

Six  heads  

H-in.  pipe 

li-in.  pipe 

IJ-in.  pipe 

N.B.  —  In  the  gridiron  system  the  end  head  is  considered  as 
being  the  one  directly  in  the  center  if  the  number  is  odd,  or  on 
either  side  of  the  center  if  the  number  is  even. 

Risers  and  Feed  Mains.  —  The  sizes  of  central  feed  risers 
must  be  as  follows: 

IJ-in.  not  over    6  heads  3-in.  not  over  36  heads 

2-in.  not  over  10  heads  3i-in.  not  over  55  heads 

2%-m.  not  over  20  heads  4-in.  not  over  72  heads 

For  gridiron  side  feed  risers,  use  the  same  size  schedule,  counting 
to  the  center  of  each  line.  If  the  number  of  heads  on  line  is  odd, 
the  center  head  may  be  neglected  in  figuring  the  size  of  side  risers, 
but  supply  pipe  feeding  risers  must  be  figured  for  all  heads  sup- 
plied. Also  where  feed  main,  including  risers  to  the  first  branch 
line,  is  over  25  feet  in  length,,  such  feed  main  must  be  at  least  a 
size  larger  than  required  by  schedule. 

Valves.  —  Each  central  feed  riser  must  have  a  controlling  valve 
of  approved  type,  located  at  some  accessible  point,  preferably  in 
first  story.  Where  side  feed  risers  are  used,  they  must  be  con- 
nected together  at  the  bottom  and  have  one  valve  so  located  as 
to  control  both  risers. 

Water  Supply.  —  The  water  supply  may  be  from  city  water 
mains,  standpipe,  pump,  or  steamer  connection,  but  never  from 
any  pressure  or  gravity  tank  used  to  supply  automatic  sprinklers 
unless  additional  capacity  is  especially  provided.  Water  supply 
should  be  of  sufficient  capacity  to  feed  all  heads  designed  to  be 
operated  at  one  time,  and  to  maintain  not  less  than  10  pounds 
pressure  at  top  of  riser  for  not  less  than  one  hour.  Steamer  con- 
nections should  be  located  at  points  protected  from  severe  exposure. 


SPRINKLER    SYSTEMS  889 

Window  Protection.  —  The  protection  of  window  areas 
against  external  attack  by  fire  is  confessedly  one  of  the  most 
important,  and  at  the  same  time  one  of  the  most  difficult  problems 
in  fire  protection.  The  necessity  for  some  adequate  protection 
has  been  emphasized  by  every  large  conflagration  since  fire  pre- 
vention has  become  a  science,  and  reports  and  digests  on  the 
Paterson,  Baltimore  and  San  Francisco  fires,  besides  scores  of 
others,  have  all  contained  pointed  reference  and  recommendations 
regarding  the  necessity  for  improvement  in  this  direction.*  The 
importance  of  window  protection,  especially  under  conflagration 
conditions,  is  only  too  obvious,  and  if  our  serious  conflagrations 
have  done  nothing  more,  they  have  certainly  served  to  awaken 
some  adequate  sense  of  the  necessity  for  such  measures. 

Standard  tin-covered,  folding  iron,  and  rolling  shutters  have 
all  given  good  accounts  of  themselves  in  moderate  fires,  but,  gen- 
erally speaking,  these  types  will  not  develop  positive  fire-resistance 
under  conflagration  conditions  on  account  of  their  tendency  to 
warp  or  wilt,  unless  cooled  upon  one  side  by  the  application  of 
water. 

Wire  glass  windows,  in  suitable  metal  frames,  constitute  by  far 
the  least  objectionable  appearing  device  for  the  protection  of 
openings  under  moderate  exposure.  Such  windows  will  prevent 
the  direct  passage  of  flame,  but  the  great  radiation  of  heat  through 
the  glass  still  leaves  a  decided  hazard  to  be  cared  for. 

The  use  of  open  sprinklers,  therefore,  may  be  made  to  serve  as 
a  valuable  adjunct  to  any  type  of  window  protection,  and  there 
is  little  doubt  that  their  installation  will  become  more  frequent 
and  better  appreciated.  They  will  prove  a  valuable  reinforce- 
ment to  the  standard  tin-covered  shutter  under  severe  conditions, 
they  will  serve  to  keep  rolling  shutters  wet  and  hence  insure  utmost 
efficiency,  while  they  will  also  greatly  decrease  the  radiation  of 
heat  through  wire  glass.  Even  if  used  alone  for  moderate  ex- 
posure, without  any  of  the  usual  types  of  window  protection  men- 
tioned above,  open  sprinklers  will  still  provide  a  fairly  efficient 
protection  by  means  of  the  water  blanket  supplied  by  their  use. 

The  system  of  open  sprinklers  has  its  strong  advocates,  and  also 
its  opponents  —  the  latter  usually  advancing  the  fear  that  too 
great  reliance  will  be  placed  upon  the  sprinklers  alone,  instead  of 
looking  upon  them  as  an  economical  and  efficient  reinforcement 
to  some  other  type  of  protection. 

*  See  Chapter  XIV. 


890         FIRE   PREVENTION   AND   FIRE    PROTECTION 

No  system  of  open  sprinklers  is  a  positive  check  against  severe 
exposure  fire  in  the  same  sense  as  are,  for  instance,  standard  shut- 
ters; and  the  fact  that  at  best  they  are  only  a  partial  barrier 
should  be  thoroughly  understood.  They  are  not  in  the  same 
class  as  shutters  or  wire  glass  windows.  With  this  fact  clearly 
in  mind,  namely,  that  in  no  sense  can  open  sprinklers  be  classed 
as  alternatives  with  wire  glass  windows  or  shutters,  they  can  be 
given  credit  as  a  valuable  aid  in  protecting  against  exposure  fires, 
and  their  use  should  be  encouraged.  They  can  often  be  used  to 
great  advantage  where  it  is  not  feasible  to  install  standard  shut- 
ters, or  as  an  aid  to  steel  rolling  shutters,  or  for  light  to  moderate 
exposure,  such  as  street  fronts  where  the  cost  of  shutters  or  wired 
glass  might  be  considered  prohibitive.* 

Actual  Tests  of  Open  Sprinklers.  —  In  report  No.  XIII  of 
the  Boston  Insurance  Engineering  Experiment  Station,!  dealing 
with  the  Baltimore  conflagration,  may  be  found  these  references 
to  open  sprinklers: 

It  will  be  observed  that  a  large  building,  protected  by  auto- 
matic sprinklers  both  within  and  without,  suffered  very  little  and 
was  doubtless  protected  in  large  measure  by  these  safeguards. 
This  immunity  from  loss  may  doubtless  be  in  part  credited  to  the 
sprinkler  protection;  it  would  have  been  wholly  credited  had 
not  the  wind  changed  at  a  critical  time,  turning  aside  the  extreme 
danger  to  which  this  building  would  otherwise  have  been  subjected. 

Outside  or  eave  sprinklers  are  of  special  value  in  prevent- 
ing the  spread  of  fire  from  building  to  building.  This  fact  was 
fairly  demonstrated  at  the  O'Neil  Building  in  Baltimore,  yet  more 
fully  in  the  Kilgour  Building  ill  Toronto,  in  the  Mohair  Plush 
Building  in  Lowell  and  in  the  American  Bicycle  Company's  Build- 
ing in  North  Milwaukee.  The  latter  two  buildings  escaped  with- 
out damage,  when  without  eave  sprinklers  they  would  probably 
have  suffered  a  heavy  loss,  if  not  total  destruction. 

A  test  of  the  value  of  open  sprinklers  for  window  protection  was 
afforded  in  the  Utica,  N.  Y.,  conflagration  of  May  10,  1905.  At 
the  rear  of  a  large  department  store,  which  was  entirely  destroyed, 
was  the  Utica  Manual  Training  School. 

Twelve  large  windows  faced  the  fire  at  an  average  distance 
of  25  feet  (the  shortest  distance  being  23  feet).  These  windows 
were  protected  by  six  outside  sprinklers  and  not  even  a  light  of 
glass  was  cracked. 

It  was  the  general  opinion  of  all  that  these  sprinklers  saved 
this  building  from  destruction.  It  was  impossible  to  put  shutters 
on  these  windows  on  account  of  the  very  small  size  of  the  piers 
between  them,  and  the  sprinklers  were  erected  as  a  substitute. J 

*  "Handbook  of  Fire  Protection  for  Improved  Risks,"  Crosby  and  Fiske. 
t  By  Prof.  Charles  E.  Norton  and  Mr.  Edward  Atkinson. 
%  See  Insurance  Engineering,  May,  1905,  page  482, 


SPRINKLER   SYSTEMS 


891 


Use  in  Mercantile  Buildings.  —  Many  mercantile  buildings, 
especially  stores  and  manufacturing  buildings  located  in  the  con- 
gested areas  of  large  cities,  are 
now  equipped  with  open  win- 
dow sprinklers.  A  typical  span- 
drel section  of  the  fire-resisting 
Siegel  department  store  (built 
in  Boston  in  1906),  showing  the 
location  of  a  window  sprinkler 
head,  is  illustrated  in  Fig.  374. 
Open  window  sprinklers  must, 
of  course,  be  placed  on  an  en- 
tirely separate  system  of  piping, 
risers,  etc.,  from  inside  wet  or 
dry  sprinklers. 

For  further  information  con- 
cerning open  sprinklers,  espe- 
cially as  actually  applied  to 
many  mercantile  buildings,  see 
illustrated  article  "  Outside 


AVindow 


FIG.   374.  —  Open   Sprinkler    Heads, 
Siegel  Store,  Boston. 


Sprinklers   as   a   Protection    against   Exposure,"   by   Henry   A. 
Fiske,  in  Insurance  Engineering,  March,  1905. 


BASEMENT  SPRINKLERS. 

Principle  of.  —  Basement,  or  perforated  sprinklers,  constitute 
a  variation  of  the  open  sprinkler,  applied  to  the  protection  of 
basements  or  other  floors  below  the  street  level,  where  conditions 
render  hose  or  nozzle  work  impossible.  Instead  of  heads  at  cer- 
tain fixed  points  for  the  distribution  of  water,  basement  sprinklers 
consist  of  piping  (suspended  from  the  ceilings)  which  is  perforated 
with  open  holes  at  frequent  intervals  and  connected  with  a  steamer 
connection  at  the  sidewalk  level. 

The  waste  of  water  in  perforated  sprinklers  is,  of  course,  far 
greater  than  in  automatic  or  dry-pipe  sprinklers,  and  is  probably 
equal  to  or  even  greater  than  the  waste  in  open  or  external  sprin- 
klers —  with  the  added  disadvantage  that  the  continuously  per- 
forated pipes  discharge  water  at  random  over  their  entire  length 
and  over  stock  and  contents  regardless  of  the  actual  location  of 
the  seat  of  the  fire.  But,  at  the  same  time,  the  perforated  sprin- 
kler often  accomplishes  promptly  what  the  firemen  cannot  do  with- 


892         FIRE    PREVENTION    AND    FIRE    PROTECTION 

out  grave  danger  and  serious  delay,  namely,  the  extinguishment 
of  a  serious  basement  fire  with  its  usual  accompaniment  of  dense 
and  overpowering  smoke. 

Increasing  Number  of  Sub-cellars.  —  The  great  changes 
which  took  place  in  building  construction  through  the  introduc- 
tion of  steel  skeleton  construction  also  served  to  present  new  and 
serious  problems  of  fire  protection,  particularly  in  regard  to  the 
vertical  extension  of  office  and  commercial  buildings,  both  upward, 
as  in  structures  of  immoderate  height,  and  downward,  as  in  those 
cases  where  sub-cellars  and  even  sub-sub-cellars  have  been  intro-  • 
duced.  These  new  problems,  and  their  relation  to  fire  depart- 
ment work,  are  more  fully  discussed  in  other  chapters  treating  of 
standpipes,  hose-reels  and  other  auxiliary  appliances  which  have 
come  into  being  under  the  new  conditions,  but  it  is  pertinent  to  a 
discussion  of  basement  sprinklers  to  remark  that  that  system  is 
also  an  outgrowth,  in  a  great  measure,  of  the  new  circumstances 
which  had  to  be  met. 

Dangers  of  Basement  Fires.  —  To  all  those  who  live  in  large 
cities,  the  spectacle  of  the  long  and  trying  fight  between  the  fire 
department  and  a  serious  basement  or  cellar  fire  is  familiar. 
Many  such  fires  have  occurred  in  New  York  and  other  large 
cities  where  many  firemen  have  succumbed  to  the  effects  of  the 
overpowering  smoke  in  either  attempting  to  fight  the  fire  at  close 
range  or  to  rescue  those  comrades  who  had  fallen  at  the  foot  of 
stairs  or  ladders  leading  to  the  smoke-charged  basement.  An 
entire  engine  company  has  been  so  disabled  in  New  York. 

Frequency  of  Basement  Fires.  —  That  fires  originating  in 
basement  or  underground  areas  are  more  frequent  and  more 
severe  than  is  popularly  supposed  is  shown  by  the  fire  record  in 
New  York  City,  where,  during  the  period  covered  by  the  years 
1896  to  1905,  both  inclusive,  50  such  fires  occurred,  an  average  of 
5  per  year,  with  a  total  loss  of  $8,460,014,  or  an  average  loss  per 
year  of  $846,001  and  an  average  loss  per  fire  of  $169,200. 

Basement  Sprinklers  from  the  Fireman's  Standpoint.  — 
Chief  of  Battalion  William  T.  Beggin,  formerly  in  charge  of  the 
Bureau  of  Violations  and  Auxiliary  Fire  Appliances  of  the  New 
York  Fire  Department,  thus  summarizes  the  dangers  of  cellar  fires 
from  the  fireman's  standpoint: 

On  an  upper  floor  it  is  generally  possible  to  provide  some 
ventilation  so  as  to  relieve  a  smoke-charged  atmosphere  to  the 
extent  that  men  can  live  in  it  long  enough  to  get  water  on  the 


SPRINKLER   SYSTEMS  893 

fire,  but  the  underground  floor  rarely  offers  'any  opportunities  of 
ventilation.  To  send  men  down  into  a  cellar  is  not  only  to  dan- 
gerously overtax  their  physical  organism 'but  also  to  risk  their 
lives,  for,  if  overcome,  they  may  fall  out  of  sight  of  their  comrades, 
and  in  the  effort  to  rescue  them  others  may  be  sacrificed.  Under 
any  circumstances  men  can  work  only  for  a  short  time  in  a  smoke- 
charged  atmosphere,  and  they  even  then  suffer  from  the  effects 
of  it  for  some  days.  The  disabling  of  men  explains  the  sending 
of  extra  alarms  for  cellar  fires;  it  is  necessary  not  only  to  have 
additional  men  to  relieve  those  incapacitated  but  also  to  perform 
the  extra  work  required  to  extinguish  such  fires.  In  accordance 
with  the  established  custom  of  entering  buildings  and  fighting 
fires  at  close  quarters,  an  attempt  is  always  made  to  reach  the 
cellars  by  the  usual  means  of  access,  such  as  stairways,  elevators 
or  other  shafts,  but,  as  a  rule,  conditions  make  this  physically 
impossible,  and  it  becomes  necessary  then  to  make  openings 
wherever  possible  in  order  to  carry  off  the  smoke.  If  there  are 
sidewalk  lights,  these  are  broken  open,  holes  are  cut  in  the  floors, 
and  all  possible  outlets  are  provided  for  the  escape  of  smoke. 
Into  these  openings  are  put  cellar  and  sub-cellar  pipes  and  dis- 
tributing nozzles,  which  discharge  water  in  a  circle,  but  this  is 
working  at  random,  for  it  is  usually  difficult  to  locate  the  fire  or 
to  bring  the  cellar  pipes  to  bear  on  it.  A  cellar  belching  forth 
smoke  and  gas  like  an  active  volcano  is  beyond  human  endurance 
at  close  quarters,  and  there  is  nothing  left  but  to  turn  the  lines 
into  it  and  drown  out  the  fire.  This  means  not  only  water- 
soaking  all  the  contents  in  the  sub-cellar  but  in  the  cellar  as  well; 
it  possibly  means  the  spreading  of  the  water  through  the  founda- 
tion walls  into  the  adjoining  cellars  or  down  into  the  soil  and 
under  the  walls,  with  consequent  water  damage  in  other  prem- 
ises; it  means  excessive  smoke  damage  throughout  the  upper 
floors;  it  means  a  chance  of  the  fire  getting  such  headway  that 
all  the  efforts  of  the  firemen  cannot  confine  it  to  the  underground 
floors ;  and  it  means  an  extra  tax  on  the  men  and  apparatus,  with 
the  result  of  reducing  the  protection  for  other  districts.  The 
damage  from  cellar  fires  is  indicated  by  the  record  of  prominent 
fires  which  originated  in  such  places  and  extended  throughout 
the  building.* 

Basement  Sprinklers  from  the  Insurance  Standpoint.  — 

Insurance  interests  generally  do  not  look  with  favor  on  the  em- 
ployment of  perforated  sprinklers,  for  the  reason  that,  when  util- 
ized, such  basement  sprinkler  pipes  discharge  water  copiously 
from  the  entire  system,  regardless  of  the  extent  of  the  actual  fire, 
thus  often  resulting  in  a  disproportionately  large  water  damage. 

The  use  of  perforated  pipe  systems  should  be  prohibited,  as 
such  systems  are  unreliable,  inefficient  and  liable  to  result  in 
water  damages  wholly  disproportionate  to  the  extent  of  fire. 

*  See  Journal  of  Fire,  August,  1906. 


894         FIRE    PREVENTION    AND    FIRE    PROTECTION 

Where  it  is  desirable  to  protect  only  a  part  of  a  building,  a  system 
of  automatic  sprinklers  with  adequate  water  supply  should  be 
employed  and  the  portions  protected  plainly  marked  at  the 
Siamese  steamer  connections  on  the  outside  of  the  building.* 

New  York  City  Law  regarding  Basement  Protection.  — 

It  was  partially  to  meet  the  new  conditions  of  building  construc- 
tion previously  mentioned  that  the  Greater  New  York  charter 
(Section  762)  provided  that  the  owners  or  proprietors  of  practically 
every  class  of  building  (save  private  residences)  should  "  provide 
such  means  of  communicating  alarms  of  fire,  accident  or  danger, 
to  the  police  and  fire  department,  respectively,  as  the  fire  com- 
missioner or  police  board  may  direct;  and  shall  also  provide  such 
fire  hose,  fire  extinguishers,  buckets,  axes,  fire-hooks,  fire-doors  and 
other  means  of  preventing  and  extinguishing  fires  as  said  fire  com- 
missioner may  direct.''  The  equipment  of  cellars  with  fire  extin- 
guishing appliances  is  also  called  for  by  Section  102  of  the  New 
York  Building  code,  which  requires  the  following  under  "  Auxiliary 
Fire  Apparatus  for  Buildings:" 

In  such  buildings  as  are  used  or  occupied  for  business  or 
manufacturing  purposes  there  shall  be  provided,  in  connection 
with  said  stand-pipe  or  pipes,  one  and  one-half  inch  perforated 
iron  pipes  placed  on  and  along  the  ceiling  line  of  each  floor  below 
the  first  floor  and  extending  to  the  full  depth  of  the  building. 
Such  perforated  pipe  shall  be  provided  with  a  valve  placed  at  or 
near  the  standpipe,  so  that  the  water  can  be  let  into  same  when 
deemed  necessary  by  the  firemen,  or  in  lieu  of  such  perforated 
pipes,  automatic  sprinklers  may  be  put  in. 

Under  the  previously  quoted  authority  of  the  Greater  New  York 
charter,  these  requirements  as  to  basement  protection  have  been 
actively  enforced  by  the  New  York  Fire  Department,  through  its 
Bureau  of  Violations  and  Auxiliary  Fire  Appliances;  and  a 'great 
number  of  premises  have  been  so  equipped  under  compulsory 
orders,  mostly  with  perforated  pipes,  but  other  premises  with 
automatic  sprinklers. 

New  York  Fire  Department  Regulations.  —  The  New  York 
Fire  Department  regulations  as  to  perforated  pipes  in  cellars  or 
sub-cellars  are  as  follows: 

All  perforated  pipes  to  be  of  wrought-iron  or  steel,  and 
capable  of  withstanding  a  pressure  of  300  pounds  to  the  square 

*  Report  of  W.  C.  Robinson,  Chief  Engineer,  Underwriters'  Laboratories, 
on  Fire  in  Parker  Building. 


SPRINKLER    SYSTEMS  895 

inch.  They  shall  be  suspended  with  proper  hangers,  not  less 
than  6  inches  below  the  ceiling  and  parallel  thereto,  running  full 
depth  of  building,  and  placed  12 J  feet  apart  on  centers,  and  6  feet 
from  side  walls,  securely  fastened  and  properly  braced  to  with- 
stand vibration.  The  pipes  must  be  1J  inches  internal  diameter, 
perforated  with  1-16  inch  drilled  holes,  holes  to  be  on  the  quar- 
ters, or  45  degree  lines,  2  inches  apart  longitudinally,  and  stag- 
gered, thus  making  24  holes  per  running  foot  of  pipe.  These 
IJ-inch  pipes  to  be  connected  with  a  feed-pipe  4  inches  internal 
diameter,  placed  close  to  and  parallel  to  front  or  side  walls  of 
building,  and  connected  by  and  with  a  4-inch  pipe  terminating 
outside  of  said  wall  in  a  3-inch  Siamese  connection  which  must 
be  fitted  with  proper  clapper  valve  or  valves;  one  Siamese  con- 
nection to  furnish  water  to  no  more  than  a  total  of  400  feet  of 
perforated  pipe,  and  no  single  line  to  be  longer  than  100  feet. 
Sub-cellars  to  have  separate  equipment. 

A  suitable  iron  plate  on  outside  of  building,  with  raised 
letters,  must  be  fastened  to  the  wall-  or  other  approved  place  near 
cellar  connection,  to  read  "To  PERFORATED  PIPES  IN  CELLAR." 
Sign  for  sub-cellar  to  read  "To  PERFORATED  PILES  IN  SUB-CEL- 
LAR." 


EFFICIENCY  OF  SPRINKLERS:   STATISTICS. 

Turning,  now,  to  a  consideration  of  the  efficiency  or  failure  of 
sprinkler  protection,  some  statistics  will  be  given  demonstrating 
the  former,  and  some  fires  described  briefly  which  will  illustrate 
the  latter.  From  these  two  viewpoints,  the  value  of  sprinkler 
protection  and  its  weaknesses  may  be  pretty  accurately  deter- 
mined. 

Boston  Manufacturers'  Mutual  Fire  Insurance  Com- 
pany. —  This  is  the  mutual  fire  insurance  company  —  making 
a  specialty  of  sprinklered  mill  and  factory  risks  —  of  which  the 
late  Edward  Atkinson  was  president.  From  their  report  for  the 
year  ending  December  31,  1911,  it  appears  that  the  amount  at 
risk  on  that  date  was  $357,691,997.00.  For  the  fifteen  years  from 
January  1,  1897,  to  January  1,  1912,  the  risks  written  amounted 
to  $3,302,812,120.00,  on  which  the  average  loss  per  hundred  dollars 
was  3.52  cents.  The  annual  cost  of  insurance  on  policies  ter- 
minated in  that  period  was  6.55  cents  per  hundred  dollars. 

The  total  number  of  claims  for  losses  in  the  year  1911  amounted 
to  499,  at  an  average  loss  per  claim  of  $162.88,  or  a  loss  ratio  of 
2.32  cents  per  hundred  dollars  insured. 

The  Effect  of  Sprinkler  Protection  upon  the  Loss  Ratio  is  shown  in 
tabular  form  as  follows: 


896 


FIRE    PREVENTION   AND    FIRE    PROTECTION 


Years. 

Amount. 

Losses. 

Rate  of  loss 
to  amount 
written, 
per  $100. 

1850-1875  incl  
1876-1895  incl  
1896-1911  incl. 

$406,284,084 
1,551,259,471 
3,416,225,184 

$1,027,536.98 
2,809,203.32 
1,241,062  36 

$0  2529 
0.1810 
0  0363 

61  years  =  .  .  .  . 

$5,373,768,739 

$5,077,802.66 

$0.0944 

The  years  1850-1875,  inclusive,  represent  the  period  during  which 
the  mills,  etc.,  at  risk  were  unequipped  with  automatic  sprin- 
klers, —  the  years  1876-1895,  inclusive,  the  period  during  which 
plants  were  being  equipped  with  sprinklers,  —  and  the  years 
1896-1911,  inclusive,  the  period  when  risks  were  fully  equipped 
with  sprinklers. 

The  constant  improvement  year  by  year  in  matters  of  construc- 
tion, fire  protection  equipment,  inspection  and  maintenance  have 
naturally  greatly  decreased  the  cost  of  insurance.  Thus  the 
average  annual  cost  of  $100  insurance,  divided  into  ten  year 
periods,  has  been : 


1850-1860, 
1861-1870, 
1871-1880, 
1881-1890, 
1891-1900, 
1901-1910, 


10J  years,  $0.4373 
10  years,  0.2795 
10  years,  0.2538 
10  years,  0.2271 
10  years,  0.1436 
10  years,  0.0676 


This  record  speaks  for  itself. 

Boston  Sprinkler  Fires.  —  During  the  year  ending  October 
31,  1906,  thirty  fires  in  sprinklered  risks  occurred  in  the  city  of 
Boston,  causing  an  aggregate  loss  of  $5722,  or  an  average  of  $190 
each,  the  maximum  loss  being  $2500.  Regarding  these  fires,  the 
annual  report  of  the  Boston  Board  of  Fire  Underwriters  stated: 

There  was  perhaps  not  one  of  these  thirty  buildings  where 
the  fires  were  thus  promptly  extinguished  by  the  automatic 
sprinklers  in  which  the  insurance  companies  did  not  have  at 
risk  at  least  $50,000,  while  in  a  number  of  instances  the  insurance 
involved  amounted  to  several  hundred  thousand  dollars.  It 
should  be  added  that  in  most  of  these  instances  the  buildings 
were  used  in  part,  at  least,  for  manufacturing  purposes,  and  if  the 


SPRINKLER   SYSTEMS 


897 


fire  had  attained  headway,  it  could  not  easily  have  been  extin- 
guished. 

Sprinkler  Statistics  of  National  Fire  Protection  Asso- 
ciation, etc.  —  The  most  complete  statistics  of  fires  in  sprin- 
klered  risks  are  those  compiled  by  the  National  Fire  Protection 
Association.  All  sprinkler  fires  of  whatever  nature  throughout 
the  United  States  which  are  reported  to  that  Association  by 
members  or  through  other  channels  are  tabulated  and  classified 
by  card-index,  and  annual  summaries  of  such  fires  are  published. 
These  records  have  been  carefully  kept  since  the  formation  of  the 
Association  in  1897. 

The  April,  1911,  Quarterly  Magazine  of  the  National  Fire 
Protection  Association  gives  the  following  summary  for  the  year 
1911  and  for  the  fourteen  years'  record  from  1897  to  1911 : 

EFFECT  OF  SPRINKLERS  IN   FIRES. 


Number  of  fires. 

Per  cent,  of  num- 
ber with  data 
given. 

1911 

1897  to  1911 

1911 

1897  to 
1911 

Practically    at    entirely    extin- 
guished fire  
Held  fire  in  check  

Total  successful  

646 
403 

7,181 
3,514 

59.48 
37.11 

63.79 
31.22 

1049 
37 

10,695 
562 

96.59 
3.41 

95.01 
4.99 

Unsatisfactory  
Total  .  .                 

1086 

11,257 

Statistics  of  Unsatisfactory  Fires.  —  Unless  the  sprinkler 
supervisory  system  is  used,  the  personal  equation  necessarily 
enters  into  all  sprinkler  protection,  as  is  more  fully  pointed  out 
in  following  paragraphs  and  also  in  Chapter  XXXVI  on  Inspection 
and  Maintenance;  hence  4.99  per  cent,  of  unsatisfactory  fires  in 
a  very  complete  record  of  fourteen  years  is  certainly  commendable 
if  not  remarkable.  These  statistics  are  still  more  favorable  to  the 
purely  mechanical  functions  of  the  automatic  sprinkler,  differen- 
tiated from  the  human  agency  which  often  determines  their 
efficiency  or  failure,  when  the  causes  of  the  unsatisfactory  fires 
are  investigated.  Thus,  the  53  unsatisfactory  fires  reported  in 


898         FIRE    PREVENTION   AND    FIRE   PROTECTION 

1907  resulted  in  a  partial  or  total  failure  of  the  sprinkler  service 
to  perform  its  proper  functions  for  the  following  causes: 

Water  shut  off  for  unknown  reason,  neglect  or  carelessness  8 

Water  shut  off  due  to  freezing 1 

Water  shut  off  before  fire  was  out 4 

Water  shut  off  due  to  repairs 1 

Water  shut  off,  system  out  of  service 2 

Water  shut  off  in  generator  room 1 

Water  shut  off  due  to  flood 1 

*Generally  defective  or  obsolete  equipment,  including  unap- 

proved  or  defective  sprinklers 7 

*Hazard  of  occupancy  and  construction  beyond  control  of 

sprinklers  as  installed 1 

Exposure 5 

Fire  occurring  in  unsprinkled  section  of  building 2 

Obstructions  to  distribution 3 

Water  supplies  or  system  crippled  by  explosion 4 

*Fire  gained  headway  under  light  water  pressure 1 

*Supply  system  crippled  by  freezing 2 

*Concealed  spaces 1 

*High-test  heads  failed . ' 1 

*Inoperative  or  defective  dry  valve 1 

*Insufficient  water  supply  through  street  connection 1 

Waterworks  supply  defective  or  temporarily  out  of  service .  .  1 

*Slow-acting  dry  system 1 

Fire  outside  of  building  or  on  roof 1 

*Sprinklers  clogged 1 

^Defective  sprinkler  alarm 1 

Gravity  tank  temporarily  out  of  service 1 

Total 53 

Thus  in  18  cases,  or  34  per  cent,  of  the  total,  failure  occurred 
through  the  remedial  shutting  off  of  water  supplies;  while  in  only 
18  other  cases  (those  marked  with  an  asterisk  in  the  above  table) 
could  the  sprinkler  mechanism  itself  be  held  accountable.  Expo- 
sure fires,  fires  spreading  from  unsprinklered  portions  of  a  building, 
obstructions  to  distribution  (usually  caused  by  tenants  in  stacking 
contents),  explosions,  water  works  or  gravity  tanks  out  of  service, 
fires  on  roofs,  are  all  causes  which  should  not  properly  be  con- 
sidered legitimate  failures  in  the  sprinkler  service  itself.  Could 
elements  of  danger  of  a  similar  nature  be  entirely  eliminated,  the 
fire  problem  would  be  solved. 

Two  other  particularly  interesting  facts  are  presented  by  the 
tabulations  of  the  National  Fire  Protection  Association,  namely, 
that  in  1897-1911,  while  710  fires  were  discovered  and  reported 
by  the  sprinkler  alarm,  only  57  fires,  or  8  per  cent.,  failed  promptly 


SPRINKLER   SYSTEMS 


899 


to  report  by  sprinkler  alarm,  also  that  30  per  cent,  of  all  sprinkler 
fires  from  1897  to  1911  inclusive  called  into  action  but  one  sprinkler 
head. 
Wet-pipe  Versus  Dry-pipe  Statistics.*  — 


Efficiency  of  wet  or  dry  system. 

Number  of  fires. 

Per  cent,  of  fires. 

tn 

P 

IH 

£g 

4 

£  ® 

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Js.J-JT? 

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Wet  system.  .  .  . 

974 

71 

58 

5.2 

681 

236 

57 

70 

24 

6 

Dry  system.  .  .  . 

392 

29 

60 

11.7 

236 

112 

44 

60 

29 

11 

Total  

1366 

59 

7.0 

917 

348 

101 

67 

26 

7 

It  will  be  noted  that  about  30  per  cent,  of  all  fires  occurred  in 
risks  protected  by  the  dry-pipe  system.  The  average  pressure 
was  about  the  same  with  either  system.  The  average  number 
of  sprinklers  opened  was  considerably  more  than  twice  as  many 
with  the  dry  system  as  with  the  wet  system.  The  percentage  of 
unsatisfactory  fires  was  nearly  twice  as  great  with  the  dry  system 
as  with  the  wet. 

A  brief  analysis  of  these  44  dry  system  failures  is  as  follows: 

Defective  dry  valve  or  apparatus 4 

Too  many  sprinklers  on  a  dry  valve 4 

Slow  action  of  dry  system  combined  with  obstructions 2 

New  dry  valve  being  installed 1 

Freezing  of  improperly  drained  system 1 

Making  a  total  of  12  fires  where  the  unsatisfactory  action  of 
the  sprinklers  is  largely  if  not  entirely  due  to  the  fact  that  there 
was  a  dry  system.  This,  it  will  be  noted,  is  a  little  over  a  quarter 
of  the  whole  number  of  unsatisfactory  fires  on  a  dry  system. 

The  other  32  fires  may  be  classified  as  follows: 

Fire  started  in  unsprinklered  portions 6 

Water  shut  off 5 

Sawdust  or  other  dust  explosions .  . 4 

Generally  defective  equipment 3 

Exposure  fires 3 

Dry  kiln  fires 3 

Dip  tank  fires 2 

Miscellaneous 6 

*  See  April,  1908,  "Quarterly"  of  National  Fire  Protection  Association. 


900          FIRE    PREVENTION    AND    FIRE    PROTECTION 

The  12  unsatisfactory  fires  where  the  dry  system  was  ac- 
countable for  the  failure  of  the  sprinklers  illustrate  several  im- 
portant demands: 

First,  to  use  only  approved  dry-pipe  apparatus,  thus  elimi- 
nating as  much  as  possible  the  chances  of  failure  of  dry-pipe  valve 
itself. 

Second,  to  have  a  small  number  of  sprinklers  on  a  single  dry 
system.  (The  rules  require  not  exceeding  500  heads  on  a  single 
dry-valve.) 

Third,  system  to  be  arranged  so  as  to  drain  properly,  and 
great  care  to  be  taken  that  all  water  be  drained  from  system  dur- 
ing cold  weather. 

Fourth,  whenever  a  dry  valve  is  sent  away  for  repairs  or  a 
new  dry  valve  is  being  installed,  care  to  be  exercised  to  keep  water 
on  system  as  much  as 'possible  or  to  have  system  intact  so  that 
water  can  be  turned  on  in  case  of  need.  The  rules  require  that  a 
dummy  flange  be  kept  on  hand  so  that  it  may  be  inserted  in  the 
riser  and  thus  keep  the  system  intact. 

With  dry  systems  it  is  more  than  ever  necessary  to  have  out- 
side control  for  the  sprinkler  system  so  that  water  may  be  turned 
on  sprinklers  without  going  into  the  building. 

Unsatisfactory  Sprinkler  Fires.  —  In  further  reference  to 
the  aforementioned  unsatisfactory  sprinkler  fires,  the  Commit- 
tee of  the  National  Fire  Protection  Association  on  "  Special 
Hazards  and  Fire  Record "  reported  as  follows:* 

The  Association  year  1906-7  is  especially  noteworthy  in 
the  large  number  of  heavy  losses  due  to  failure  of  sprinklers  to 
hold  fire  in  check.  Beginning  with  the  Lynn  fire  in  December, 
1906,  there  was  a  regular  epidemic  of  serious  fires,  including 
Marietta,  Ga.,  Dover,  N.  H.,  Springfield,  Mass.,  Buffalo,  N.  Y., 
Philadelphia,  Pa.,  and  Troy,  N.  Y.,  all  occurring  inside  of  two 
months  and  approximating  a  property  loss  of  twro  million  dollars 
in  seven  fires.  Nothing  like  this  has  ever  before  happened  in  the 
history  of  sprinklered  risks,  and  the  reasons  therefor  deserve 
careful  study. 

Three  of  these  fires,  or  over  half  of  the  total  loss,  were  due 
to  water  being  shut  off  the  sprinklers,  and  in  each  case  the  sprin- 
kler system  would  otherwise  undoubtedly  have  controlled  the  fire 
with  small  loss.  The  Dover  case  was  a  peculiar  one  in  that  the 
system  was  shut  off  for  a  very  brief  period  to  replace  a  broken 
sprinkler. 

The  Springfield  case  was  a  mistake  of  a  nightman  in  shut- 
ting off  the  water  before  fire  was  entirely  extinguished.  The 
Philadelphia  case  appears  to  have  been  pure  carelessness  in  leav- 
ing valve  closed  after  some  repairs.  The  other  serious  fires  men- 
tioned were  due  to  boiler  explosion,  frozen  system  or  obstruction 
from  waste  paper  stock,  generally  defective  system,  and  stock 

*  See  Eleventh  Annual  Proceedings. 


SPRINKLER    SYSTEMS  901 

piled  around  sprinklers.  With  one  exception  the  risks  would  have 
been  classed  as  good  in  that  the  equipments  were  generally  satis- 
factory and  should  have  controlled  the  fire  with  small  loss  under 
normal  conditions. 

The  table  shows  that  during  the  last  year  there  were  18  fires 
where  water  was  shut  oft*  for  one  reason  or  another,  this  being 
34%,  or  over  one-third,  of  all  the  unsatisfactory  fires.  A  larger 
percentage  than  heretofore,  and  emphasizing  still  further  the  im- 
portance of  keeping  gate  valves  open  at  all  times.  This  is  prob- 
ably the  most  important  problem  that  confronts  those  interested 
in  automatic  sprinkler  protection.  A  satisfactory  and  properly 
maintained  sprinkler  supervisory  service  should  be  of  much  value, 
and  these  systems  are  being  carefully  investigated. 

Defective  or  partial  equipments,  faulty  building  construc- 
tion and  exposure,  as  usual,  play  an  important  part,  but  perhaps 
teach  no  new  lessons,  simply  emphasizing  anew  these  features. 
There  were  four  cases  of  sprinkler  systems  crippled  by  explosion, 
this  being  more  than  has  ever  before  occurred  in  any  one  year 
and  aggregating  nearly  8%  of  the  whole  number  of  unsatisfactory 
fires.  One  was  a  boiler  explosion  causing  a  loss  of  about  $500,000, 
two  were  dust  explosions  and  one  a  natural-gas  explosion. 

Of  the  unusual  occurrences  may  be  noted  one  fire  in  saw- 
dust on  roof,  one  case  of  sprinklers  clogged  by  cinders  or  gravel, 
one  case  where  a  dry-valve  alarm  failed  and  a  large  gravity  tank 
was  drained  before  fire  was  discovered,  and  one  instance  where 
there  was  temporarily  no  automatic  supply  to  sprinklers  due  to  a 
new  gravity  tank  being  installed;  also  there  were  two  serious 
losses  directly  due  to  flood,  this  being  a  distinctly  new  hazard  in 
connection  with  sprinklered  risks. 

Altogether  the  "  sprinklered  mortality,"  if  such  it  may  be 
called,  is  particularly  noteworthy,  there,  however,  being  much 
consolation  in  the  fact  that  these  troubles  can  be  largely  overcome 
through  a  proper  understanding  of  the  problems  involved  and 
the  cooperation  of  the  assured;  furthermore,  another  year's 
record  goes  to  still  further  prove  that  the  automatic  sprinkler  of 
approved  type  is  absolutely  reliable,  sure  in  action  and  certain 
to  control  fires  under  normal  conditions  with  the  system  in 
service. 

Examples  of  Unsatisfactory  Fires.  —  The  epidemic  of  seri- 
ous sprinkler  fires  referred  to  in  the  opening  paragraph  of  the  above 
report  is  remarkable  in  that  three  such  serious  fires  in  sprinklered 
risks  occurred  within  a  single  week:  namely,  the  Cocheco 
Cotton  Mill  at  Dover,  N.  H.,  on  January  26,  1907,  the  plant  of 
the  Phelps  Publishing  Company,  Springfield,  Mass.,  on  January 
28,  and  a  machine  shop  of  the  Baldwin  Locomotive  Works  at 
Philadelphia,  Pa.,  on  January  29.  The  aggregate  property  loss 
by  these  three  fires  was  over  $1,000,000,  and  there  is  little  wonder 
that  their  occurrence  within  so  short  a  space  of  time  should  have 


902         FIRE    PREVENTION    AND    FIRE    PROTECTION 

caused  misgivings  as  to  the  reliability  of  sprinklers,  on  the  part 
of  owners  and  insurance  interests. 

Inasmuch  as  each  one  of  these  fires  forcibly  illustrates  the  great- 
est weakness  inherent  in  sprinkler  protection,  namely,  the  absolute 
necessity  for  either  intelligent  human  control  —  including  constant 
inspection  and  prompt  and  systematic  repair  —  or  sprinkler  su- 
pervisory service,  it  will  be  worth  while  very  briefly  to  outline 
the  fires  in  question. 

The  Cocheco  Mill  Fire.  —  This  building  was  five  stories  in 
height  and  of  extensive  area,  built  of  brick  walls  and  heavy  plank 
and  timber  floors  and  roof.  The  sprinkler  equipment  was  not 
up  to  present  standards  in  all  particulars,  but  it  was  considered 
satisfactory,  and  the  water  supplies  and  fire-fighting  facilities  were 
ample.  Ten  minutes  after  the  mill-hands  had  started  work,  a 
sprinkler  head  opened  on  the  fourth  floor  and  the  room  overseer 
ran  down  the  stairway  and  ordered  the  watchman  to  close  the 
valve  on  the  riser.  Returning  to  his  room,  he  began  to  care  for 
the  water  discharged  by  the  sprinkler,  when  he  noticed  smoke 
coming  from  one  of  the  main  belt  boxes.  Seeing  fire  below,  he 
immediately  sent  a  man  to  order  the  watchman  to  re-open  the 
sprinkler  valve.  "The  word  sent  to  the  watchman  to  re-open  the 
valve,  though  delayed,  finally  reached  him,  but,  disconcerted  by 
the  rush  of  the  help  from  the  mill,  he  became  confused  and  did  not 
open  the  valve.  The  agent  reached  the  mill  ten  or  twelve  minutes 
after  the  fire  started  and  had  the  valve  opened  at  once,  but  on 
opening  it  the  pressure  at  the  base  of  the  riser  fell  to  thirty  pounds, 
showing  that  so  many  sprinklers  had  opened  that  the  excellent 
public  water  supply  could  not  maintain  a  serviceable  pressure."* 

It  would  immediately  occur  to  one  that  the  fire  must  have 
started  before  the  opening  of  the  sprinkler  head  on  the  fourth 
floor,  and  have  been  the  cause  of  such  opening,  but,  "carefully 
weighing  all  the  evidence,  the  probabilities  are  that  the  fourth 
floor  sprinkler  opened  by  chance  failure  of  the  link,  the  water  wet 
the  belts,  one  of  them  slipped  and  ran  sidewise,  rubbing  against 
the  casing  and  starting  a  fire."* 

Of  course  the  primary  cause  of  the  whole  disaster  was  the  giving 
way  of  the  single  head,  but  it  is  remarkable  that  the  escape  of 
water  should  occur  in  just  such  a  manner  as  to  cause  fire,  and  it 
would  be  idle  to  condemn  sprinklers  ad  libitum  for  such  an  excep- 

*  Report  of  the  Boston  Manufacturers'  Mutual  Fire  Insurance  Com- 
pany. 


SPRINKLER    SYSTEMS  903 

tional  occurrence.  The  failure  of  individual  heads  is  infrequent, 
considering  the  great  number  used,  and  the  resulting  damage  is 
almost  always  trifling,  as  can  be  verified  by  the  reports  of  the 
Boston  Manufacturers'  Mutual  Fire  Insurance  Company. 

The  real  lessons  taught  by  this  fire  are  the  dangers  attendant 
upon  the  use  of  belt  openings  from  floor  to  floor,  and  especially 
the  use  of  unsprinklered  belt  boxes,  fly-wheel  housings,  and  similar 
enclosures;  and  the  danger  in  a  running  mill  when  sprinklers  are 
shut  oft7.  Had  all  machinery  been  stopped  until  the  sprinkler 
head  was  replaced,  or  had  a  thoroughly  reliable  man  been  stationed 
at  the  valve  until  it  was  re-opened,  the  result  would  doubtless  have 
been  far  different. 

Phelps  Publishing  Company  Fire.  —  The  Phelps  publish- 
ing plant  at  Springfield,  Mass.,  consisted  of  a  four-  and  five-story 
brick  structure,  generally  of  "mill  construction,"  and  divided  into 
three  sections  —  the  "old  building,"  the  "new  building"  and  the 
"new  addition"  —  by  fire  doors,  which  were  mostly  open  at 
time  of  fire.  The  roof  was  a  slate-covered  mansard.  The  auto- 
matic sprinklers  were  supplied  by  high-service  city  water,  and  by 
pump  drawing  from  low-service  mains. 

The  fire,  which  started  at  3:15  a.m.,  was  discovered  in  the  base- 
ment by  the  colored  watchman,  who,  with  the  night  fireman, 
fought  the  blaze  with  chemical  extinguishers.  Believing  that  the 
fire  had  been  extinguished  by  the  means  employed  and  by  the 
sprinkler  heads  which  had  opened,  the  sprinkler  system  was  shut 
off  to  prevent  water  damage.  About  a  half-hour  later  fire  was 
again  discovered  by  the  watchman  in  making  his  rounds,  and  it 
seems  probable  that  this  second  blaze  was  caused  by  the  first  fire 
working  inside  the  sheathed  walls.  Owing  to  the  automatic 
sprinklers, being  shut  off,  the  subsequent  failure  of  the  city  water 
supply,  and  the  bursting  of  the  hose  employed  by  the  city  fire  de- 
partment, the  plant  was  almost  totally  destroyed. 

Baldwin  Locomotive  Works  Fire.  —  This  fire  caused  a  loss 
estimated  at  $100,000  to  $150,000  because  of  incomplete  equip- 
ment and  water  shut  off.  The  fire  was  discovered  at  5:30  P.M. 
in  a  drafting  room  partitioned  off  at  one  end  of  the  third  story. 

In  putting  in  the  ceiling  of  this  room  the  sprinklers  had 
been  removed  and  not  replaced.  The  fire  was  first  discovered 
in  this  room,  but  it  had  gathered  such  headway  that  it  burst 
through  the  partition  and  spread  down  the  room,  and  also  through 
the  open  elevator  way  to  the  story  above.  Unfortunately  the 


904         FIRE    PREVENTION    AND    FIRE    PROTECTION 

water  was  shut  off  from  the  sprinkler  equipment  in  the  whole 
group,  the  valve  controlling  the  same  being  closed.* 

Limitations  of  Sprinkler  Protection.  —  From  the  foregoing 
brief  descriptions  of  fires  and  from  the  data  accumulated  by  the 
National  Fire  Protection  Association,  it  will  be  seen  that  sprinklers 
cannot  be  considered  a  substitute  for  fire-resisting  construction, 
as  any  failure  of  the  sprinkler  equipment  itself,  failure  of  water 
supplies,  or  any  error  in  the  human  factors  of  continued  vigilance, 
inspection  or  judgment  means  ruin  for  the  structure. 

They  are  applicable  only  in  part  to  places  not  heated  in 
freezing  weather;  they  should  receive  constant  inspection  by  all 
parties  interested;  they  will  never  reduce  the  incendiary  hazard 
caused  by  scamps  who  know  enough  to  shut  off  the  water;  they 
will  not  defend  against  the  conflagration  hazard ;  neither  can  they 
be  relied  upon  to  control  any  fires  except  those  starting  in  rooms 
which  they  protect.  They  are  not  applicable  in  full  measure  to 
buildings  containing  large  open  spaces  of  great  height,  nor  to 
those  containing  deep  piles  of  combustible  material.  Like  all 
other  mechanical  devices  they  are  subject  to  depreciation,  which 
is  particularly  active  in  industries  generating  corrosive  vapors 
or  producing  viscous  products  which  adhere  to  the  sprinklers. f 

Nevertheless  sprinklers  have  been  called  "the  greatest  economic 
invention  of  the  present  generation."  Heretofore  used  only  in 
non-fire-resisting  buildings,  their  use  is  now  gradually  extending 
to  a  wide  range  of  fire-resisting  structures,  not  so  much  on  account 
of  the  protection  directly  afforded  the  buildings  as  in  recognition 
of  their  great  value  in  controlling  incipient  fires  in  the  stock  and 
contents.  A  broad  view  of  fire  protection  should  consider  safe- 
guards almost  as  important  as  fire-resisting  construction  per  se, 
as  any  means  which  tend  to  extinguish  or  limit  fire  are  of  incalcu- 
lable value. 

Use  of  Sprinklers  in  Hotels.  —  A  very  timely  paper  on  "The 
Season  Hotel,"  namely,  the  summer  or  winter  hotel  occupied  for 
a  brief  season  only,  was  presented  by  Mr.  H.  L.  Hiscock  before  the 
eleventh  annual  meeting  of  the  National  Fire  Protection  Associa- 
tion. After  describing  the  construction  of  several  thoroughly  fire- 
resisting  hotels,  such  as  the  "New  Blenheim"  and  "Chalfonte" 
at  Atlantic  City,  and  the  "Antlers  Hotel"  at  Colorado  Springs, 
etc.,  the  author  speaks  as  follows  concerning  the  construction  of 
non-fire-resisting  hotels : 

*  Insurance  Engineering,  March,  1907.         "    f  C.  J.  H.  Woodbury. 


SPRINKLER   SYSTEMS  905 

The  most  essential  feature  in  this  class  of  risks  is  the  pro- 
vision against  the  spread  of  fires  and  the  apparatus  for  quick 
service  in  extinguishing  them.  While  in  the  old  days  it  was  hard 
to  convince  the  proprietor  of  the  necessity  of  the  protection  appli- 
ances, he  now  seeks  the  suggestions  of  insurance  people  on  this 
subject.  In  the  past,  the  presence  of  fire  appliances  was  con- 
sidered an  eyesore  and  thought  to  lack  beauty,  but  now,  as  the 
public  is  more  and  more  concerned  with  the  fire  hazard,  especially 
in  hotels  where  they  intend  to  stop,  such  objections  have  largely 
disappeared.  Plenty  of  hand  hose  and  a  good  water  supply, 
with  fire  extinguishers,  are  now  an  attractive  advertisement. 
Automatic  sprinklers  are  now  being  introduced  in  the  more 
hazardous  parts  of  the  risk,  which  is  desirable  protection. 

As  a  good  example,  the  "Poland  Spring  House,"  Maine, 
is  claimed  by  many  to  have  the  best  equipment  for  protection 
against  fire  of  any  in  the  country.  This  is  an  isolated  risk. 
The  sprinkler  system  covers  the  entire  upper  two  floors  of  the 
hotel,  also  blind  attic,  tops  of  towers,  top  of  elevator,  toilet  rooms, 
porters'  room,  linen  closets,  stage  of  music  room,  help's  kitchen 
and  laundry,  and  entire  tower  at  westerly  corner  of  hotel  above 
first  floor.  This  is  a  dry  system  and  kept  in  commission  in  win- 
ter; about  sixteen  hundred  sprinklers  in  all  and  controlled  by 
three  dry  valves  located  in  the  basement  of  kitchen  (floor  over- 
head fireproof).  Supplies  for  this  system  consist  of  10,000  gallon 
tank  on  trestle  in  yard,  this  being  in  commission  the  entire  year; 
second  supply,  1000-gallon  Underwriters'  steam  pump  in  boiler 
house,  in  readiness  during  the  summer  only;  third  supply,  pumps 
at  lake,  giving  twenty  to  forty  pounds'  pressure  at  hotel  level. 
There  are  also  three  standpipes,  with  hose,  on  each  floor,  so  ar- 
ranged that  all  parts  of  building  may  be  reached  by  streams. 
Standpipes  are  supplied  by  fire  pumps.  There  is  also  a  good 
supply  of  pails  and  chemical  extinguishers.  The  outside  pro- 
tection consists  of  eight  hydrants  near  hotel  on  six-  and  eight-inch 
loop,  supplied  by  Worthington  1,000  gallon  Underwriters'  steam 
pump,  located  in  boiler  house,  draughting  from  cistern  of  28,000 
gallons'  capacity,  which  can  be  filled  by  pumps  at  lake.  There  is 
a  good  equipment  of  2J-inch  rubber  lined  hose  and  play  pipes 
located  at  several  convenient  points.  There  is  also  a  night  watch- 
man, with  clock,  during  the  season  and  in  the  winter,  covering 
only  the  outside  of  building. 

Use  of  Sprinklers  in  Car  Barns.  —  Another  very  interesting 
and  important  development  of  sprinkler  protection  concerns  the 
equipment  of  car  barns,  used  for  the  storage  of  electric  street 
railway  cars,  than  which  few,  if  any,  risks  prove  so  generally  de- 
structible, and  which,  at  the  same  time,  so  seriously  inconvenience 
the  general  public.  Previous  to  the  introduction  of  aisle  sprinklers, 
the  ordinary  ceiling-sprinkler  installation  had  proved  totally  in- 
efficient in  this  character  of  risk  for  the  reason  that  the  units  of 


906 


FIRE   PREVENTION   AND   FIRE   PROTECTION 


cars  to  be  guarded  required  interior  protection,  and  manifestly 
this  could  not  be  supplied  by  ceiling  sprinklers  over  the  roofs  of 
the  cars.  Realizing  that  no  conclusive  data  existed  on  the  sub- 
ject, notwithstanding  several  tests  undertaken  in  1904,  the  Com- 
mittee on  Installation  of  Automatic  Sprinklers  of  the  National  Fire 
Protection  Association,  in  conjunction  with  the  Car  Barn  Com- 
mittee, instituted  a  series  of  fire-burning  tests  in  a  modern  car 
barn  at  Cleveland,  April  24, 1905,  the  building  being  fully  equipped 
with  ceiling  and  aisle  sprinklers,  and  the  tests  being  made  under 
conditions  as  extreme  as  possible.  As  a  result  of  these  tests  it  has 
been  shown  conclusively  that  a  fire  can  be  confined  to  a  single 
car,  and  that,  if  the  sprinklers  are  properly  installed,  the  loss  on  a 
car  body  should  not  exceed  $500. 

The  experiments  indicate  that  satisfactory  results  can  be 
obtained  by  placing  sprinkler  lines  on  either  side  of  cars,  with 
sprinkler  deflectors  opposite  transom  lights,  heads  to  be  not  over 
8  feet  apart  on  line,  and  sprinkler  lines  to  be  not  over  16  inches 
from  car,  preferably  not  over  6  inches.* 

Table  of  Allowances  for  Sprinkler  Protection.  —  The  fol- 
lowing table  of  allowances  for  sprinkler  protection  is  employed 
by  the  Boston  Board  of  Fire  Underwriters: 

AUTOMATIC  SPRINKLER  SYSTEM    (TWO  SUPPLIES). 


I 

Allow- 
ance, 
wet-pipe 
system. 

Allow- 
ance, 
dry-pipe 
system. 

With  automatic  fire  alarm,  watch,  watch  super-  ) 
vision  and  sprinkler  notification  ) 
With  watch,    automatic   fire   alarm,   sprinkler  ( 
notification  and  auxiliary  alarm  f 
With  watch,   watch  supervision  and  sprinkler  | 
notification                                            j 

Per  cent. 

50 
47! 
47! 

Per  cent. 
40 

37J 
37! 

With  automatic  fire  alarm  and  sprinkler  notifi-  ) 
cation  ( 

45 

35 

With  watch,  sprinkler  notification  and  auxiliary  ) 
alarm                                                                        j 

45 

35 

With  watch  and  watch  supervision               

42J 

32^ 

With  watch  and  auxiliary  alarm  

42k 

32! 

With  watch  and  automatic  fire  alarm  
With  watch  and  sprinkler  notification  

42| 
42J 

32! 

32! 

With  automatic  fire  alarm 

40 

30 

With  watch                                            

40 

30 

*  For  full  report  of  committee,  also  photographs  of  fires,  etc.,  see  Ninth 
Annual  Proceedings  of  National  Fire  Protection  Association. 


SPRINKLER   SYSTEMS  907 

An  approved  electric  notification  system  in  connection  with  an 
approved  automatic  sprinkler  system  (two  supplies)  consists  of 
(a)  the  electric  notification  to  a  Central  Station  of  the  opening  or 
closing  of  any  .gate-valve;  (6)  the  similar  notification  of  the  flow 
of  water  in  the  main  riser  when  equivalent  to  a  flow  of  a  single 
sprinkler  head;  (c)  the  similar  notification  of  a  change  in  the 
height  of  water  in  a  gravity  tank  or  the  pressure  of  water  in  a 
pressure  tank;  (d)  the  similar  notification  of  a  change  of  tempera- 
ture, between  certain  fixed  limits,  of  water  in  gravity  or  pressure 
tank.* 

AUTOMATIC  SPRINKLERS  (ONE  SUPPLY). 

Where  only  one  source  of  water  is  permanently  connected  and 
where  such  connection  from  the  street  main  is  satisfactory  to  the 
Inspection  Department  and  gives  a  static  pressure  of  not  less  than 
twenty-five  pounds  on  the  highest  head  in  the  building  and  where 
a  steamer  connection  is  installed,  the  allowances  for  the  above 
combinations  will  be  uniformly  less  by  10  per  cent,  of  the  premium. 

An  approved  electric  notification  system  in  connection  with  an 
approved  automatic  sprinkler  system  (one  supply)  consists  of  (a) 
the  electric  notification  to  a  Central  Station  of  the  opening  or  clos- 
ing of  any  gate- valve;  (b)  the  similar  notification  of  flow  of  water 
in  the  riser  when  equivalent  to  flow  of  a  single  sprinkler  head. 

*  See  "Automatic  Sprinkler  Alarms  and  Supervisory  Systems,"  page  919. 


CHAPTER  XXXI. 

AUTOMATIC  FIRE  ALARMS,  AND  SPRINKLER  ALARM 
AND    SUPERVISORY   SYSTEMS. 

Discovery  of  Fire.  —  The  usual  means  by  which  fires  are  dis- 
covered are 

1.  Occupant  of  premises, 

2.  Outsider,  or  chance  passer-by, 

3.  Watchman, 

4.  Automatic  fire  alarm,  and 

5.  Sprinkler  alarm,  or  supervisory  system. 

Statistics  naturally  show  that  more  fires  are  discovered  by 
occupants  or  employees  than  by  any  other  means,  but  this  source 
of  discovery,  as  also  that  by  outsiders  who  may  chance  to  be 
passing,  cannot  be  relied  upon  when  the  premises  are  deserted, 
when  the  occupants  are  asleep,  or  during  late  night  hours  when 
passers-by  are  infrequent.  For  the  prompt  discovery  of  fire, 
therefore,  recourse  must  be  had  to  some  special  form  of  alarm 
service. 

Ordinary  watchman  service  is  very  unsatisfactory  unless  con- 
ducted under  the  strictest  supervision,  and  even  then  watc'.men 
are  often  very  unreliable  and  apt  to  do  precisely  the  wrong  thing 
in  case  of  emergency,  as  is  pointed  out  in  more  detail  in  Chapter 
XXXIII. 

The  desire  to  provide  some  means  of  discovering  fire,  which 
should  be  automatic  and  hence  superior  to  the  human  element 
involved  in  watchman  service,  led  to  the  introduction  of  automatic 
sprinklers,  which,  acting  as  both  fire  alarms  and  fire  extinguishers, 
constitute  the  most  efficient  means  of  fire  protection  so  far  de- 
vised. Automatic  fire  alarm  systems,  used  to  detect  the  presence 
of  fire  or  dangerously  high  temperatures,  rank  second  in  the  scale 
of  automatic  fire  protection  measures,  for,  manifestly,  next  to  the 
actual  extinguishment  of  fire,  the  most  important  consideration 
is  knowledge  of  the  fact  that  fire  or  danger  exists. 

The  "Sprinkler  Fire  Tables"  of  the  National  Fire  Protection 
Association,  which  are  revised  annually  to  give  statistics  concern- 

908 


AUTOMATIC    FIRE    ALARMS,  ETC. 


909 


ing  all  fires  reported  in  sprinkler  risks,  contain  the  following  table 
relative  to  the 

EFFICIENCY  OF  ALARM  SERVICE,   1897-1911,  INCLUSIVE. 


KS 

Satisfactory. 

Failure. 

Total. 

No.  of 
fires. 

Per 
cent. 

No.  of 
fires. 

Per 
cent. 

Watchman  alone  

851 
710 
142 

90 
93 
79 

90 
57 
37 

10 

7 
21 

941 

767 
179 

Sprinkler  alarm  alone  
Thermostats  alone  

Watch- 
man. 

Sprink- 
ler 
alarm. 

Ther- 
mostat. 

Super- 
visory. 

I 

Satisfactory. 

Failure. 

Satisfactory. 

Failure. 

Satisfactory. 

Failure. 

Satisfactory. 

Failure. 

Watchman     and     sprinkler 
alarm.  
Watchman  and  thermostats 
Sprinkler  alarm  and   ther- 
mostats 

549 

7 

316* 
3* 

740 

125 

"9 
216 
46 

1 

77 
18 
3 

.  .  t 

865 
10 

293 
64 
14 

2 
16 

271 
57 
14 

22 

7 

14 
2 

Watchman,  sprinkler  alarm 
and  thermostats    .  . 

28 

36* 

Sprinkler  alarm  and  super- 
visory system.  .    . 

Thermostats,    sprinkler 
alarm     and     supervisory 
system  

2 

2 

Watchman,  sprinkler  alarm 
and  supervisory  system.  .  . 

9 

7* 

16 

16 

*  These  include  fires  where  sprinkler  alarm  or  thermostats  notified  the  watch- 
man. 

NOTE.  —  These  tables  do  not  include  fires  where  alarm  service  does  or  does  not 
operate  promptly  if  fire  is  at  once  discovered  by  employee,  the  alarm  service 
having  no  bearing  on  such  fires  one  way  or  the  other. 

It  will  be  noted  that,  in  the  above  comparison  of  single  forms 
of  alarm  service,  —  as  watchman,  sprinkler  alarm,  or  thermostats, 


910          FIRE    PREVENTION    AND    FIRE    PROTECTION 

when  used  without  combination  with  other  forms,  —  the  per  cent,  of 
failures  for  the  fifteen  years  covered  by  the  above  table  is  greatest 
for  automatic  alarms,  i.e.,  thermostats,  while  for  the  year  1911  alone 
(see  table  on  page  878)  the  latter  form  of  alarm  showed  100  per 
cent,  efficiency.  This  is  principally  explained  by  the  fact  that  prior 
to  about  1905  very  few  automatic  alarm  systems  were  connected 
with  central  stations,  save  in  five  or  six  cities..  Most  installations 
were  without  either  connection  to  or  supervision  by  an  operating 
company,  hence  both  maintenance  and  service  were  often  deficient. 
Only  systems  operating  through  a  central  station  are  now  approved. 

Automatic  Fire  Alarm  Systems  depend  upon  thermostats, 
or  heat-detectors  —  usually  placed  upon  ceilings  —  for  the  indi- 
cation of  fire  or  dangerously  high  temperatures.  The  thermostat 
causes  an  electric  circuit  to  be  either  completed  or  broken,  as  will 
be  explained  later,  thus  causing  an  alarm  to  be  sounded. 

Installations  of  automatic  fire  alarm  systems  are  now  largely 
confined  to  city  buildings,  where  the  system  is  connected  with  a 
central  station,  —  operated  by  an  alarm  company,  —  which,  in 
turn,  transmits  the  alarm  to  the  fire  department. 

The  rules  and  requirements  of  the  National  Board  of  Fire  Under- 
writers require  such  central  stations  to  have  two  independent 
means  of  transmitting  alarms  to  the  fire  department,  and  to  have, 
at  all  times,  at  least  two  competent  persons  in  charge.  The  system 
must  be  arranged  to  receive,  record  and  transmit  to  the  public 
fire  department  and  insurance  patrol  the  box  number  of  the  build- 
ing in  which  a  thermostat  has  operated;  and,  unless  the  floor 
number  is  also  transmitted  with  the  alarm  to  the  fire  department, 
a  local  annunciator,  placed  on  or  in  the  building,  as  may  be  re- 
quired by  the  inspection  department  having  jurisdiction,  must 
automatically  register  the  floor  number  of  the  disturbance.  Such 
annunciator  boxes  are  seldom  used,  however,  —  except  where 
desired  for  the  convenience  of  the  occupants,  as  in  large  depart- 
ment stores,  etc.,  —  for  the  reason  that  the  alarm  companies 
usually  transmit  to  the  fire  department  both  .the  number  of  the 
building  and  also  a  designation  of  the  floor  or  fire  section  where 
the  disturbance  is  located.  The  great  time-saving  value  of  this 
knowledge  to  the  fire  department  is  apparent. 

All  systems  must  be  so  arranged  as  to  give,  automatically,  dis- 
tinctive trouble  signals  when  any  part  of  the  wiring  of  the  system 
is  grounded  or  broken,  or  when  the  proper  transmission  of  a  fire 
signal  is  in  any  way  impaired. 


AUTOMATIC    FIRE   ALARMS,  ETC.  911 

Not  more  than  fifteen  building  equipments  may  be  connected 
on  any  single  circuit,  unless  the  circuit  is  mainly  under  ground. 

The  installation  of  thermostats,  in  outlying  or  country  risks, 
has  not  generally  proved  satisfactory,  owing  principally  to  poor 
inspection  and  maintenance,  rather  than  to  defects  in  mechanism. 

Installation  of  Thermostats  and  Manual  Boxes.  —  The 
National  Board  rules  require  that  thermostats  must  be  placed  as 
follows : 

Throughout  premises,  including  insides  of  all  closets,  in 
basements,  lofts,  elevator  wells  and  under  stairs.  Special  in- 
structions must  be  obtained  relative  to  placing  them  under  large 
shelves,  decks,  benches,  tables,  overhead  storage  racks  and  plat- 
forms and  inside  small  enclosures,  such  as  drying  and  heating 
boxes,  caul  boxes,  tenter-  and  dry-room  enclosures,  chutes  and 
cupboards.  No  portion  of  the  premises  shall  be  excepted  without 
written  consent. 

The  spacing  of  thermostats  upon  ceilings,  etc.,  is  generally  the 
same  as  given  for  sprinklers  on  page  870,  but  installations  should 
always  be  referred  to  the  inspection  department  of  the  Under- 
writers having  jurisdiction. 

The  ordinary  method  of  installing  thermostats  is  to  place  them 
on  the  ceilings,  with  the  wiring  run  in  plain  sight.  If  desired, 
however,  all  of  the  wiring  may  be  concealed  within  insulated  piping 
or  electrical  conduits,  which  are  then  covered  and  hidden  by  the 
plastering.  Nothing  need  be  visible  save  the  thermostats  them- 
selves, and  these  may  easily  be  made  to  conform  to  the  general 
tone  of  the  ceiling  or  wall  finish. 

Manual  Alarm  Boxes,  connected  with  the  thermostat  system, 
are  required  to  be  located  at  all  main  exits  and  at  each  floor  exit. 
These  are  installed  in  order  that  the  occupants  of  the  building 
need  not  wait  for  any  possible  fire  to  reach  a  temperature  sufficient 
to  operate  a  thermostat,  but,  upon  discovery,  an  alarm  may  at 
once  be  sounded  to  the  central  station.  Such  manuals  are  also 
valuable  in  case  fire  is  seen  in  nearby  property. 

For  further  information  regarding  manual  boxes,  see  page  955. 

Types  of  Automatic  Fire  Alarm  Systems.  —  Automatic 
fire  alarm  systems  are  of  two  general  types,  depending  upon  the 
form  of  electric  circuit  employed. 

Closed  Circuit.  —  In  this  type  electricity  is  utilized  to  prevent 
the  operation  of  the  recording  device  by  flowing  continuously 
through  the  system.  The  action  of  the  thermostat  under  sufficient 
heat  causes  the  circuit  to  be  broken,  thereby  interrupting  the  con- 


912          FIRE    PREVENTION   AND   FIRE   PROTECTION 

trol  of  the  electric  current  over  the  signalling  mechanism  and 
indicating  apparatus,  and  thus  allowing  the  alarm  to  be  given. 

Open  Circuit.  —  In  this  type  the  action  of  the  thermostat  closes 
or  completes  the  circuit,  thus  causing  the  electric  energy  to  operate 
the  alarm. 

Thermostats.  —  As  before  stated,  thermostats  are  located  on 
ceilings,  etc.,  under  practically  the  same  rules  of  spacing  as  apply 
to  automatic  sprinkler  heads.  The  operating  temperatures  are 
determined  for  each  premises  by  the  fire  alarm  company  in  con- 
junction with  the  Underwriters  having  jurisdiction,  but,  in 
general,  it  may  be  stated  that  they  are  usually  set  to  operate  at 
temperatures  from  30  to  50  degrees  above  the  normal  maximum 
temperature  to  be  expected.  Thus,  for  ordinary  locations  where 
the  temperature  never  exceeds  125  degrees  F.,  thermostats  are 
used  with  operating  temperatures  of  130  degrees  to  160  degrees. 
Thermostats  up  to  250  degree  action  are  sometimes  used  in  boiler- 
and  dry-rooms. 

Thermostats  are  of  two  general  types :  those  operating  by  solder 
release,  and  those  operating  by  expansion. 

Solder  Release  Thermostats  depend  upon  the  use  of  fusible  solder, 
precisely  as  used  in  automatic  sprinkler  heads.  Thermostats  of 
this  type  are  usually  set  at  160  degrees  F.,  as  the  ordinary  solder 
employed  releases  at  that  temperature. 

Expansion  Thermostats  depend  for  their  operation  upon  the  ex- 
pansion of  either  metals  or  liquids  under  heat.  Among  the  liquids 
used  are  ether  and  mercury,  which,  expanding  within  glass  or 
metal  tubes,  cause  the  circuit  to  be  completed.  In  those  thermo- 
stats depending  upon  the  expansion  of  metal  springs,  the  well- 
known  unequal  expansion  of  two  dissimilar  metals  is  utilized  in 
order  to  magnify  the  amount  of  motion. 

Requisites.  —  The  points  to  be  considered  in  examining  a 
thermostat  are: 

Sensitiveness,  that  is,  the  quickness  with  which  the  required 
degree  of  heat  will  operate  the  device. 

Durability,  or  the  degree  to  which  the  device  will  resist 
injury  from  repeated  variations  in  temperature,  which  will  always 
occur,  even  when  not  subjected  to  a  sufficient  heat  to  actually 
operate  the  device;  also  ability  to  resist  the  corrosive  effects  of 
the  atmosphere  and  such  other  vapors  to  which  it  may  be  ex- 
posed. 

Accuracy,  of  the  nearness  of  the  temperature  at  which  the 
device  will  successfully  operate,  to  the  temperature  at  which  it  is 
supposed  to  operate. 


AUTOMATIC    FIRE   ALARMS,  ETC.  913 

The  thermostat  must  also  be  so  constructed  as  to  prevent 
the  corrosion  of  the  contact  points,  or  failure  to  make  a  contact 
due  to  the  accumulation  of  dust  and  other  foreign  substances; 
and,  at  the  same  time,  be  sufficiently  exposed  to  feel  quickly  any 
abnormal  rise  in  temperature.  It  must  also  be  well  insulated  so 
as  to  do  away  with  the  liability  of  leakage  (and  consequent  run- 
ning down  of  batteries)  across  any  of  the  exposed  portions  which 
are  used  as  a  part  of  the  electric  circuit.* 

The  necessity  for  sensitiveness  and  positive  action  on  the  part 
of  thermostats  is  also  emphasized  by  the  fact  that  they  are  fre- 
quently installed  in  risks  which  are  also  equipped  with  sprinklers, 
or  risks  which  may  at  any  time  become  so  equipped.  It  is  there- 
fore desirable  that  there  be  as  great  a  margin  of  sensitiveness  be- 
tween the  thermostat  and  sprinkler  as  possible,  for  two  reasons: 
first,  if  the  thermostat  operates  quickly,  the  alarm  may  be  given 
and  the  fire  extinguished  by  hand  before  water  damage  ensues 
from  the  opening  of  sprinkler  heads;  second,  if  the  sprinklers 
should  operate  first,  the  water  discharge  therefrom  is  very  likely 
so  to  lower  the  temperature  as  to  prevent  the  operation  of  the 
thermostat.  "With  the  thermostat,  therefore,  the  aim  is  extreme 
sensitiveness  or  quickness  of  action,  and  the  only  limit  in  this  case 
is  that  it  be  not  set  so  low  as  to  operate  under  ordinary  conditions 
and  give  false  alarms." 

There  is  no  type  of  thermostat  to-day  on  the  market  which  fulfills 
all  of  the  requirements  of  the  Underwriters'  Laboratories,  Inc., 
but  there  are  four  makes  which  are  generally  approved  for  use: 
viz.,  the  "Watkins"  expansion  spring,  the  " United  States"  solder 
release,  the  "Woodman"  solder  release,  and  the  "National"  ex- 
pansion. The  "Watkins"  and  the  "United  States"  thermostats 
have  had,  a  wide  and  successful  field  use  for  many  years. 

Details  of  Thermostats.  —  A  "  Watkins"  thermostat  is  illus- 
trated in  Fig.  375  to  two-thirds  actual  size.  The  perforated  sheet- 
metal  case  is  for  protection  only,  having  no  connection  with  the,., 
operation  of  the  device.  The  bottom  and  side  perforations  of 
the  case,  and  an  opening  all  around  the  top  between  the  case  and 
the  ceiling  plate,  are  provided  to  permit  a  free  circulation  of  air 
over  the  interior  spring,  in  order  to  avoid  the  possibility  of  having 
a  cushion  of  cold  air  within  the  thermostat.  This  is  to  render 
the  device  as  sensitive  as  possible. 

*  See  "Thermo-electric  Fire  Alarms,"  by  C.  M.  Goddard  in  "First  Annual 
Transactions  of  National  Fire  Protection  Association," 


914 


FIRE    PREVENTION    AND    FIRE    PROTECTION 


A  plan  of  the  mechanism,  drawn  to  two-thirds  size,  is  shown  in 
Fig.  376.     The  binding  posts,  for  the  connection  of  the  electric 


FIG.    375.  —  "Watkins"   Expansion  Spring  Thermostat. 

wiring,  are  shown  at  aa,  to  one  of  which  is  connected  the  perforated 
metal  spring  s,  which  is  supported  on  an  upright,  or  post,  b.  The 
free  end  of  the  spring  terminates  in  a  flattened  end,  or  shoe,  c.  To 
the  other  binding  post  is  connected  another  upright,  or  support, 
d,  penetrated  by  a  platinum  point  p,  the  adjustment  of  which 


FIG.   376.  —  Mechanism  of  "Watkins"  Thermostat. 

will  render  the  thermostat  operative  at  almost  any  degree  of  sen- 
sitiveness. The  expansion  of  the  spring,  under  the  predetermined 
degree  of  heat,  causes  the  spring  to  move  until  the  end  c  comes  in 
contact  with  the  point  p,  thus  completing  the  electrical  circuit. 
The  adjustment  may  be  made  so  sensitive  that  an  increase  of  a 
few  degrees  of  temperature  is  sufficient  to  make  the  contact,  while 
the  heat  of  the  breath  will  readily  operate  a  thermostat  of  this 
type  if  set  within  delicate  range. 


AUTOMATIC    FIRE    ALARMS,  ETC.  915 

The  electrical  contact  thus  made  in  the  thermostat  operates  an 
electro-magnet  within  a  signal  box  located  on  the  premises.  This 
transmits  the  alarm  to  the  central  station,  where,  in  turn,  it  is 
transmitted  to  the  city  fire  department.  The  particular  box 
number  which  is  transmitted  indicates  the  building  and  the  floor 
therein,  where  the  fire  or  dangerously  high  temperature  exists. 
This  method  of  automatically  registering  both  the  building  and 
the  floor  forms  a  most  valuable  feature. 

The  " United  States"  thermostat  is  illustrated  two-thirds  size 
in  Fig.  377.  This  is  a  closed  circuit,  solder-release  thermostat. 


FIG.    377.  —  "United    States"    Solder-release    Thermostat. 

They  are  always  run  in  pairs,  and  are  so  arranged  that  the  opera- 
tion of  one  thermostat  will  cause  a  " trouble"  signal,  while  the 
operation  of  two  thermostats  —  viz.,  the  breaking  of  two  cir- 
cuits —  will  cause  the  transmitter  within  the  signal  box  to  give 
a  distinctive  fire  alarm. 

The  thermostat  consists  of  a  brass  ring,  to  which  are  soldered, 
by  means  of  fusible  solder,  two  short  lengths  of  metal  tubing  into 
which  the  stripped  ends  of  the  insulated  wires  are  connected.  The 
melting  of  the  fusible  solder  breaks  the  circuit,  with  result  as 
before  explained. 

The  "Aero"  Automatic  Fire  Alarm*  is  an  English  system, 
wherein,  as  the  name  implies,  the  expansion  of  air  is  utilized  for 
the  purpose  of  transmitting  fire  alarms. 

The  apparatus  consists  of  continuous  copper  tubes,  ?Vin.  ex- 
ternal diameter,  which  are  distributed  internally  around  the  prem- 
ises to  be  protected  —  usually  on  or  near  the  ceiling,  similarly 
to  bell  wires.  Each  floor  or  separate  portion  of  premises -has  its 
own  tube,  the  two  ends  of  which  are  connected  to  a  pressure  re- 
corder, which  is  practically  a  double  aneroid  barometer  diaphragm. 
Under  the  action  of  heat  or  fire,  the  expansion  of  the  copper  tubing 

*  For  illustrated  description  of  apparatus  and  tests,  see  also  "Red  Book" 
No.  153  of  the  British  Fire  Prevention  Committee. 


916          FIRE    PREVENTION   AND    FIRE    PROTECTION 

is  negligible,  but  the  air  expands  approximately  2io  part  of  its 
volume  for  each  degree  of  rise,  Centigrade.  As  pressure  varies 
directly  as  volume,  the  pressure  in  the  tube  varies  directly  as  the 
temperature.  A  slow  rise  of  temperature  causes  pressure  in  the 
tube  which  escapes  at  a  relief  valve;  but  a  sudden  rise  of  tem- 
perature causes  more  pressure  in  the  tube  than  can  escape  at  the 
valve,  hence  it  acts  upon  the  aneroid  chamber,  expanding  it  until 
it  comes  against  an  insulated  contact  screw  which  is  set  a  certain 
distance  in  front  of  it.  This  closes  an  electrical  circuit,  which 
drops  an  indicator,  rings  a  fire  gong,  and  actuates  a  transmitter 
which  turns  in  the  alarm  to  the  fire  department. 

Every  ten  feet  of  the  tubing  may  be  looked  upon  as  a  thermo- 
stat, which  will  turn  in  the  alarm  individually,  but,  in  addition, 
for  smouldering  fires,  the  pressure  developed  in  each  ten-foot 
length  is  added  to  the  adjacent  pressures,  and  the  effect  on  the 
whole  is  cumulative.  In  other  words,  partial  effects  are  added 
together  and  aggregate  a  fire  effect. 

The  transmission  employed  in  this  system  is,  of  course,  a  trans- 
mission of  pressure,  and  not  of  air.  Waves  of  compression  and 
rarefaction  travel  along  the  tube  at  about  1100  feet  per  second, 
but  the  air  particles  do  not  move  an  eighth  of  an  inch.  The  action 
of  air  in  a  speaking  tube  is  exactly  similar. 

While  the  Underwriters'  Laboratories,  Inc.,  have  given  their 
approval  to  this  device,  nevertheless  the  field  experience  of  the 
system  has  been  of  so  short  a  duration  that  its  value  as  an  efficient 
fire  alarm  has  not  been  fully  demonstrated. 

Vapor  Thermostats. —  "  #ed  Book  "  No.  94  of  the  British 
Fire  Prevention  Committee  gives  a  very  interesting  detailed  report 
and  tests  of  the  "Autopyrophone,"  which  is  an  automatic  fire- 
detector  in  which  pressure  of  vapor  from  a  volatile  spirit,  resulting 
from  expansion  under  increase  in  temperature,  is  applied  to  a 
column  of  mercury  in  a  glass  tube,  causing  the  displacement  of 
the  mercury,  with  the  consequent  opening  of  a  closed  electric 
circuit,  this  being  arranged  so  as  to  close  a  secondary  open  circuit 
by  which  signals  are  given  for  transmission  to  any  desired  place. 
The  various  calls  given  by  the  apparatus  include  a  danger  call,  a 
trouble  call,  and  a  fire  call,  the  latter  being  transmitted  automati- 
cally or  manually  to  the  fire  department. 

Journal-bearing  Thermostats.  —  Automatic  alarms  or 
thermostats  are  used  to  some  extent  in  connection  with  journal 
bearings,  especially  in  grain  elevators,  wherein  the  accumulations 


AUTOMATIC    FIRE    ALARMS,  ETC. 


917 


of  grain  dust  and  the  small  pockets  at  corners  of  bins  have  largely 
prevented  the  successful  use  of  automatic  sprinklers. 

Solder-release  journal-bearing  thermostats  may  be  installed  at 
all  journal  bearings,  set  to  give  alarm  at  practically  160  degrees  F. 
Such  a  thermostat  is  shown  in 
Fig.  378.  A  is  a  brass  shell,  the 
base  of  which  is  screwed  into  the 
journal  box.  BB  are  two  nickel 
steel  binding  posts,  connected 
by  wires  to  the  alarm  bells  which 
are  located  at  suitable  places. 
C  is  a  circuit  closer  or  plunger, 
resting  on  a  cone-shaped  spring 
D,  which  rests  against  shoulders 
EE  when  depressed.  The  lower 
end  of  circuit  closer  F  is  held 
down  or  in  position  by  fusible 
solder  G,  which,  melting  at  a 
temperature  of  160  degrees,  re- 
leases the  plunger,  which  is  then 
pressed  upward  by  the  spring 
until  in  contact  with  the  binding 
posts  BB,  thus  completing  the 
circuit  and  sounding  the  alarm. 
Finding  switches  and  annunci- 
ators may  also  be  installed  by  which  trouble  on  any  particular 
machine  or  bearing  may  be  instantly  located. 

For  rules  governing  installation,  etc.,  see  National  Board  of  Fire 
Underwriters'  pamphlet  "  Signaling  Systems." 

Automatic  Fire  Alarms  in  Baltimore  Conflagration.  — 
The  great  importance  of  knowledge  regarding  the  breaking  out 
of  fire  or  the  presence  of  dangerously  high  temperatures  in  prem- 
ises, and  the  necessity  for  acting  at  once  upon  such  knowledge, 
were  most  forcibly  illustrated  in  the  circumstances  surrounding 
the  start  of  the  Baltimore  conflagration. 

It  will  be  remembered  that  that  fire  started  in  the  Hurst  store 
building,  a  six-story  non-fire-resisting  structure  which  was  equipped 
with  an  automatic  fire  alarm  system.  The  first  intimation  of 
existing  trouble  was  the  receipt,  over  the  automatic  fire  alarm 
system,  at  the  central  station,  of  a  "trouble"  or  danger  signal, 
''but  as  the  establishment  (i.e.,  the  store  building)  was  closed, 


FIG.  378.  —  Journal    Bearing 
Thermostat. 


918        FIRE    PREVENTION    AND    FIRE    PROTECTION 


without  watchman  or  other  person  on  the  premises,  the  first  signal, 
which  was  really  the  commencement  of  a  fire  call,  was  disregarded," 
possibly  because  of  the  trouble  involved  in  an  investigation,  or 
possibly  because  of  the  difficulty  of  access,  without  damage,  to 
a  building  closed  after  business  hours.  But,  whatever  the  reason 
for  this  neglect,  a  definite  fire  alarm  was  received  over  the  auto- 
matic system  twenty-five  minutes  later,  in  answer  to  which  the 
fire  department  was  summoned.  The  neglected  interval,  how- 
ever, allowed  the  accumulation  in  the  upper  portions  of  the  build- 
ing of  smoke  and  gases,  the  ignition  of  which  resulted  in  the 
explosion  which  went  so  far  to  wreck  the  structure  and  to  commu- 
nicate the  fire  to  neighboring  property.  Had  the  human  agency 
of  control  been  as  reliable  as  the  automatic  agency  of  discovery, 
the  result  might  have  been  far  different. 

Fortunately,  such  failures  to  follow  up  any  indications  of  trouble 
coming  in  over  automatic  fire  alarm  services  are  very  rare,  while 
the  contingency  of  having  to  investigate  premises  closed  after 
fixed  business  hours  has  been  provided  for  in  the  adoption  (1907) 
by  the  National  Fire  Protection  Association  of  the  following  rule: 

Arrangements  must,  if  possible,  be  made  by  the  operating 
company,  by  which  they  shall  have  access  to  premises  under 
supervision  at  all  hours  of  the  day  and  night.  Where  such 
arrangements  cannot  be  made  and  it  might  become  necessary 
to  force  an  entrance  to  the  building  a  proper  guard  shall  be 
placed  over  the  building  so  long  as  required. 

Allowances  for  Automatic  Fire  Alarm.  —  Allowances  made 
by  the  Boston  Board  of  Fire  Underwriters  and  by  the  New  York 
Fire  Insurance  Exchange  for  approved  automatic  fire  alarm  sys- 
tems are  as  follows: 


Boston 
Board. 

N.Y.  Fire 
Insurance 
Exchange. 

Automatic  fire  alarm  

Per  cent. 
10 

Per  cent. 
10 

Automatic    fire    alarm,    watchman    and 
watch  clock 

12J 

12| 

Automatic     fire     alarm,     and     auxiliary 
alarm,  no  watchman.  .                             .    . 

12J 

Automatic  fire  alarm,  watchman  and  watch 
clock  with  central  station  supervision.  .  . 
Automatic    fire    alarm,    watchman    and 
watch  clock,  and  auxiliary  alarm  

15 

17| 

AUTOMATIC    FIRE    ALARMS,  ETC.  919 

AUTOMATIC  SPRINKLER  ALARMS  AND  SUPERVISORY  SYSTEMS. 

Usual  Causes  of  Sprinkler  Failures.  —  In  the  previous  chap- 
ter, attention  was  called  to  the  fact  that  many  sprinklered  risks 
are  damaged  or  destroyed  through  remedial  causes,  such  as  water 
supplies  shut  off,  low  water  levels,  freezing,  inadequate  tank-  or 
steam-pressure,  etc.;  while  in  Chapter  XXXVI,  the  inspection 
and  maintenance  of  sprinkler  installations  are  considered  at  length, 
principally  from  the  standpoint  of  eradicating  such  causes  of 
failure.  Contingencies  as  enumerated  above,  however,  may  be 
automatically  guarded  against  by  the  installation  of  sprinkler 
alarm  and  supervisory  service,  which,  while  not  obviating  defects 
of  building  construction,  or  insufficient  or  inoperative  heads, 
etc.,  still  constitutes  the  greatest  improvement  made  in  auto- 
matic sprinkler  equipment  since  the  introduction  of  modern 
methods. 

Central  Station  Sprinkler  Supervisory  Service  consists  of 
equipping  the  sprinkler  system  with  electrical  devices  which  auto- 
matically signal  the  central  station  of  the  operating  company 
whenever  abnormal  conditions  arise  in  the  system  which  would 
interfere  with  its  proper  working.  In  approved  systems  of  this 
nature,  this  is  accomplished  by  means  of  two  separate  circuits,  — 
one  for  water  flow,  which  constitutes  a  fire  alarm,  —  and  the  other 
for  supervisory  service,  i.e.,  the  detection  of  interference  or  abnor- 
mal conditions  in  the  features  supervised.  It  is  essential  for  the 
best  maintenance  of  the  service  that  a  distinct  separation  be  made 
in  these  two  functions  of  the  system. 

Operation.  —  Each  feature  of  the  service  is  provided  with  a 
special  type  of  signaling  device,  relay  and  transmission  box,  and 
each  is  fitted  with  tamper  alarms.  The  devices  operate  primarily 
on  local  battery  circuits,  which  extend  from  the  device  to  the 
transmission  boxes,  and  secondarily  on  outside  circuit,  there  being 
normally  no  contact  between  the  two  circuits. 

When  the  local  circuit  is  opened  by  action  of  the  device  from 
tampering  or  any  other  cause,  a  notched  or  character  wheel  is  set 
in  operation,  which,  on  the  supervisory  circuit,  makes  two  revolu- 
tions designating  "trouble,"  and  one  revolution  when  same  ia 
returned  to  normal  position.  On  fire  alarm  circuits  a  similar 
operation  takes  place,  except  that  the  character  wheel  revolves 
five  times. 

The  movement  of  these  character  wheels  mechanically  opens 


920          FIRE    PREVENTION    AND    FIRE    PROTECTION 

the  outside  circuit,  which  extends  from  the  transmission  boxes  to 
the  instrument  board,  and  thus  transmits  the  signals  to  the  central 
station.  Each  revolution  of  the  various  character  wheels  registers 
a  distinctly  different  signal  on  the  tape  register  at  the  instrument 
board,  and  for  fire  signals  the  number  of  alarm  is  preceded  by  the 

letter  "F"  in  Morse  code  ( ),  signifying  fire.  The  fire  signal 

is  also  simultaneously  announced  by  the  tapping  of  a  small  gong 
located  on  the  central  board,  and  at  the  scene  of  fire  by  the  ringing 
of  local  electric  bells. 

All  fire  alarms  are  at  once  transmitted  to  the  public  fire  depart- 
ment. " Trouble"  signals  are  at  once  investigated  by  a  " runner" 
who  is  dispatched  to  the  building.  The  assured  is  also  notified 
at  once  by  telephone. 

The  Water-flow  or  Fire  Alarm  is  effected  by  means  of  a  con- 
nection with  the  alarm  valve  in  such  manner  as  to  cause  a  water- 
flow  signal,  which  is  virtually  a  fire  alarm,  when  one  or  more 
sprinkler  heads  operate.  On  wet  systems,  a  retarding  device 
prevents  the  sending  in  of  false  alarms  for  water  hammer  or  other 
temporary  variations  in  pressure,  by  withholding  the  water-flow 
signal  for  a  period  of  fifteen  to  twenty  seconds.  Thus,  in  case  of 
temporary  disturbance,  a  "trouble"  signal  of  one  round  is  trans- 
mitted. If  a  continuous  water-flow  exists,  the  " trouble"  signal 
is  followed  by  five  rounds  of  the  box,  this  constituting  a  \vater- 
flow  alarm. 

Supervisory  Service.  Gate-Valves.  —  Attachments  are  made 
to  all  gate-valves  which  are  under  the  control  of  the  assured, 
in  such  manner  that  two  and  one-half  turns  of  any  valve  stem 
cause  a  signal  to  be  transmitted  to  the  central  station  in  the  super- 
visory circuit.  A  different  signal  is  given  as  soon  as  the  valve  is 
restored  to  normal  position. 

Pressure.  —  Dry-pipe  systems  are  arranged  to  transmit  signals 
at  about  10  pounds  excess  above  a  fixed  pressure  of  35  pounds. 

Attachments  to  pressure  tanks  give  high  and  low  pressure  signals 
at  6  pounds  below  and  15  pounds  above  a  normal  pressure  of  80 
pounds. 

Steam  pressure  attachment  is  adjusted  to  give  a  low  pressure 
signal  at  45  pounds. 

All  of  the  above  devices  automatically  record  the  restoration 
of  normal  pressures. 

Water  Levels.  —  Gravity  tanks,  reservoirs  or  cisterns  used  as 
sources  of  water  supply  are  equipped  with  " ball-float"  attach- 


AUTOMATIC    FIRE    ALARMS,  ETC.  921 

ments  which  give  low  water  signal  for  a  drop  of  6  inches  below 
required  level. 

Temperature.  —  Gravity  tanks  and  reservoirs,  etc.,  where  sub- 
ject to  freezing,  are  also  equipped  with  thermometer,  located  about 
two  feet  below  the  water  level,  and  adjusted  to  give  signal  when 
the  temperature  falls  below  37  degrees  F.,  or  when  it  rises  above 
165  degrees  F. 

Automatic  Fire  Pumps  are  also  equipped  with  complete  super- 
visory apparatus  for  attachment  to  all  steam-,  discharge-  and 
suction-valves. 

Manual  Boxes  are  furnished  and  installed  as  a  part  of  sprin- 
kler supervisory  systems.  These  are  connected  with  the  central 
station  and  are  relayed  to  the  city  fire  department  in  the  usual 
manner. 

Inspection  and  Supervision.  —  The  operating  companies 
usually  inspect  all  risks  every  two  weeks.  Such  inspections  in- 
clude wrorking  tests  of  the  various  devices  installed. 

Daily  reports  are  issued  by  the  company,  showing  receipt  of  all 
signals,  their  time  and  nature,  and  when  restored  to  normal  con- 
dition. 

Allowances  for  "  Sprinkler  Notification  "  Service,  as  practised 
by  the  Boston  Board  of  Fire  Under  writers,  are  given  in  combina- 
tion with  other  means  of  protection  on  page  906. 

In  the  practice  of  the  New  York  Fire  Insurance  Exchange,  the 
installation  of  sprinkler  supervisory  service  increases  the  allowance 
for  automatic  sprinklers  by  20  per  cent.,  in  addition  to  which 
watchman  service  is  allowed  5  per  cent.  No  allowances  are  then 
made  for  either  automatic  fire  alarm  system  or  auxiliary  boxes. 


CHAPTER  XXXII. 

SIMPLE    PROTECTIVE    DEVICES.      FIRE    PAILS    AND 
EXTINGUISHERS;   PAINTS   AND   SOLUTIONS. 

Simple  Protective  Devices.  —  In  the  absence  of  automatic 
means  of  detecting  or  extinguishing  fire,  and  even  in  the  absence 
of  an  adequate  water  supply  under  pressure,  complete  reliance  for 
the  extinguishment  of  fire  should  not  be  placed  upon  the  public 
fire  department.  In  such  cases,  the  prompt  and  intelligent  use 
of  very  simple  protective  devices  will  generally  mean  the  difference 
between  an  incipient  fire  of  trifling  magnitude,  or  a  fire  which,  five 
minutes  later,  may  require  an  entire  fire  department.  There  are 
comparatively  few  instances  in  the  occupancy  of  buildings  where 
it  is  impracticable  to  install  simple  auxiliary  devices,  and  still 
fewer  instances  where  such  installations  would  not  prove  of  value 
in  case  of  fire.  Thus  in  the  case  of  the  fire  in  the  State  Capitol  at 
Albany,  N.  Y.,  an  occupant  of  the  building  at  the  time  of  the 
fire  stated  that  "the  fire  at  this  time  could  easily  have  been  put 
out  with  a  pail  or  two  of  water.  We  searched  in  vain  for  anything 
to  serve  the  purpose." 

The  efficiency  of  such  auxiliary  "first  aids,"  however,  will  be 
found  to  be  dependent  upon  several  contingencies,  such  as  organi- 
zation of  employees  or  tenants  to  insure  prompt  and  effective 
action,  handy  location,  and  the  reliability  or  working  order  of  the 
auxiliary  aids  provided. 

Fire  Pails.  —  The  simplest,  cheapest  and  best  fire  extinguisher 
yet  devised  is  a  pail  of  water.  Hence  fire  pail  equipments  have 
long  been  a  recognized  protective  device  of  great  value,  and  as 
such  are  generally  given  stated  allowances  in  insurance  ratings, 
provided  they  are  installed  and  maintained  under  stated  rules 
and  regulations.  The  following  specifications  for  fire  pail  equip- 
ments are  enforced  by  the  New  York  Fire  Insurance  Exchange : 

Installation.  —  A.  The  installation  of  fire  pails  in  various 
buildings  is  determined  by  the  rating  schedule  applied  to  the 
buildings.  As  a  rule,  rating  schedules  provide  that  fire  pails  are 
required  in  all  buildings  used  for  business  purposes,  such  as  fac- 

922 


SIMPLE   PROTECTIVE    DEVICES,  ETC.  923 

tories,  wholesale  or  retail  stores,  warehouses,  offices  and  office 
buildings,  etc.,  but  not  in  churches  or  premises  occupied  for 
dwelling  purposes. 

B.  Pails  are  required  to  be  placed  throughout  the  entire 
premises  occupied  for  business  purposes.     This  includes  base- 
ments,  sub-basements,    attics,    mezzanines   or   galleries,    exten- 
sions —  in  brief,  every  floor  and  every  part  of  a  floor  used  for 
business  purposes. 

C.  In  buildings  of  non-fire-resisting  construction,  the  entire 
building  and  all  tenants  in  the  building  are  required  to  provide 
fire  pails,  as  a  condition  to  the  allowance  being  granted  to  any 
tenant  in  the  building. 

D.  In   buildings   of   fire-resisting   construction,    each   floor 
is  considered  a  separate  unit,  and  accordingly  all  tenants  on  any 
one  floor  are  required  to  provide  pails  as  a  condition  to  the 
allowance  being  granted  to  any  tenant  on  that  particular  floor. 
When  a  floor  is  divided  into  sections  by  fire-resisting  partitions, 
each  section  is  considered  a  separate  unit  and  is  treated  accord- 
ingly. 

Number  of  Pails*  —  A.  For  a  floor  space  of  1000  square 
feet  or  less,  two  pails  are  required,  and  for  each  additional  500 
square  feet  or  fraction  thereof,  an  additional  pail  is  required. 

Examples.  —  A  floor  space  of  1000  sq.  ft.  or  less  requires  two 
pails. 

A  floor  space  of  1000  to  1500  sq.  ft.  requires  three  pails. 

A  floor  space  of  1500  to  2000  sq.  ft.  requires  four  pails. 

A  floor  space  of  2500  to  3000  sq.  ft.  requires  six  pails. 

B.  The  number  of  pails  required  on  any  one  floor  depends 
on  the  area  of  that  particular  floor,  and  is  not  governed  by  the 
number  required  for  floors  above  or  below. 

Pails.  — 

A.  To  be  galvanized  iron. 

B.  Capacity  10  or  12  quarts. 

C.  To  be  painted  red. 

D.  To  be  lettered  "FIRE,"  or  "FOR  FIRE  ONLY."     Letters 
to  be  black,  not  less  than  2|  inches  high. 

E.  Round  bottom  recommended  for  establishments  where 
employees  are  likely  to  use  pails  for  ordinary  purposes. 

F.  Covers  not  required,  but  recommended. 

G.  Wooden  pails  will  not  be  accepted  under  any  circum- 
stances. 

Setting.  — 

A.  To  be  fixed,  permanent,  and  reserved  for  fire  pails. 
Brackets,  shelves  or  benches  are  the  approved  setting,  but  they 
must  be  intended  for,  and  limited  in  their  use  to,  fire  pails.  Fire 

*  The  rules  of  the  National  Board  of  Fire  Underwriters  call  for  number  and 
arrangement  as  required  by  Underwriters  having  jurisdiction,  but  not  less  than 
one  dozen  pails  to  every  5000  square  feet  of  floor  area.  Not  over  one-half  the 
required  number  of  pails  per  floor  may  be  replaced  by  chemical  extinguishers 
in  the  proportion  of  one  approved  portable  extinguisher  to  six  pails. 


924          FIRE    PREVENTION    AND    FIRE    PROTECTION 

pails  placed  on  floors,  stock  shelves,  window  sills,  radiators,  work 
tables  or  benches,  safes,  desks,  boxes,  or  in  tiers,  will  not  be 
approved  for  the  reduction  in  rate. 

B.  To  be  not  lower  than  two  feet  above  the  floor,  measured 
from  floor  to  bottom  of  pail. 

C.  To  be  not  higher  than  five  feet  above  the  floor,  measured 
from  floor  to  top  of  pail. 

D.  When  round  bottomed  pails  are  set  in  shelves  or  benches, 
the  holes  cut  out  for  the  pails  should  be  only  large  enough  to 
receive  the  oval  bottom ;  that  is,  the  flange  of  the  bottom  should 
rest  on  the  support,  and  not  be  set  into  the  opening. 

Distribution.  — 

A.  To  provide  pails  near  at  hand  in  every  part  of  the  prem- 
ises. 

B.  To  provide  extra  pails  near  dangerous  features. 

C.  In  groups  of  2,  3,  4,  5  or  6,  but  not  larger  than  6. 
Examples.  —  An  equipment  of  12  or  less,  on  a  floor,  to  be 

divided  into  groups  of  2  or  3. 

24  or  less,  on  a  floor,  to  be  divided  into  groups  of  2,  3  or  4. 
More  than  24  on  a  floor,  to  be  divided  into  groups  of  not  more 
than  6. 

D.  Groups  to  be  placed  diagonally  opposite,  i.e.,   "criss 
crossed,"  or  " staggered." 

Location.  — • 

A.  In  clear  space,  providing  free  and  unimpeded  access. 

B.  In  close  proximity  to  exits,  such  as  stairways,  elevators, 
fire  escapes. 

C.  In  a  familiar  place,  within  constant  sight  of  the  occupants. 

D.  In  close  proximity  to  places  where  fire  is  likely  to  start. 

E.  Not  to  be  blocked  by  stock  or  machinery,  or  covered  with 
rubbish  or  other  materials. 

Filling.  —  Water  pails  to  be  refilled  once  a  week  regularly 
with  clean  water. 

Sand  Pails  *  —  Where  oils,  paints  or  inflammable  liquids 
are  kept,  used  or  stored,  one-half  of  the  total  number  of  pails 
required  to  be  kept  filled  with  clean  dry  sand,  and  a  scoop  pro- 
vided for  use  in  throwing  the  sand.  Sand  pails  should  not  be 
filled  so  full  as  to  make  them  inconveniently  heavy.  Two-thirds 
full  is  sufficient. 

Freezing.^  —  When  fire  pails  are  located  where  there  is  a 
liability  of  the  water  being  frozen  in  cold  weather,  it  is  recom- 
mended that  two  pounds  of  chloride  of  calcium,  or  salt  (the  former 
is  preferable),  be  placed  in  each  pail.  For  casks,  the  quantity 
recommended  is  50  pounds  for  each  cask.  It  is  necessary  that  the 
chloride  of  calcium  or  the  salt  be  dissolved  by  thorough  stirring. 

Supervision.  —  The  fire  pail  equipment  to  be  placed  in 
charge  of  the  engineer,  the  janitor,  the  foreman,  the  watchman 
or  some  person  with  authority,  who  will  be  answerable  for  its 
efficiency. 

*  Compare  with  paragraph  "Special  Hazards,"  page  932. 
t  See  also  page  927. 


SIMPLE    PROTECTIVE    DEVICES,  ETC.  925 

Substitutes.  —  Instead  of  ordinary  fire  pails  as  above  de- 
scribed, water  casks  and  pails  or  patent  bucket  tanks  may  be 
substituted  under  the  conditions  given  under  following  headings. 
Or,  chemical  fire  extinguishers  may  replace  not  over  one-half  the 
total  number  of  pails  on  a  floor,  on  the  basis  of  one  approved 
3-gallon  extinguisher  for  six  pails  or  one  cask  and  three  pails. 

hi  Case  of  Fire.  —  When  possible,  fire  pails  should  be  used 
under  the  direction  of  a  competent  person.  Do  not  throw  water 
in  a  wild,  aimless  manner,  but  if  there  is  time,  make  use  of  a 
wetted  broom  to  beat  out  the  fire,  or  blankets  to  smother  it. 

Water  should  not  be  used  on  burning  liquids,  such  as  oils, 
paints,  etc.,  as  it  will  not  extinguish  the  fire  but  will  float  the 
burning  liquids  to  a  distance,  and  thereby  spread  the  fire.  Some 
material,  such  as  sand,  should  be  used,  first,  to  keep  the  burning 
Liquid  from  spreading,  and  then  to  smother  the  fire. 


The  above  regulations,  covering  only  such  a  simple  device  as 
fire  pails,  are,  after  long  and  tried  experience,  found  to  be  in  line 
with  the  old  adage  "be  careful  in  little  things,*  and  large  things 
will  care  for  themselves."  It  has  been  found  advisable  to  require 
that  the  pails  be  painted  red,  with  the  words  "FIRE"  or  "FOR 
FIRE  ONLY"  in  black  letters.  The  red  color  is  useful  because  of 
its  general  association  with  fire;  it  helps  to  make  the  pail  clearly 
visible  when  wanted,  and,  with  the  word  "  FIRE,"  is  a  constant 
reminder  that  the  pail  is  there  for  a  special  purpose,  —  the  putting 
out  of  fire,  —  and  is  not  to  be  taken  away  or  used  for  ordinary 
purposes.  The  placing  at  a  medium  height  is  devised  to  permit 
of  grasping  the  pail  without  spilling  half  its  contents;  if  a  pail  is 
placed  more  than  five  feet  high  it  is  likely  to  be  out  of  the  reach 
of  the  average  person;  and  if  set  lower  than  two  feet  it  is  likely 
to  be  overlooked  or  to  be  knocked  from  its  position.  The  use  of 
an  iron  pail,  in  preference  to  wood  or  other  material,  is  a  matter 
of  service  and  economy,  in  addition  to  the  greater  likelihood  that 
an  iron  pail  will  be  found  serviceable  when  suddenly  wanted  for 
use.  The  requirement  of  a  stated  number  distributed  in  groups 
throughout  the  entire  premises,  is  framed  to  provide  that  pails  % 
shall  be  within  a  hand's  grasp,  and  not  be  distant  anywhere  from 
50  to  200  feet  at  a  time  when  a  tiny  flame  is  rapidly  growing  into 
a  formidable  blaze.  The  insistence  of  a  permanent  setting,  such 
as  hooks  or  shelves,  is  intended  to  make  sure  that  the  pail  will  be 
given  a  fixed  position,  which  will  become  familiar  to  the  occupants 
who,  in  time  of  excitement,  can  rely  on  finding  pails  in  a  definite 
spot.  The  regular  re-filling  is  a  common-sense  precaution  to 


926 


FIRE    PREVENTION   AND    FIRE    PROTECTION 


make  sure  that  the  pails  shall  contain  water.  Such  rules  as  these 
are  part  of  the  usual  discipline  maintained  in  establishments  which 
have  in  view  a  careful  management  of  their  property,  and  a  proper 
observance  of  them  will  tend  greatly  to  reduce  losses  by  fire. 

Sealed  Fire  Pails.  —  The  Waggoner  "  Sanatory  "  fire  bucket, 
made  with  a  lid  sealed  with  wax  to  prevent  contents  from  fouling 
or  evaporating,  is  shown  in  Fig.  379.  These  buckets  are  made  to 
contain  three  gallons  of  water,  but  the  shape  is  such  that  they 
cannot  be  emptied  with  a  single  effort.  The  sealed  lid  may  be 
easily  removed  by  pulling  the  lid  handle.  Calcium  chloride  or 
other  salts  may  be  added  to  render  the  contents  non-freezing. 


FIG.  379.  —  "Sanatory"  Fire  Bucket.     FIG.  380.  —  Safety  Fire  Bucket  Tank. 

Water  Casks.  —  Instead  of  fire  pails,  water  casks  and  pails 
may  be  used  under  the  following  conditions,*  each  cask  to  be  con- 
sidered the  equivalent  of  six  (6)  fire  pails: 

Cask  to  be  a  good  oak  barrel  of  capacity  not  less  than  50  gallons. 
To  be  painted  red,  with  words  "FIRE"  or  "FOR  FIRE  ONLY" 
painted  thereon  in  black  letters  not  less  than  6  inches  high.  To 
have  a  cover  with  a  handle. 

Three  (3)  standard  fire  pails  to  be  placed  on  a  shelf  or  on  hooks 
alongside  the  cask. 

Bucket  Tanks.  —  Ordinary  fire  pails  or  water  casks,  while 
not  usually  objectionable  as  to  appearance  in  manufacturing  or 
storage  buildings  and  the  like,  are  unsightly  in  a  better  class  of 
buildings.  For  such  cases,  a  patent o -1  metal  bucket  tank  is  made 

*  The  Now  York  Fire  Insurance  Exchange. 


SIMPLE    PROTECTIVE    DEVICES,  ETC.  927 

by  the  Safety  Fire  Extinguisher  Co.,  New  York,  wherein  6  metal 
fire  pails  are  immersed  within  a  tank  containing  water,  each  pail 
nesting  within  another  (see  Fig.  380).  This  method  removes  the 
pails  from  view,  keeps  them  free  from  dirt,  and  renders  the  liability 
of  pails  being  empty  or  overturned  less  likely.  If  used  in  exposed 
locations,  a  non-freezing  solution  is  used. 

Bucket  tanks  of  this  character  are  usually  accepted  by  the 
insurance  companies  in  lieu  of  fire  pails  on  the  basis  of  one  tank 
containing  six  pails  to  six  fire  pails,  provided  the  casks  are  fre- 
quently inspected  to  insure  that  covers  lift  readily,  pails  may  be 
easily  withdrawn,  and  casks  are  kept  filled. 

Non-freezing  Solutions  for  Water  Pails,  Casks,  etc.  — 
The  following  facts  and  tables*  concerning  materials  employed  to 
lower  the  freezing  point  of  solutions  may  be  used  as  a  guide,  accord- 
ing to  the  needs  of  the  case  in  hand. 

Common  Salt  has  been  much  used  to  prevent  freezing  of 
water  in  pails,  and  so  forth,  but  it  does  not  lower  the  freezing 
point  sufficiently  to  be  of  very  great  use  in  average  cold  weather. 
If  the  solution  is  too  concentrated  its  disagreeable  propensity 
to  " creep"  and  crystallize  all  over  the  receptacle  makes  it  ex- 
tremely objectionable.  It  will  always  attack  and  rust  metals 
with  more  or  less  rapidity. 

Common  salt,  or  sodium  chloride,  is  the  only  salt  that  has 
been  recommended  for  use  in  chemical  extinguishers,  and  this 
only  by  a  few  manufacturers.  They  advise  the  use  of  one  quart 
of  salt  for  a  three-gallon  tank.  This  will  lower  the  freezing  point 
to  about  15°  F.  above  zero,  but  will  not  withstand  a  continuous 
cold  spell  in  northern  climates. 

The  following  table  gives  the  freezing  points  of  salt  solutions 
of  different  strengths. 

FREEZING  POINT  OF  SALT  SOLUTIONS. 
^Ti^S!Lt0  Free^g  point. 

1  per  cent,  salt 31. 8  degrees  F. 

t5  per  cent,  salt 25. 4  degrees  F. 
10  per  cent,  salt 18. 6  degrees  F. 
15  per  cent,  salt 12. 2  degrees  F. 
20  per  cent,  salt 6.8  degrees  F. 
25  per  cent,  salt 1.0  degrees  F. 
Use  one  pound  of  salt  to  18  gallons  of  water.     Add  four 
aces  of  salt  to  this  solution  for  every  degree  Fahrenheit  below 
30.     One  gallon  of  water  weighs  8.35  pounds. 

*  See  "Freezing  Preventives  for  Water  Pails  and  Chemical  Extinguishers," 
by  J.  Albert  Robinson,  National  Fire  Protection  Association's  "Quarterly," 
January,  1912. 


928         FIRE    PREVENTION    AND    FIRE    PROTECTION 
Another  table  has  been  expressed  as  follows: 

COMMON  SALT  (Sodium  chloride). 
Pounds  per  gallon.  Freezing  point  —  Degrees  Fahrenheit. 

4 24  above  zero 

1    18 

11 15 

li 12 

U 9 

2   6 

21 3 


3    . 3  below  zero 

31  Q  U  (( 

2 O 

The  solution  should  be  mixed  in  a  vat  before  being  placed  in 
barrels,  care  being  exercised  to  see  that  the  salt  is  entirely  dis- 
solved. If  dumped  into  a  barrel  and  covered  with  water,  or  if 
thrown  into  a  barrel  of  water,  the  salt  will  be  only  partially  dis- 
solved and  unsatisfactory  results  obtained.  Barrels  with  wooden 
hoops  should  be  used,  as  salt  will  corrode  steel  hoops  or  steel  tanks. 

Calcium  Chloride.  — 

This  is  a  white,  solid  substance,  like  common  salt,  which 
makes  a  colorless  solution  when  dissolved  in  water.  Unlike  salt 
it  does  not  rust  metal.  It  has,  however,  a  tendency  to  attack 
solder.  Because  of  this,  and  also  the  chemical  reaction  that 
would  be  involved,  it  is  not  suitable  for  use  in  chemical  extin- 
guishers. A  small  amount  of  lime  added  to  the  solution  will 
remove  any  tendency  to  acidity.  It  has  no  odor  and  will  remain 
odorless  even  if  left  standing  for  a  long  time.  It  will  not  evapo- 
rate nor  form  sediment.  Calcium  chloride  is  hygroscopic  and  will 
quite  readily  absorb  moisture  from  the  air.  If  water  freezes, 
this  salt  will  not  "creep"  and  "grow"  (crystallize)  over  the  re- 
ceptacle as  does  common  salt. 

The  following  facts  should  be  taken  into  consideration: 

The  amount  of  calcium  chloride  necessary  to  make  a  satu- 
rated solution  decreases  with  the  temperature  of  the  solution. 
A  solution  which  is  saturated  at  sixty  degrees  will  be  super- 
saturated at  zero,  and  the  excess  crystallizes  out  and  floats  on  the 
surface  of  the  water,  forming  a  film  which  may  collect  dirt  and 
filth.  This  feature  is  not  so  objectionable,  however,  as  the 
crystallization  of  salt,  which  takes  place  under  most  conditions. 

The  Solvay  Process  Company's  75%  fused  or  solid  calcium 
chloride  is  sold  in  thin  sheet-iron  drums  of  610  pounds  capacity, 
at  $20  per  ton.  It  is  also  put  up  in  375  pound  drums  at  about  1| 
cents  per  pound.  It  can  be  bought  from  any  other  dealer  in  heavy 
chemicals.  If  one  is  using  much  calcium  chloride,  it  is  preferable 
to  regulate  the  strength  by  using  a  special  hydrometer  marked 
in  "Degrees  Salometer"  as  well  as  in  "Degrees  Beaume." 

The  f(;ii..;..'ing  table  shows  the  temperature  at  which  water 
will  Ireeze  with  given  quantities  of  calcium  chloride  in  solution: 


SIMPLE   PROTECTIVE    DEVICES,  ETC. 


929 


Pounds,  per 
gallon  of 
water. 

Temperature  of 
freezing. 

Pounds,  per 
gallon  of 
water. 

Temperature  of 
freezing. 

i 

+29  F. 

31 

-  8-11  F. 

1 

27  F. 

4 

-  17-19  F. 

H 

23  F. 

4| 

-27-29  F. 

2 

18  F. 

5 

-39-41  F. 

2i 

+3-4  F. 

5i 

-50-54  F. 

3 

-1-4  F. 

Ring  Handle 


Lead  stopi 


wCap 


Where  calcium  chloride  solution  is  used,  wooden  barrels 
should  first  be  well  coated  inside  with  asphaltum,  or  with  a 
mixture  of  crude  paraffin  and  resin,  to  prevent  shrinking  of  staves 
and  consequent  leakage. 

Chemical  Fire  Extinguishers.  —  In  the  effort  to  provide 
handy  means  of  fire  extinc- 
tion other  than  pails  of 
water,  numerous  devices 
have  been  produced  de- 
pending on  the  use  of 
chemicals.  Most  of  these 
have  proved  unsatisfactory 
in  actual  practice,  but  the 
device  known  as  the  chemi- 
cal fire  extinguisher,  which 
uses  carbonic  acid  gas  and 
water,  has  been  perfected  to 
an  extent  which  makes  it  a 
valuable  fire  appliance  for 
use  by  the  general  public. 

This  device  (see  Fig.  381) 
is  a  cylindrical  copper  tank 
with  a  small  hose  attached, 
and  when  charged  weighs 
about  thirty-five  pounds. 
It  is  filled  with  water  in 
which  is  dissolved  some 
bicarbonate  of  soda,  while 
in  a  glass  container,  kept 
separate  from  the  soda  solu- 
tion, is  some  sulphuric  acid. 


FIG.   381.  —  Chemical  Fire  Extinguisher. 


When  the  acid  and  the  soda  solution  are  mingled,  carbonic  acid 
gas  is  formed,  creating  considerable  pressure  and  propelling  the 


930         FIRE   PREVENTION   AND   FIRE   PROTECTION 

water  through  the  hose  with  great  force.  In  addition,  the  car- 
bonic acid  gas  is  a  non-supporter  of  combustion,  and,  when  car- 
ried along  with  the  water,  helps  to  extinguish  the  fire,  a  result  to 
which  the  sodium  salts  in  the  solution  also  contribute. 

Years  of  experience  with  carbonic  acid  gas  devices  demonstrate 
beyond  question  that  when  these  are  intended  for  use  by  inex- 
perienced persons,  three  requirements  are  necessary.  First,  that 
the  machine  shall  operate  by  simply  turning  it  upside  down; 
second,  that  the  acid  shall  be  fed  gradually;  and  third,  that  the 
machine  shall  withstand  the  pressures  generated  with  a  large 
margin  of  safety.  Poorly  constructed  machines,  or  a  defective 
or  complicated  method  of  combining  the  acid  and  the  soda  solution, 
are  liable  to  render  the  extinguisher  worthless  at  a  time  when  every 
dependence  is  placed  on  it.  For  this  reason  it  becomes  necessary, 
in  the  interest  not  only  of  the  fire  insurance  community  but  of 
the  insuring  public  as  well,  to  establish  a  standard  of  safety  and 
reliability. 

Approved  Makes.  —  Standard  chemical  fire  extinguishers,  as 
recognized  by  insurance  interests,  are  those  makes  which  have 
been  tested  and  approved  by  the  Underwriters'  Laboratories,  Inc. 
The  latest  approved  list  of  such  extinguishers  may  be  had  by 
addressing  the  Underwriters'  Laboratories,  Inc.,  Chicago,  111.,  or 
the  National  Fire  Protection  Association,  87  Milk  St.,  Boston, 
Mass.  Each  approved  extinguisher  should  contain  the  label  of 
the  Underwriters'  Laboratories,  together  with  its  trade  name,  the 
name  of  the  manufacturer,  and  directions  for  use  and  maintenance. 

Specifications  for  Installation  and  Maintenance.*  —  Approved 
3-gallon  chemical  fire  extinguishers  may  be  used  instead  of  one- 
half  the  required  number  of  fire  pails,  as  previously  stated  in 
paragraph  "Substitutes" 

Setting.  —  A.  Shelves,  brackets  or  hooks  are  the  approved 
setting,  but  they  must  be  intended  for,  and  limited  in  their  use 
to,  extinguishers.  If  hooks  are  used,  the  extinguisher  must  be 
supported  at  the  bottom  as  well  as  at  the  top.  Extinguishers 
placed  on  the  floor,  on  stock  shelves,  window  sills,  safe,  desks, 
radiators,  boxes  or  on  work  tables,  will  not  be  approved. 

B.  To  be  not  lower  than  two  feet  above  the  floor,  measured 
from  floor  to  bottom  of  extinguisher. 

C.  To  be  not  higher  than  five  feet  above  the  floor,  measured 
from  floor  to  top  of  extinguisher. 

Location.  —  In  placing  extinguishers,  it  is  necessary  that 
they  be  placed  near  exits,  such  as  stairways,  elevators  and 

*  Practice  of  New  York  Fire  Insurance  Exchange. 


SIMPLE   PROTECTIVE    DEVICES,  ETC.  931 

fire  escapes  (preferably  in  stairway  halls  or  enclosures),  in  order 
that,  in  case  of  fire,  the  person  who  uses  them  may  do  so  from  a 
place  of  safety  and  with  means  of  escape  provided.  After  the 
exits  have  been  covered,  other  extinguishers  may  be  distributed 
at  central  points  in  the  space  they  are  intended  to  protect,  prefer- 
ence being  given  to  points  in  close  proximity  to  places  where 
fire  is  likely  to  start,  and  to  familiar  places  within  constant  sight 
of  occupants.  In  all  cases  they  must  be  in  a  clear  space,  pro- 
viding free  and  unimpeded  access,  and  must  not  be  blocked  by 
stock  or  machinery,  or  covered  with  rubbish  or  other  materials. 

Maintenance.  —  Extinguishers  should  be  tested  and  exam- 
ined once,  and  preferably  twice  a  year,  frequent  tests  being  in- 
valuable in  the  knowledge  they  give  employees  and  other  persons 
of  the  operation  of  the  device.  At  these  tests  the  extinguisher 
should  be  discharged  as  if  for  actual  service,  and  then  examined 
for  corrosion  of  the  interior  or  other  defects.  After  the  tests,  or 
whenever  used,  the  extinguisher  should  be  cleaned  and  recharged. 
To  recharge  an  extinguisher,  the  cap  should  be  unscrewed,  the 
acid  bottle  removed,  and  any  remaining  contents  emptied  from 
the  tank  and  from  the  bottle.  Then  both  tank  and  bottle  should 
be  thoroughly  rinsed  with  fresh  water,  and  any  deposit  removed 
from  the  wire  screen  over  the  hose  outlet. 

Charge.  —  The  soda  charge  is  prepared  by  mixing  one  pound 
and  a  half  of  bicarbonate  of  soda  in  two  and  one-half  gallons  of 
water  and  stirring  until  the  soda  is  dissolved,  when  the  solution 
can  be  poured  in  the  tank,  care  being  taken  that  it  does  not  rise 
above  the  filling  mark  indicated  on  the  inside  of  the  tank. 

The  acid  charge  consists  of  4  fluid  ounces  of  commercial 
sulphuric  acid  (oil  of  vitriol),  which,  when  poured  in  the  bottle, 
should  not  rise  above  the  filling  mark  indicated  on  the  bottle. 
If  the  bottle  has  no  filling  mark,  the  acid  should  fill  not  more  than 
half  the  bottle. 

When  the  lead  stopper  has  been  put  in  the  bottle,  it  can  be 
replaced  in  the  bottle  holder  and  the  latter  put  in  position  in  the 
tank.  In  replacing  the  cap,  the  washer  must  not  be  omitted; 
the  cap  should  be  screwed  down  tight  and  cross  threading  avoided. 
After  recharging,  the  date  and  the  signature  of  the  person  who 
performed  'it  should  be  recorded  on  the  card  or  tag  attached  to 
the  machine  for  that  purpose. 

Extinguishers  should  not  be  exposed  to  a  temperature  of 
32°  F.  or  lower  (unless  filled  with  non-freezing  solution). 

In  Case  of  Fire.  —  Extinguishers  should  be  carried  to  the 
fire  right  end  up,  and  to  be  used,  should  be  tipped  upside  down. 
This  action  automatically  starts  the  stream,  which  can  be  shut 
off  by  righting  the  extinguisher.  If  the  extinguisher  fails  to  work 
at  once,  or  the  stream  has  not  sufficient  force,  a  vigorous  shaking 
will  usually  remedy  the  matter.  While  the  stream  is  more  effec- 
tive if  used  close  to  the  fire,  in  case  of  necessity  it  can  be  directed 
from  a  distance  as  great  as  25  feet.  The  stream  should  always 
be  directed  first  at  the  lowest  part  of  a  fire  and  then  worked  up- 
ward. The  use  of  the  extinguisher  is  especially  recommended 
for  the  following  kinds  of  fires: 


932         FIRE   PREVENTION   AND   FIRE   PROTECTION 

Inaccessible  fires  in  hidden  places,  between  floors,  ceilings 
and  partitions,  and  in  chimneys,  flues  and  shafts. 

In  enclosed  spaces,  such  as  closets,  boxes,  etc. 

Overhead  fires,  such  as  draperies,  curtains,  hangings,  decora- 
tions, etc. 

Supervision.  —  The  extinguishers  must  be  placed  in  charge 
of  the  engineer,  the  janitor,  the  foreman,  the  watchman  or  some 
person  with  authority,  who  will  be  answerable  for  their  efficiency. 

Special  Hazards.  — 

In  risks  or  parts  of  risks  occupied  for  any  of  the  hazards 
or  processes  enumerated  below,  water  pails  and  carbonic  acid  gas 
hand  fire  extinguishers  cannot  be  accepted  as  ground  for  allow- 
ance in  rating,  but  instead  thereof  pails  containing  sand,  or  any 
make  of  hand  fire  extinguisher  of  one  quart  or  more  capacity 
which  has  been  approved  by  the  Underwriters'  Laboratories  for 
use  in  incipient  fires  in  materials  where  water  or  solutions  con- 
taining large  percentages  of  water  are  not  effective,  and  which 
bears  the  label  of  said  Laboratories,  may  be  accepted,  in  place  of 
equal  numbers  of  water  pails  or  carbonic  acid  gas  hand  fire  ex- 
tinguishers respectively;  except  that  where  the  hazards  or  pro- 
cesses so  protected  are  enclosed  in  rooms,  not  less  than  six  sand 
pails  or  one  such  approved  extinguisher  shall  be  required  in  each 
room,  however  small  its  area,  such  pails  or  extinguishers  not 
to  be  credited  upon  the  protection  of  the  premises  outside  such 
room. 

The  hazards  and  processes  subject  to  this  ruling  are  as  follow: 

Automobile  Garages.  Rendering  Establishments. 

Benzine  Dyeing  and  Cleaning  Soap  Works. 

Establisments,  having  5  gal-  Telephone  and  Telegraph  Ex- 
Ions  or  over  of  benzine.  change  and  Stations. 

Car  Barns.  Varnish  Works. 

Degreasing  Plants.  Window    Shade    Manufactur- 

Electric  Light  and  Power  Sta-  ing. 

tions.  All  risks   in  which  calcium 

Grease  risks.  carbide,   peroxide    of   sodium, 

Heating    of    oil,    wax,    pitch,  lime,    paints,    oils,    varnishes, 

asphalt,  rosin,  etc.  japans,  lacquers,  volatile  fluids, 

Paint  Works.  rubber     cement,     are     either 

Rubber   Cement  Manufactur-  stored  or  are  used  in  the  pro- 

ing.  cess  of  manufacturing.* 

Large  Capacity  Chemical  Extinguishers.  —  In  premises 
where  there  is  no  water  supply,  or  where  a  high  pressure  service 
from  the  mains  is  not  available,  large  capacity  chemical  extin- 
guishers may  be  made  a  valuable  means  of  fire  protection.  These 
may  be  fixed,  in  the  shape  of  large  tanks  arranged  to  discharge 
through  standpipes  and  hose  connections,  or  portable  on  wheels. 
*  New  York  Fire  Insurance  Exchange,  Circular  of  January  2,  1912. 


SIMPLE   PROTECTIVE    DEVICES,  ETC.  933 

Specifications  for  the  construction  and  installation  of  the  former 
type  may  be  obtained  from  the  National  Board  of  Fire  Under- 
writers. Tests  made  with  a  fixed  tank  of  125  gallons  capacity  are 
described  in  the  British  Fire  Prevention  Committee's  "Red 
Book"  No.  131.  The  tests  were  partly  automatic,  by  means  of 
sprinkler  heads,  and  partly  manual  by  means  of  valve  and  hose. 

A  variety  of  the  portable  type  is  a  40-gallon  " engine,"  capable 
of  throwing  a  stream  about  75  feet,  the  discharge  lasting  about 
six  minutes.  When  not  in  use,  the  tank  stands  vertically,  with 
handles  in  air,  occupying  a  space  less  than  four  feet  square.  The 
charge  consists  of  20  pounds  of  bicarbonate  of  soda  and  7  pounds 
of  sulphuric  acid,  applied  as  for  hand  chemical  extinguishers, 
previously  described.  This  type  of  engine  i$  very  valuable  for 
country  properties,  where  a  number  of  buildings,  such  as  residence, 
stable,  garage,  and  farm-  or  out-buildings,  are  to  be  protected. 

Tests  of  Fire  Pails,  Extinguishers,  etc.  —  A  considerable 
number  of  actual  tests  of  the  efficacy  of  water  pails,  hand-pumps, 
and  chemical  fire  extinguishers,  etc.,  have  been  made  by  the  British 
Fire  Prevention  Committee. 

As  to  fire  pails  vs.  extinguishers,  the  Chairman  of  the  Executive 
Committee,  Mr.  Edwin  O.  Sachs,  finds  as  follows: 

These  tests  (fire  pails  and  hand-pumps)  were  undertaken 
with  a  view  of  arriving  at  data,  which,  if  compared  with  those 
obtained  in  identical  or  similar  tests  in  which  hand  chemical 
fire  extinguishers  are  used,  would  allow  of  the  relative  value  of 
the  various  types  of  first  aid  appliances  being  more  properly 
realized  than  is  generally  the  case. 

The  chemical  fire  extinguisher  (containing  2  to  3  gallons  of 
liquid),  if  so  constructed  that  it  can  be  readily  and  easily  handled 
by  parties  not  conversant  with  its  action  or  peculiarities,  has 
considerable  advantage,  assuming  of  course  that  it  is  in  a  proper, 
workable  and  clean  condition. 

But  it  should  not  be  forgotten  that  the  ordinary  bucket  of 
water  and  the  hand-pump  have  a  very  high  fire  extinguishing 
efficiency. 

Thus,  the  advent  of  the  hand  chemical  fire  extinguisher 
should  by  no  means  imply  neglect  of  the  humbler  and  simpler 
extinguishing  appliances.* 

Detailed  and  illustrated  reports  of  tests  with  various  English 
pattern  chemical  fire  extinguishers  may  be  found  in  the  British 
Fire  Prevention  Committee's  "Red  Books"  Nos.  121,  126,  134, 

*  See  British  Fire  Prevention  Committee's  "Red  Book"  No.  128,  "Fire 
Tests  with  Buckets  of  Water,  Hand  Pumps,  etc.,  as  in  Common  Use." 


934         FIRE    PREVENTION    AND    FIRE    PROTECTION 

142  and  152.     The  introductory  "Note"  to  one  of  these  reports 
will,  perhaps,  give  a  fair  resume  of  the  tests : 

This  series  of  tests  with  chemical  fire  extinguishers  again 
showed  that  hand  chemical  fire  extinguishers,  as  a  class,  can  be 
employed  with  advantage  in  the  incipient  stages  of  small  fires. 
If  a  fire  has  obtained  such  proportions  that  it  cannot  be  extin- 
guished by  chemical  hand  fire  extinguishers,  still  they  may  be  use- 
ful to  keep  it  in  check  until  larger  fire  appliances  can  be  brought 
into  play  —  this  applies  especially  to  loose  material.* 

Fire  Tests  with  Liquid  Petroleum  Products.  —  A  series 
of  valuable  experimental  tests  has  been  carried  out  by  the  British 
Fire  Prevention  Committee  to  determine  the  efficiency  of  chemical 
fire  extinguishers  and  other  simple  means  in  the  extinguishment 
of  burning  "  petrol >J  or  gasolene,  etc.  These  tests  are  of  especial 
interest  to  such  trades  as  cleaners  and  dyers,  where  volatile  spirits 
are  employed,  and  to  those  interested  in  fire  safety  as  applied  to 
automobiles,  garages,  motor  boats,  etc. 

"Red  Book"  No.  136  describes  23  tests  made  to  determine  the 
effects  of  a  chemical  fire  extinguisher  upon  petrol  burning  in  small 
open  tanks  and  in  other  receptacles  of  varying  size,  including  a 
trough  covered  with  a  grating  (approximating  the  conditions  exist- 
ing in  the  bottom  of  a  motor  boat),  and  over  a  large  unbroken 
area,  such  as  the  stone  floor  of  a  motor  garage. 

The  extinguishers  used  were  of  a  patented  English  type,  of 
varying  capacity,  but  all  very  similar  in  appearance  to  our  "Un- 
derwriters" chemical  extinguisher.  The  tank  contained  tetra- 
chloride,  the  pressure  being  supplied  by  carbonic  acid  gas  contained 
in  a  small  steel  cylinder  attached  to  the  side  of  the  main  tank 
and  connected  therewith  by  a  valve.  The  following  is  a  summary 
of  the  results  of  the  tests: 

The  extinguisher  was  effective  on  small  petrol  fires  of  con- 
siderable severity.  In  19  tests  and  re-tests  out  of  23,  the  extin- 
guishers were  effective.  In  14  out  of  19  instances  the  fire  was 
out  in  70  seconds  or  under. 

Its  efficiency  was  not  entirely  dependent  on  the  actual 
mechanical  application  of  its  contents  into  the  burning  liquid, 
but  was  largely  due  to  chemical  action.  The  appliance  was  not 
simple  to  operate,  and  in  every  case  the  application  of  the  liquid 
from  the  extinguisher  upon  or  over  the  burning  petrol  caused 
black  pungent  smoke  to  rise  which  was  occasionally  of  such  a 
character  and  density  as  to  hinder  the  operation  of  extinguish- 
ing. 

*  "  Red  Book  "  No,  126,  "  Fire  Tests  with  Fire  Extinguishers." 


SIMPLE   PROTECTIVE    DEVICES,  ETC.  935 

The  tests  took  place  in  the  open.  Most  of  them  would  have 
been  almost  impossible  to  carry  out  in  a  confined  space. 

"Red  Book"  No.  143  describes  22  tests  of  a  character  similar 
to  those  previously  described.  The  extinguisher  used  is  known 
as  the  "Foam"  petrol  extinguisher,  which,  upon  being  inverted, 
causes  the  mixing  of  an  acid  with  a  special  alkali  solution,  forming 
a  foam.  In  his  introductory  "Note,"  Mr. Percy  Collins  states  that 

These  tests  were  of  a  very  interesting  nature,  more  especially 
so  as  showing  the  effect  of  employing  a  thick  foam  to  cut  the 
burning  vapor  off  from  the  petrol,  and  to  deprive  the  surface  of 
the  latter  of  contact  with  the  air. 

From  past  experience  and  records  one  must  realize  that  for 
petrol  fires  of  any  magnitude  this  extinguisher  would  be  useless, 
but  for  comparatively  small  fires,  and,  it  may  be,  even  in  the 
early  stages  of  comparatively  big  ones,  it  can  be  operated  with 
advantage,  especially  where  its  contents  can  be  directed  against 
a  hard  surface  —  vertical  preferred  —  so  as  to  allow  of  the  foam 
falling  on  to  the  surface  of  the  petrol  and  floating  over  it. 

In  19  tests  out  of  a  total  of  22  the  extinguisher  was  effective, 
and  in  13  instances  the  fire  was  out  in  one  minute  or  under.  Un- 
like the  previously  described  tests,  the  efficiency  of  this  extinguisher 
appeared  to  be  dependent  upon  the  actual  mechanical  application 
of  the  contents  to  a  surface,  the  force  of  the  contact  adding  con- 
siderably to  the  amount  of  foam  produced,  which  floated  over  the 
burning  liquid  and  excluded  the  oxygen  in  the  air. 

"Red  Book"  No.  133  describes  25  tests  of  burning  benzine  in 
a  rinsing  tank  and  on  a  scrubbing  table  (both  as  used  by  dyers 
and  cleaners),  —  of  crates  of  loose  wool,  heaps  of  oily  rags  and 
dirty  cotton  waste,  —  of  burning  petrol  in  vessels  of  various  shapes 
and  capacities,  —  and  of  burning  celluloid.  The  means  of  extin- 
guishment employed  were  asbestos  cloths  (squares  of  asbestos 
cloth,  6  ft.  by  6  ft.  4  ins.  in  size,  about  •$•%  in.  thick,  known  as 
"Lucifer  Brand"  Fire  Sheets),  sand,  and  steam.  The  following 
is  a  brief  summary  of  the  tests: 

The  tests  demonstrated  the  complete  efficiency  of  asbestos 
cloths  in  putting  out  burning  spirit  vapor. 

In  the  case  of  burning  materials  it  was  demonstrated  that 
asbestos  cloths  could  be  of  use  in  confining  the  fire  until  other 
appliances  were  brought  into  play. 

The  efficiency  of  sand  was  demonstrated  where  it  can  be 
employed  to  soak  up  spirit,  the  vapor  of  which  is  ignited. 

The  efficiency  of  steam,  as  applied,  was  demonstrated  where 
a  building  in  which  the  fire  is  burning  can  be  closed  up,  so  as  to 
exclude  as  much  draught  as  possible. 


936         FIRE    PREVENTION    AND    FIRE    PROTECTION 

In  his  introductory  "Note,"  Mr'.  Percy  Collins  stated  as  follows: 

The  tests  here  reported  were  of  a  most  interesting  character. 

The  application  of  the  asbestos  cloths  was  certainly  effective, 
and  fully  demonstrated  their  great  utility  in  subduing  fires  caused 
by  spirit  vapor.  They  showed  that  where  trade  processes  need 
the  employment  of  a  volatile  spirit,  these  asbestos  cloths  form  a 
most  valuable  first-aid  appliance. 

As  to  the  use  of  sand  (which  was  applied  in  one  case),  its 
value  was  also  shown,  but  further  tests  should  be  carried  out. 

With  respect  to  the  employment  of  steam  —  the  effect  of 
this  was  most  marked.  While  there  was  plenty  of  ventilation  in 
the  upper  part  of  the  walls  of  the  hut,  to  correspond  with  what 
would  be  arranged  for  in  buildings  occupied  for  processes  of 
manufacture  requiring  the  use  of  volatile  spirit,  the  steam,  never- 
theless, quickly  diffused  throughout  the  hut  and  quenched  the 
fire.  It  is,  however,  important  that  the  amount  of  steam  avail- 
able should  bear  a  suitable  relation  to  the  cubic  contents  of  the 
room  or  rooms  to  be  protected. 

Dry  Powder  Fire  Extinguishers.  —  The  efficiency  or  rather 
the  inefficiency  of  tubes  or  so-called  fire  extinguishers  containing 
dry  powder  mixtures  instead  of  liquids  was  first  brought  to 
prominent  notice  through  the  Iroquois  Theatre  fire.  The  un- 
successful attempts  made  to  check  the  fire  in  its  incipient  stage  by 
means  of  "Kilfyre"  dry  powder  tubes  led  Mr.  John  R.  Freeman, 
then  president  of  the  American  Society  of  Mechanical  Engineers, 
to  investigate  such  extinguishers  thoroughly  in  connection  with 
his  presidential  address  in  1905  on  "The  Safeguarding  of  Life  in 
Theatres."*  In  that  paper  Mr.  Freeman  gave  several  analyses 
of  the  chemical  constituents  of  such  compounds,  showing  that  they 
were  all  composed  of  bicarbonate  of  soda  (or  cooking  soda),  com- 
bined with  small  varying  percentages  of  coloring  matter  and  some 
substance,  such  as  starch  or  clay,  to  prevent  the  caking  of  the 
powder.  The  conclusion  was  reached  that  "the  material  has  some 
small  value  for  a  certain  class  of  fires,"  but  "dry  powder  fire  extin- 
guishers should  never  be  used  to  give  a  false  sense  of  security  about 
the  stage  of  a  theatre,"  nor  for  factory  fire  protection.  "Pails  of 
water  are  far  more  reliable." 

Later  experiments  with  similar  dry  powder  fire  extinguishers 
have  been  made  by  the  Underwriters'  Laboratories,  Inc.,  and  by 
the  British  Fire  Prevention  Committee. 

Underwriters'  Laboratories  Tests.  —  The  investigations  of  this 
organization  were  printed  in  Bulletin  No.  125  of  the  National  Fire 

*  See  Vol.  XXVII  of  Transactions,  American  Society  Mechanical  Engineers. 


SIMPLE   PROTECTIVE   DEVICES,  ETC.  937 

Protection     Association     (December,     1906).     The     conclusions 
reached  were  as  follows: 

(1)  Chemical  Analyses: 

Chemical  analyses  of  the  contents  of  a  number  of  tubes  from 
various  manufacturers  show  that  th'ey  contain  mixtures  of  bi- 
carbonate of  soda  and  silica,  and.  generally,  oxide  of  iron.  Bi- 
carbonate of  soda  is  the  principal  constituent,  running  85  per  cent, 
to  98.4  per  cent.  A  typical  analysis  is: 

Sodium  bi-carbonate 87. 6% 

Iron  oxide 4. 0% 

Silica 8.4% 

100.0% 

Sodium  bi-carbonate,  when  heated  sufficiently,  gives  off 
carbon  dioxide  and  is  converted  into  sodium  carbonate.  The 
pure  bi-carbonate  theoretically  gives  26.7%  carbon  dioxide  and 
63%  sodium  carbonate.  The  latter  compound  is  very  stable, 
fusing  at  a  bright  red  heat,  at  which  temperature  it  gives  up 
about  1%  carbon  dioxide. 

It  must  be  noted,  in  this  connection,  that  when  soda  is 
thrown  on  a  fire,  if  the  evolved  carbon  dioxide  has  any  effect  at 
all  it  is  limited  considerably,  since,  when  the  temperature  is 
lowered,  the  evolution  of  gas  stops,  and  to  effect  further  decom- 
position of  the  soda  requires  a  considerably  higher  temperature 
than  at  the  start. 

The  oxide  of  iron  and  silica  are  intended  to  prevent  caking 
of  the  bi-carbonate,  which  has  the  property  of  absorbing  moisture 
from  the  air.  On  examination  of  thirty-one  tubes  of  various 
makes,  stored  since  1903-1904  in  a  basement  protected  from  the 
weather,  it  was  found  that  eleven  (11)  were  caked  to  such  an 
extent  as  to  prevent  their  use. 

(2)  Fire  Test: 

Tests  were  made  to  determine  the  practical  efficiency  of  these 
extinguishers  applied  to  (a)  burning  liquids,  and  (6)  solid  sub- 
stances of  the  nature  of  wood. 

November  13,  1906.  Temperature  58  degrees  Fahr.  Wind 
7  miles  per  hour.  Laboratory  yard. 

(a)  Gasolene  was  spread  on  a  surface  of  wood  4  ft.  X  7  ft., 
and  allowed  to  burn  five  seconds.  It  required  three  tubes  to 
subdue  the  blaze,  which  flared  up  within  a  few  seconds.  A 
sufficient  quantity  of  powder  was  added  to  cover  completely  the 
whole  surface,  but  in  this  case  the  gasolene  burned,  apparently 
not  being  retarded  in  the  least.  If  any  carbon  dioxide  was 
evolved  it  had  no  appreciable  effect. 

I"  wood       "1    was  placed  in  a  heap,  3  ft. 

CM   A  mivtnrp  nf  J  ^y  L  hiSh  and  3  ft-  sQuare  at  the 

1  shavings  f  base.     This  fire  was  allowed 
(^  excelsior  J    to  burn  three  minutes,  when 

the  contents  of  nine  tubes  were  thrown  on  it  in  rapid  succession. 
The  fire  was  retarded  to  some  extent,  but  in  four  minutes  was 


938         FIRE    PREVENTION    AND    FIRE    PROTECTION 

burning  rapidly  again,  although  covered  with  the  powder.  This 
fire  was  finally  completely  extinguished  with  one  of  the  approved 
3-gallon  liquid  hand  chemical  extinguishers. 

The  British  Fire  Prevention  Committee's  Tests  with  dry  powder 
fire  extinguishers  have  been  quite  exhaustive.  In  one  of  their 
reports  (see  "Red  Book"  No.  127,  issued  1908)  the  results  of  30 
tests  are  given,  showing  the  effects  of  an  English  patented  dry 
powder  extinguisher  on  a  burning  dressing  table  in  a  bedroom 
with  curtains,  on  burning  hay  in  a  stable  rack,  burning  crates, 
packing  cases,  loose  rubbish,  celluloid  and  gasolene.  The  follow- 
ing is  a  brief  summary  of  the  tests: 

The  tests  demonstrated  that  the  extinguishers,  when  prop- 
erly handled  and  in  sufficient  number,  were  efficient  in  checking 
small  fires  in  their  early  stages. 

Where  the  material  ignited  was  soft  and  loose,  difficulty  was 
always  apparent  in  stopping  the  smouldering  which  ensued. 

Where  petrol  (gasolene)  or  petrol  vapor  was  ignited  over  a 
small  area  (not  exceeding  4  sq.  ft.)  the  extinguishers  were  uni- 
formly effective. 

The  efficiency  depended  materially  on  the  closeness  of  range, 
the  position  of  the  operator's  shoulder  being  above  the  seat  of 
fire,  and  dexterity  in  throwing  the  powder. 

Conclusions.  —  The  various  tests  enumerated  above  would  seem 
to  show  conclusively  that,  for  all  ordinary  locations  and  fire  emer- 
gencies, water  pails,  chemical  fire  extinguishers  or  hand  hose,  etc., 
are  a  far  more  reliable  means  of  first  aid  than  dry  powder  estin- 
guishers.  There  are,  however,  certain  conditions  under  which 
dry  powder  extinguishers  may  be  desirable,  at  least  as  a  secondary 
if  not  primary,  means  of  protection.  Such  conditions  would 
include  locations  where  extremely  low  temperatures  are  liable  to 
occur  (thus  making  possible  or  probable  the  freezing  of  pails  or 
chemical  extinguishers,  even  when  filled  with  so-called  non-freezing 
mixtures),  —  museums  or  libraries,  where  water  damage  might 
be  as  serious  as  fire  damage,  —  the  burning  of  inflammable  liquids, 
where  water  would  only  serve  to  spread  the  flames,  —  or  in  elec- 
trical apparatus,  where  the  application  of  water  to  fire  would  serve 
to  cause  a  "  short  circuit,"  etc. 

Fire-retarding  Paints.  —  So-called  "fireproof"  paints,  or 
the  cold  water  compounds  which  are  sold  under  a  variety  of  trade 
names,  all  claiming  fire-resisting  properties,  should  be  classed  as 
fire-retard  ants  rather  than  as  fireproof.  While  wood  or  other  com- 
bustible materials  which  have  been  coated  with  such  compounds 


SIMPLE   PROTECTIVE    DEVICES,  ETC.  939 

will  successfully  withstand  the  blaze  of  a  match,  a  few  minutes 
exposure  to  a  greater  heat,  as  of  a  lamp,  .will  show  that  no  great 
degree  of  fire-resistance  exists.  However,  the  preventive  value  of 
such  coatings  is  material,  especially  for  scenery,  properties,  and 
other  stage  fittings,  in  that  the  quick  spread  or  " flash"  of  fire  over 
such  materials  will  be  greatly  retarded,  if  not  altogether  prevented. 
The  use  of  fire-retarding  paints  or  solutions  is,  therefore,  to  be 
strongly  recommended  for  scenery,  etc.,  whether  required  by  law 
or  not.  Some  cities,  notably  New  York,  require  "  all  stage  scenery, 
curtains  and  decorations  made  of  combustible  material,  and  all 
woodwork  on  or  about  the  stage  to  be  painted  or  saturated  with 
some  non-combustible  material,  or  otherwise  rendered  safe  against 
fire." 

Acceptance  of  treatment  depends  on  tests  made  by  the  Bureau 
of  Buildings  on  the  materials  in  each  individual  case. 

For  fabrics,  scenery  and  the  wood  frames  for  same,  there  must 
be  no  flame  or  glow  after  the  application,  for  fifteen  seconds,  of 
the  flame  of  an  ordinary  alcohol  lamp  or  torch. 

For  paints,  the  following  regulations  are  made : 

First.  —  The  term  fireproof  paint  shall  be  understood  to 
mean  any  preparation  used  to  cover  the  surfaces  of  wood  or  other 
materials  for  the  purpose  of  protecting  the  same  against  ignition. 

Second.  —  No  fireproof  paint  will  be  considered  satisfactory 
unless  it  so  protects  the  wood  or  other  material  to  which  it  is 
applied  that  the  same  will  not  flame  or  glow  after  having  been 
subjected  to  the  flame  of  a  gasolene  torch  for  two  minutes. 

Third.  —  Before  applying  fireproof  paint  to  any  material  the 
surfaces  must  be  cleaned. 

Fourth.  —  Application  of  fireproof  paint  must  be  repeated 
whenever  it  is  found  that  the  material  to  which  it  is  applied  is  no 
longer  protected  to  fulfil  Specification  No.  2. 

Application  by  hand  brush  is  preferable  to  the  use  of  a  spraying 
machine. 

A  systematic  effort  has  been  made  in  Paris  to  render  scenery 
less  flammable,  and,  both  in  the  National  Opera  House  and  in 
the  theatres  visited,  the  official  test  marks  (with  dates)  were 
observable  on  all  scenery,  stamped  in  plain  black  letters  on  the 
back.  The  manner  of  rendering  the  scenery  less  flammable  is 
left  to  the  theatre  owners,  whose  scenery,  however,  has  to  be 
inspected  annually  to  the  satisfaction  of  the  authorities.  A  use- 
ful guide  has,  however,  been  issued  on  the  subject  by  the  Paris 
Municipal  Laboratory.  This  guide  contains  the  following 
recommendations  : 

Wood  should  be  impregnated  thoroughly  to  render  it  non- 
inflammable,  and,  failing  this,  should  be  covered  with  two  coats 


940        FIRE    PREVENTION    AND    FIRE    PROTECTION 

of  solution  applied  at  intervals.  The  most  suitable  solution  for 
the  impregnation  is  the  following: 

Ammonium  phosphate  100  gr.,  boracic  acid  10  gr.,  water 
1000  gr.  The  following  formula  may  be  used  for  coating,  but 
gives  somewhat  inferior  results: 

i  Ammonium  sulphate  135  gr.,  borax  15  gr.,  boric  acid  5  gr., 
water  1000  gr.  When  the  applications  are  made  by  coating,  at 
least  two  coatings  are  necessary.* 

Fire-retarding  paints  are  generally  compounded  under  secret 
formulas,  comprising  the  use  of  some  chemical,  such  as  sodium 
salts,  gypsum  and  the  silicates,  to  form  a  non-inflammable  mineral 
coating,  combined  with  a  binder  such  as  casein  or  glue.  Frequent 
renewals  are  necessary  to  insure  efficiency. 

Whitewash  so  well  meets  the  requirements  of  this  class  that 
we  print  formula  recommended  by  the  Lighthouse  Board  of  the 
United  States  Treasury  Department  as  follows: 

Slake  one-half  bushel  of  unslaked  lime  with  boiling  water, 
keeping  it  covered  during  the  process;  strain  it  and  add  a  peck 
of  salt  dissolved  in  warm  water;  three  pounds  of  ground  rice, 
put  in  boiling  water  and  boil  to  a  thin  paste;  one-half  pound 
powdered  Spanish  whiting  and  a  pound  of  clelar  glue  dissolved 
in  hot  water;  mix  these  well  together  and  let  the  mixture  stand 
for  several  days.  Keep  the  wash  thus  prepared  in  a  kettle  or 
portable  furnace  and  when  used  put  it  on  as  hot  as  possible  with 
painter's  or  whitewash  brushes,  f 

Fire-retarding  Solutions.  —  The  great  value  of  being  able 
so  to  treat  textiles  by  means  of  simple  chemical  solutions  as  to 
render  them  non-inflammable  has  been  well  stated  by  Mr.  Ellis 
Marshland  in  his  introductory  note  to  The  British  Fire  Prevention 
Committee's  "Red  Book"  No.  129,  "Fire  Tests  with  Textiles" 
(1908). 

A  large  number  of  lives  are  lost  annually  owing  to  the  rapidity 
with  which  light  textiles  catch  and  spread  flame. 

An  extraordinary  number  of  people  also  meet  with  personal 
injury,  either  of  permanent  or  temporary  character  owing  to  the 
same  cause,  and  children  in  particular  are  sufferers,  especially 
the  children  of  the  poorer  classes. 

Any  effort  made  to  reduce  the  rapidity  of  spread  of  fire  in 
light  textiles  must  claim  careful  consideration,  and  equally  so, 
whether  the  means  proposed  of  lessening  the  risk  of  fire  com- 
prise the  use  of  proprietary  articles  or  the  use  of  [chemicals'  avail- 
able to  all. 

*  See  "Fire  Prevention  in  Paris,"  Journal  of  the  British  Fire  Prevention 
Committee,  No.  VIII,  1912. 

t  See  "Approved  Devices  and  Materials,"  listed  by  the  Underwriters' 
Laboratories,  Incorporated. 


SIMPLE   PROTECTIVE    DEVICES,  ETC.  941 

Chemicals  have  long  been  known  to  be  useful  in  obtaining 
non-flammability,  but  they  generally  present  difficulties  as  to 
their  use,  as  in  course  of  time  their  virtue  diminishes  and  unless 
the  treatment  is  renewed  there  is  a  sense  of  false  security. 

Some  simple  chemicals,  combined  in  a  form  which  can  be 
easily  and  frequently  used,  are  the  subject  of  this  report. 

The  chemicals  are  combined  in  such  a  manner  that  after  the 
ordinary  process  of  washing  has  taken  place,  they  will  either  pro- 
duce non-flammability  only,  or  where  the  goods  require  starching 
the  same  chemicals  will  produce  simultaneously  stiffness  as  well 
as  non-flammability. 

As  to  the  tests  the  report  speaks  for  itself,  and  an  appendix 
has  been  added,  indicating  how  the  treatment  should  be  applied. 
It  is  to  be  hoped  that  the  tests  undertaken  by  the  committee  may 
do  something  towards  reminding  managers  of  public  institutions, 
laundry  managers,  and  even  the  ordinary  householder  that  there 
are  means  available  for  reducing  the  fire  hazard  in  washable 
textiles. 

To  the  above  enumerated  uses  for  non-inflammable  textiles, 
mention  should  be  added  of  their  value  in  theatrical  productions, 
where  costumes,  draperies,  textile  properties,  and  even  light  scenic 
hangings,  etc.,  could  be  similarly  treated,  often  to  great  life-saving 
advantage. 

The  report  above  mentioned  comprised  some  72  tests  of  textiles 
such  as  flannelette,  calico,  chintz,  chiffon,  lace  and  madras  cur- 
tains. The  tests  were  made  to  note  the  effects  of  flame  upon 
textiles. 

(1)  untreated,  as  bought  in  open  market, 

(2)  untreated,  after  washing  in  an  ordinary  manner,  and 

(3)  after  being  washed  and  then  treated  with    the  chemical 
solution  under  test,  known  as  "Flameoff." 

The  materials  as  delivered  from  the  manufacturers  burnt 
rapidly  in-  all  tests. 

The  materials  as  washed  in  the  ordinary  way  burnt  rapidly 
in  all  tests. 

The  materials  as  washed  and  treated  with  "Flameoff" 
charred  only  in  69  tests,  and  burnt  slightly  in  3  tests,  out  of  a 
total  of  72  tests  conducted  with  57  portions  of  materials.* 

The  makers  of  "Flameoff  "  give  the  following  directions  for  use: 

DIRECTIONS  FOR  USE  FOR  PRODUCING  NON-INFLAMMABILITY  AND 
STIFFNESS. 

Pour  one  quart  of  boiling  water  quickly  over  the  contents  of 
a  box  of  " Flameoff;"  stir  the  mixture  until  every  particle  is 
thoroughly  dissolved. 

*  Summary  of  tests,  "Red  Book"  No.  129. 


942         FIRE   PREVENTION   AND   FIRE   PROTECTION 

The  article  to  be  treated  with  "FlameorT"  must  be  thoroughly 
dry. 

Soak  it  by  covering  it  well  with  the  hot  mixture,  place  a  lid 
over  it  and  leave  until  quite  cold. 

Wring  the  article  out  lightly;  hang  it  up  to  dry,  and  iron  in 
the  usual  way. 

The  iron  must  only  be  moderately  hot  to  prevent  scorching. 

Never  mix  more  "Flameoff"  than  you  require  at  one  time. 

DIRECTIONS  FOR  USE  FOR  RENDERING  ARTICLES  NON-INFLAM- 
MABLE ONLY. 

Suitable  for  Bed  Linen,  Pillow  Cases,  Sheets,  Blankets, 
Nightdresses,  Flannelette,  Table  Linen,  Lace  Work,  Blinds, 
Bed  Curtains,  Furniture  Covers,  etc. 

Pour  one  quart  of  hot  (not  boiling)  water  quickly  over  the 
contents  of  a  box  of  "Flameoff";  stir  the  mixture  until  every 
particle  is  thoroughly  dissolved. 

,  The  article  to  be  treated  with  "Flameoff"  must  be  thor- 
oughly dry. 

Soak  it  by  covering  it  well  with  the  hot  mixture,  place  a  lid 
over  and  leave  it  until  quite  cold. 

Rinse  the  article  well  in  the  mixture  and  wring  it  out  lightly ; 
hang  it  up  to  dry,  and  iron  in  the  usual  way. 

The  iron  must  only  be  moderately  hot  to  prevent  scorching. 

Never  mix  more  "Flameoff"  than  you  require  at  one  time. 

The  above  mentioned  tests  proved  so  convincing  as  to  the  value 
of  such  treatment  for  textiles  under  certain  conditions  that  later 
experiments  (see  "Red  Book"  No.  148,  1910)  were  undertaken 
by  the  British  Fire  Prevention  Committee,  to  secure  data  as  to 
rendering  textiles  permanently  inflammable,  and  to  secure  data 
as  to  some  simple  method  by  which  the  relative  fire-resistance  of 
such  treated  textiles  could  be  determined.  In  this  second  series 
no  less  than  456  samples  of  flannel,  flannelette  and  union  (i.e., 
mixture  of  cotton  and  wool)  were  tested,  some  treated  and  some 
untreated.  From  these  tests  the  committee  decided  that  textiles 
intended  to  be  permanently  non-inflammable  can  only  obtain 
classification  as  "  non-flaming "  when  fulfilling  the  conditions  of 
the  following  test: 

(a)  Three  treated   samples,    comprising  each    (about)   one 
square  yard  of  the  material  to  be  tested,  shall  be  washed  with 
soap  and  water  and  ironed  ten  times. 

(b)  The  samples  shall  be  ironed  once  (in  addition)  with  an 
ordinary  household  iron  within  three  hours,  but  not  less  than  one 
hour  before  the  test  and  shall  be  dry  to  the  touch  immediately 
before  testing. 

(c)  The  samples  thus  prepared  shall  be  measured  exactly  and 


SIMPLE    PROTECTIVE   DEVICES,  ETC.  943 

their  areas  shall  not  vary  more  than  10  per  cent,  above  or  below  a 
square  yard. 

(d)  The  samples  shall  be  suspended   in  rotation  from   a 
wooden  lath,  vertically,  by  three  tacks,   clips  or  other  metal 
fastenings. 

(e)  Fire  shall  be  applied  at  the  center  of  the  bottom  edge 
from  a  taper  J-in.  diameter,  not  more  than  12  ins.  or  less  than 
6  ins.  long. 

(f)  The  lighted  end  of  the  taper  shall  be  held  at  the  edge  for 
not  less  than  fifteen  seconds  or  more  than  thirty  seconds. 

(g)  If  not  more  than  5  per  cent,  of  the  area  actually  under  tesi 
burns  within  sixty  seconds,  when  taken  on  the  average  of  three 
samples,  the  material  shall  be  classified  as  " non-flaming." 

NOTE.  —  Where  the  treatment  is  not  intended  to  withstand 
washings,  but  requires  renewal  after  every  washing,  the  same 
test  should  be  applied,  but  no  washings  or  ironings  under  (a) 
would  be  required,  and  the  classification  would  only  have  bearing 
upon  the  efficiency  of  the  individual  treatment  and  not  upon  its 
capacity  to  withstand  the  effects  of  washings. 

In  view  of  the  results  obtained,  certain  legislation  was  suggested 
for  Great  Britain  to  the  effect  that  either  textiles  used  for  articles 
of  dress,  or  ready  made  clothing  composed  of  such  materials,  be 
labelled  "burns  rapidly"  unless  passing  the  above  test,  or  "non- 
flaming"  if  passing  the  test. 

Not  only  are  the  most  delicate  fabrics  wholly  unharmed  by  the 
"  non-flame  "  treatment,  but  tests  (see  Appendix,  "Red  Book" 
No.  148)  go  to  show  that  the  strength  of  treated  materials,  and 
hence  the  wearing  capacity,  are  increased  by  some  19  per  cent. 


CHAPTER  XXXIII. 
WATCHMEN,   WATCH-CLOCKS   AND   MANUALS. 

THE  various  means  in  ordinary  use  for  the  protection  of  prem- 
ises against  fire  and  for  the  notification  of  the  fire  department — 
all  involving  the  human  element  —  include: 

Watchman, 

Watchman  and  portable  watch-clock, 

Watchman  and  stationary  watch-clock, 

Watchman  and  central  station  supervision, 

Auxiliary  boxes,  and 

Manual  fire  alarm  system. 

Watchmen.  —  The  question  of  watchman  service,  whether  or 
not  accompanied  by  watch-clock  or  central  station  supervision, 
is  one  of  many  pros  and  cons. 

On  the  one  hand,  there  are  those  who,  perhaps  unduly,  em- 
phasize the  faults  of  watchmen  —  faults  not  only  of  omission, 
but  of  commission.  Not  only  must  it  be  frankly  admitted  that 
the  average  watchman,  through  sleeping,  neglecting  his  duties, 
or  even  spending  portions  of  his  time  away  from  the  premises  he 
is  supposed  to  guard,  often  fails  to  discover  a  fire  which  he  might 
reasonably  be  expected  to  discover,  but  it  is  equally  true  that 
watchmen  have  actually  caused  many  fires,  through  the  careless 
use  of  matches,  by  smoking,  or  by  opening  or  dropping  lanterns. 
A  recent  fire  in  Boston  involving  a  loss  of  about  a  million  dollars 
is  attributed  to  a  watchman's  carelessness. 

Again,  a  watchman  is  very  liable  to  do  the  wrong  thing  at  the 
critical  time,  either  from  excitement  or  lack  of  intelligence.  He 
often  undertakes  to  control  a  fire  which  has  secured  considerable 
headway  (as  in  the  case  of  the  Equitable  Building  fire),  when  his 
first  duty  should  be  the  sounding  of  an  alarm;  or  he  may  become 
panic  stricken  after  trying  to  extinguish  a  fire,  and  completely 
overlook  the  presence  of  a  fire  alarm  box  (as  was  the  case  in  the 
Boston  fire  above  mentioned).  Conversely,  a  watchman  could 
often  control  an  incipient  fire,  did  he  not  leave  the  spot  to  turn 
in  the  alarm  first. 

944 


WATCHMEN,  WATCH-CLOCKS   AND    MANUALS        945 

Such  uncertainties  in  the  human  factor  must  always  be  reck- 
oned with  in  the  matter  of  watchman  service,  but,  on  the  other 
hand,  there  is  no  question  that  watchmen  are  often  efficient,  and 
their  employment  is  not  likely  to  be  wholly  discontinued  in  favor 
of  any  purely  automatic  device  which  has  so  far  been  evolved. 
Watchmen  are  usually  employed  quite  as  much  to  guard  against 
burglary  as  to  prevent  the  breaking  out  or  spread  of  fire;  and, 
whatever  their  merits  or  demerits,  they  are  undoubtedly  here 
to  stay  until  some  better  form  of  guarding  property  is  devised. 
The  great  need,  therefore,  is  increased  vigilance,  efficiency,  and 
intelligence  on  the  part  of  watchmen.  These  factors  depend 
upon  the  man,  the  system  under  which  he  is  supervised,  the 
general  condition  of  the  plant  or  building  where  he  is  employed, 
and  the  care  or  indifference  of  those  responsible  for  his  service. 

The  Man.  —  The  average  employer  seldom  realizes  the  full 
responsibility  and  the  trying  conditions  imposed  on  a  watchman. 
For  at  least  a  half  of  each  day  the  entire  property  is  entrusted 
to  his  care.  To  fulfil  this  duty  properly  requires  an  able-bodied, 
intelligent  and  conscientious  man,  and  not  some  aged  or  crippled 
pensioner,  however  worthy  of  charity  such  individuals  may  be. 

I  think  anyone  who  has  made  extensive  examinations  of 
properties  will  agree  that  the  owner  of  a  million  dollar  plant  is 
apt  to  go  off  on  his  yacht  to  Europe  or  elsewhere,  and  leave  his 
property  in  the  hands  of  a  man  who  can  hardly  read  or  write,  or 
perhaps  a  man  who  has  been  injured  in  his  factory,  and  who  will 
hardly  know  what  to  do  in  case  of  a  fire -or  an  accident.* 

The  employment  of  any  watchman  with  physical  disability 
or  mediocre  intelligence  to  supervise  the  maintenance  and  opera- 
tion of  fire  protection  measures  is  plainly  a  failure  to  realize  the 
great  importance  of  fire  protection  itself. 

The  National  Fire  Protection  Association  has  suggested  that  a 
watchman  be  capable  of  fulfilling  the  following  requirements: 

First:  Should  be  thoroughly  reliable  and  trustworthy,  able- 
bodied,  preferably  young  —  say  between  21  and  50  —  eyesight, 
hearing  and  sense  of  smell  unimpaired,  and  above  all  things  must 
not  be  a  smoker. 

Second:   Be  able  to  speak  fluently  the  English  language. 

Third:  Should  have  sufficient  mechanical  knowledge  and  be 
perfectly  drilled  in  the  use  of  the  ordinary  fire  appliances,  and, 
in  other  sprinklered  and  other  highly  improved  risks,  should  be 

*  S.  R.  Walbridge  at  Eleventh  Annual  Meeting  of  The  National  Fire  Pro- 
tection Association. 


946         FIRE   PREVENTION   AND   FIRE    PROTECTION 

able  to  fire  boilers,  start  fire  pumps,  and  be  familiar  with  control- 
ling valves  in  the  sprinkler  equipment.* 

Fire  Protection  and  Other  Duties.  —  There  is  also  a  tendency  to 
make  fire  protection  vigilance  one  of  several  duties.  Thus,  in 
addition  to  police  service,  watchmen  are  often  required  to  attend 
to  boilers,  clean  up  premises,  watch  drying  processes,  etc.  Such 
added  duties  often  involve  distinct  fire  hazards,  but,  if  not  dan- 
gerous and  if  not  so  numerous  as  to  interfere  with  his  recognized 
cares  as  a  watchman,  they  may  even  be  valuable  in  giving  him 
more  to  occupy  his  time  and  in  making  him  appreciate  his  re- 
sponsibility more  fully. 

Watch  service  at  best  is  lonely,  tedious  and  fatiguing,  and 
whereas  in  military  or  naval  regulations  the  tour  of  duty  is 
limited  to  a  few  hours,  in  business  practice  it  is  the  entire  night 
of  twelve  hours  or  more.  It  is  the  severest  test  of  a  man's  en- 
durance to  exercise  proper  care  and  vigilance  for  so  long  a  period, 
and  this  affords  some  explanation  of  the  many  instances  of  large 
fires  getting  under  headway  without  discovery  by  a  watchman.! 

During  a  discussion  on  watchman  service  before  the  1907 
Annual  meeting  of  the  National  Fire  Protection  Association, 
Mr.  F.  E.  Cabot  of  the  Boston  Board  of  Fire  Underwriters  re- 
ported that,  in  the  first  ten  days  of  central  station  supervision 
over  the  watchman  in  a  certain  risk,  when  the  watchman  would 
naturally  be  supposed  to  be  especially  vigilant,  he  was  found 
asleep  twelve  times;  while  in  another  case,  ten  men  had  to  be 
discharged  before  one  could  be  obtained  to  transmit  a  good 
record  of  rounds  to  the  central  station.  The  state  of  affairs 
which  existed  before  the  central  station  supervision  was  intro- 
duced may  be  imagined. 

Suggested  Requirements  for  Watch  Service.  —  The  fol- 
lowing requirements  as  to  watchman  service  have  been  suggested 
by  the  National  Fire  Protection  Association  :J 

FIRST:  That  a  watchman  should  report  for  duty  about 
one-half  hour  before  those  whose  responsibility  he  assumes  leave 
the  premises. 

SECOND:  That  the  first  inspection  be  begun  immediately 
after  operations  are  suspended,  and  to  be  carefully  and  diligently 
made,  and  to  include  all  parts  of  the  premises. 

*  Proceedings  of  Tenth  Annual  Meeting  of  National  Fire  Protection  Asso- 
ciation. 

t  Insurance  Engineering,  March,  1906. 
J  See  1906  Annual  Proceedings,  page  219, 


WATCHMEN,  WATCH-CLOCKS   AND   MANUALS        947 

THIRD:  That  after  the  first  tour  of  inspection,  one  trip/ 
starting  on  the  beginning  of  each  hour,  be  made  throughout  all 
manufacturing  sections  during  the  entire  night  until  the  arrival 
in  the  morning  of  such  persons  as  shall  relieve  him  of  his  responsi- 
bility. 

FOURTH:  That  after  the  first  trip,  warehouses,  stock 
houses,  and  other  non-manufacturing  locked  buildings  may  be 
visited  at  intervals  of  not  exceeding  two  hours,  and  where  the 
whole  interior  can  be  seen  from  outside  need  not  be  entered. 

FIFTH:  That  during  the  daytime  of  Sundays  and  holidays, 
or  when  the  plant  is  not  in  operation  during  the  day  time,  trips 
may  be  made  at  intervals  of  two  hours. 

SIXTH:  That  the  traversing  of  each  floor  once  each  round 
is  sufficient. 

SEVENTH:  That  so  far  as  possible  the  opening  of  fire  doors 
between  sections  be  avoided,  unless  doors  are  automatic  and  so 
maintained  by  the  watchman  if  opened  by  him. 

EIGHTH:  That  a  watchman  should  have  an  interval  of  rest 
of  from  fifteen  to  twenty  minutes  between  trips. 

NINTH:  That  where  the  premises  to  be  covered  are  of  such 
area  as  to  consume  an  hour  or  more  for  one  trip,  two  watchmen 
should  be  employed,  either  dividing  the  area  or  making  trips 
alternately. 

TENTH:  That  the  first  action  expected  of  a  watchman 
after  discovering  a  fire  is  to  give  an  alarm,  after  which  he  shall  be 
expected  to  use  fire  appliances. 

It  is  assumed  that  such  a  service  as  is  above  outlined  would 
include  the  use  of  a  standard  signaling  system  by  the  watchman. 

Methods  of  Supervision.  —  To  promote  the  efficiency  of 
watchman  service,  systems  of  supervision  have  been  devised 
through  the  use  of  watch-clocks  or  through  connection  to  a 
central  station,  whereby  the  watchman  is  required,  at  certain 
intervals,  to  visit  designated  stations  and  to  there  record  the 
time  of  his  visits.  These  records  may  be  made  on  a  portable 
watch-clock,  on  a  stationary  watch-clock,  or  time  detector,  or  to 
a  central  station. 

Portable  Watch-clocks.  —  A  portable  watch-clock,  carried 
by  the  watchman  on  his  rounds,  is  the  simplest  form  of  a  time 
recorder.  In  size  and  appearance  it  usually  resembles  an  alarm 
clock  within  a  leather  case,  being  carried  by  a  strap  over  the 
shoulder.  The  record  is  made  on  a  paper  dial  within  the  clock, 
by  inserting  a  key,  the  turning  of  which  punctures  or  embosses 
the  dial  with  the  numbers  or  designations  of  the  several  boxes 
located  at  the  places  to  be  visited  on  the  round.  The  revolution 
of  the  dial,  which  is  graduated  to  hours  and  minutes,  is  controlled 
by  the  clock  movement.  The  exact  time  at  which  each  key  is 


948 


FIRE    PREVENTION    AND    FIRE    PROTECTION 


"used  is  thus  recorded,  so  that  the  dial  gives  a  complete  diagram- 
matic record  of  the  watchman's  regularity  or  negligence. 

Clock.  —  An  approved  form  of 
portable  watch-clock,  manufactured 
by  the  Newman  Clock  Company, 
is  shown  in  Fig.  382.  The  clock- 
face  dial  of  silvered  metal,  with 
black  hands,  is  visible  to  the  watch- 
man in  determining  the  time  for 
starting  and  the  time  to  be  con- 
sumed in  making  rounds.  The 
case  is  equipped  with  a  pricking 
device  which  registers  upon  the 
paper  dial  every  opening  and 
closing  of  the  clock  and  the  exact 
time  thereof.  The  face  is  covered 
with  a  grille  guard  to  protect  the 
crystal. 

Stations.  —  At  approved  stations 
throughout  the  premises  to  be 
covered,  —  that  is,  at  stations  lo- 
cated so  that  the  inspection  of  every 
part  of  the  building  or  buildings 
is  included,  as  determined  by  the 
Underwriters'  Inspection  Department  having  jurisdiction,  —  are 
located  "station  boxes"  or  " patrol  boxes,"  as  illustrated 
in  Fig.  383.  These  are  attached  to  walls,  columns,  or  other 
suitable  immovable  supports  by  means  of  sealed  screws,  so  that 
the  removal  of  any  box  would  necessitate  the  breaking  of  two 
seals.  To  prevent  the  keys  from  being  detached  and  carried  to 
some  convenient  place  where  the  watchman  could  operate  them 
without  making  his  rounds,  flexible  but  non-repairable  chains 
are  used  to  secure  the  keys  in  the  boxes. 

For  locations  where  it  is  desirable  to  secure  the  keys  against 
theft,  cast-iron  patrol  boxes  may  be  used  in  which  the  station 
keys  are  locked.  All  such  boxes  may  be  opened  with  one  master 
key. 

The  clocks  are  made  of  6,  9,  12,  16,  24  and  35  stations  capacity. 
Rounds  of  9,  12  or  16  stations  are  most  usual.  For  hourly 
rounds,  24  stations  should  be  a  maximum,  as,  allowing  two  min- 
utes per  station,  these  would  require  48  minutes  to  register. 


FIG.  382.  —  "-Newman"  Portable 
Watchman's  Clock. 


WATCHMEN,  WATCH-CLOCKS   AND   MANUALS        949 


Keys.  —  In  the  type  here 
described,  each  key  has  a 
different  raised  number  or 
character  upon  the  right- 
angle  flange,  which,  when 
the  key  is  inserted  and 
turned  in  the  close  fitting 
key-hole  of  the  clock  presses 
the  paper  dial  against  a 
female  die  or  matrix,  thus 
embossing  the  key  number 
or  character  upon  the  re- 
cording dial.  The  revolu- 
tion of  the  dial  by  the  clock 
movement  shows  the  exact  FIG.  383.  — Patrol  Key  Box. 

time    of    each    impression. 

A  nine-station  dial  is  shown  in  Fig.  384.     This  record  shows  that 
nine  stations  were  regularly  visited  from  6.30  P.M.  to  6.30  A.M., 


FIG.  384.  —  Dial  Record  of  Portable  Watchman's  Clock. 

except  that  two  rounds  at  12.30  and   1.30  respectively  were 
altogether  omitted  by  the  watchman. 

The  advantages  of  a  portable  clock  include  cheapness  and 


950 


FIRE    PREVENTION    AND    FIRE    PROTECTION 


simplicity  of  operation  and  maintenance.  Disadvantages  include 
liability  to  breakage  and  getting  out  of  order.  As  the  cost  of 
even  the  best  clock  is  not  great,  the  possibility  of  a  discontinu- 
ance of  the  service  through  being  out  of  order  is  obviated  by 
always  keeping  a  second  or  reserve  clock  in  hand. 


FIG.   385.  —  "Simplex"  Watchman's  Recorder. 

Stationary  Watch-clocks,  or  Magneto  Recorders.  —  A 

development  of  the  portable  watch-clock  is  the  stationary  mag- 
neto recorder,  which,  in  general  appearance,  resembles  an  ordinary 
office  clock.  This  recorder,  placed  in  the  office  or  at  some  central 
point  of  plant  or  building,  —  preferably  where  not  under  obser- 
vation of  watchman,  so  that,  if  out  of  order,  the  fact  is  not  neces- 
sarily known,  —  is  similar  to  the  portable  watch-clock  in  that 
a  clock  mechanism  and  a  revolving  paper  dial  are  used;  but  the 
dial  record,  instead  of  being  embossed  by  a  key,  is  made  elec- 


WATCHMEN,  WATCH-CLOCKS   AND   MANUALS     '  951 


trically  through  the  action  of  small  magneto  generators,  used  as 
station  or  patrol  boxes,  the  operation  of  which,  by  the  watchman, 
induces  an  electric  current  which  gives  distinctive  records  in  the 
recorder  for  the  various  boxes. 

Recorder.  —  Magneto  recorders  are  usually  made  with  a  cylin- 
drical dial,  which  revolves  on  a  drum  or  cylinder,  or  with  a 
flat,  circular  dial,  exactly  as  used  in  portable  clocks. 

A  ''Simplex"  magneto  recorder  is  illustrated  in  Fig.  385. 
This  contains  any  required  number  of  magnets,  with  a  correspond- 
ing number  of  armature  levers  which  have  prick-pins  hinged 
directly  upon  them  —  one  magnet  and  lever  being  connected 
to  each  station  box.  The  operation  of  a  magneto  station  box 
causes  a  flow  of  electricity  through  the  coil  of  wire  around  the 
recorder  magnet,  the  attraction  of  which  operates  the  lever  bar 
and  forces  the  point  of  the  prick-pin  through  the  paper  record 
sheet,  which  is  wrapped  around  a  grooved  hard-rubber  cylinder 
which  revolves  under  the  clock  movement.  The  lever  then  re- 
turns to  its  inoperative  position  by  gravity. 


FIG.  386. — Typical  Record  Sheet,  Magneto  Watchman  Recorder. 

Dial  Record.  —  In  this  particular  type  of  recorder,  the  paper 
record  sheet  is  rectangular  and  cross-ruled.  The  vertical  lines 
represent  30-minute  divisions  of  time.  The  record  for  each 
station  then  appears  as  a  horizontal  line  of  perforations.  A 
separate  space  at  the  top  of  the  record  sheet  also  shows  the  exact 


952 


FIRE   PREVENTION   AND   FIRE   PROTECTION 


time  at  which  the  door  of  the  recorder  is  opened  or  closed.  It 
is  thus  impossible  for  the  watchman  or  any  other  person  to  open 
the  case  and  tamper  with  the  record. 

A  portion  of  a  typical  record  sheet  is  illustrated  in  Fig.  386. 
This  covers  a  15-station  route  every  hour  from  6  P.M.  to  5.30 
A.M.,  with  an  hour's  rest  after  the  midnight  round.  The  record 
shows  that  the  watchman  failed  to  register  from  box  No.  7  on  his 
12  o'clock  trip.  The  door  record  also  shows  that  the  recorder 
was  opened  to  put  on  or  to  remove  the  record  sheet  at  7.30  A.M. 
and  at  8.10  A.M.,  and  at  no  other  time. 

Other  types  of  recorders,  such  as  the  Holtzer-Cabot,  the 
Howard,  etc.,  employ  circular  recording  dials. 

Stations.  —  The  station  boxes,  whether  with  wood  cases,  or 
with  pressed-steel  case  as  shown  in  Fig.  387,  each  contain  a  small 


FIG.  387.  —  Pressed  Steel  Station  Box     FIG.    388.  —  Mechanism    of    Magneto 
for  Use  with  Magneto  Recorder.  Generator. 

magneto  generator  of  the  type  commonly  used  in  telephones. 
This  magneto,  shown  in  Fig.  388,  is  an  electro-mechanical  device 
for  producing  an  electric  current.  It  is  operated  by  a  crank  key, 
which  fits  all  stations,  and  which  is  carried  by  the  watchman, 
who  gives  one  or  two  turns,  thus  sending  a  current  through  the 
connecting  wiring  to  the  proper  magnet  in  the  recorder.  Each 
station  box  is  connected  to  the  recorder  by  a  separate  wire,  while 
a  common  return  wire  connects  all  stations. 

Magneto  recorders  are  made  to  accommodate  as  many  as 
fifty  station  boxes,  or  even  sixty,  but  fifteen  or  twenty  stations 
or  less  are  most  commonly  used. 


WATCHMEN,  WATCH-CLOCKS   AND   MANUALS        953 

As  compared  with  portable  watch-clocks,  stationary  watch- 
man's clocks  are  generally  less  liable  to  breakage,  because  sta- 
tionary, —  and  less  liable  to  become  out  of  order,  because  larger 
and  hence  generally  better  made.  Disadvantages  of  stationary 
clocks  include  the  expense  of  installation,  and  the  liability  of 
wiring,  magnetos,  etc.,  to  get  out  of  order. 

Central  Station  Night  Watch  and  Fire  Alarm  System.  — 
A  watchman's  clock,  whether  portable  or  stationary,  will  give 
the  employer  a  morning  record  of  the  faithfulness  or  faithlessness 
of  his  watchman  during  the  preceding  night,  but  in  case  of 
neglect  of  duty,  no  correction  can  be  made  until  the  following 
day  —  then,  perchance,  too  late.  If  the  negligence  of  the  watch- 
man results  in  the  destruction  of  the  plant  by  fire,  the  clock  and 
the  tell-tale  dial  are  also  destroyed. 

To  remedy  this  possibility,  and  also  to  exercise  immediate 
supervision  over  the  watchman  at  all  hours,  the  central  station 
system  was  devised.  This  service  is  conducted  by  means  of 
electrical  apparatus  which  receives  and  records  signals  which  are 
transmitted  from  the  watchmen  in  risks  so  equipped. 

Location  of  Watch  Boxes.  —  Watch  boxes  must  be  located  as 
required  by  the  Inspection  Department  having  jurisdiction.  In 
general,  the  locations  should  be  such  that  the  watchman,  on  his 
rounds,  will  cover  the  entire  building  or  plant.  Not  more  than 
200  feet  should  have  to  be  traversed  in  order  to  reach  a  box. 

^  Where  buildings  are  more  than  one  story  in  height,  boxes 
must  be  located  on  the  first  story,  and  at  least  one  in  alternate 
stories:  i.e.,  3rd,  5th,  7th,  etc.  Where  buildings  have  a  single 
floor  area  of  7500  square  feet  or  over,  there  shall  be  at  least  one 
box  on  each  floor. 

Where  any  plant  or  building  is  divided  into  sections,  boxes 
must  be  located  in  each  section  to  agree  with  the  above,  no  ac- 
count to  be  taken  of  boxes  in  any  other  section.* 

Not  more  than  forty  boxes  may  be  connected,  nor  more  than 
five  watchmen  may  report  on  any  one  circuit. 

Type  of  Watch  Boxes.  —  Watch  boxes  must  be  of  an  approved 
pattern,  and  be  so  arranged  that  watch  signals  —  or  the  usual 
O.K.  signals  of  the  watchman's  rounds  —  shall  be  distinct  from 
fire  signals.  The  system  must  be  so  arranged  that  the  inter- 
ference of  watch  and  fire  signals  will  be  impossible  under  any 
conditions  likely  to  be  met  with  in  practice,  and  also  so  arranged 

*  Rules  and  Requirements  of  National  Board  of  Fire  Underwriters. 


954         FIRE   PREVENTION   AND   FIRE   PROTECTION 

as  to  register  distinctive  " trouble"  signals  when  any  part  of  the 
system  is  grounded,  broken,  or  so  impaired  as  to  prevent  the 
transmission  of  fire  signals. 

Central  station  supervision  provides  two  very  important  factors 
of  service,  viz.,  watch  service  and  fire  alarm  service. 

Watch  Service  comprises  the  central  station  supervision  of  the 
watchman.  This  insures  constant  vigilance  on  the  part  of  the 
watchman  or  watchmen  employed,  and  provides  for  a  substitute 
in  case  a  watchman  is  at  any  time  temporarily  incapacitated. 

Vigilance  is  enforced  by  means  of  the  perfect  check  which  is 
kept  on  the  watchman's  rounds,  as  reported  from  the  watch 
boxes,  which  electrically  register  at  the  central  station  when 
operated  by  the  watchman.  The  time  of  each  signal  on  the 
rounds  is  accurately  noted,  and  any  serious  irregularity  on  the 
part  of  the  watchman  is  at  once  investigated  by  a  " runner" 
despatched  from  the  central  office.  In  some  cases  the  employer 
is  also  notified  as  soon  as  any  delinquency  occurs,  but  in  all  cases 
the  employer  receives  each  morning  a  written  record  of  his  watch- 
man's attention  to  duty  during  the  preceding  night. 

To  send  a  watch  signal  it  is  necessary  for  the  watchman  simply 
to  insert  a  key  in  the  watch  box,  turning  it  to  the  left,  but  with- 
out opening  the  door.  A  short  signal  giving  one  round  of  the 
box  number  is  thereby  transmitted  to  the  central  station,  where 
it  is  automatically  recorded  by  an  ink  register.  The  signal 
checker  then  immediately  enters  a  record  of  the  signal  on  the 
tally  sheet  in  a  space  corresponding  to  the  location  of  the  signal 
box,  and  the  time  at  which  the  signal  is  due.  These  tally  sheets 
are  provided  for  each  subscriber,  and  are  arranged  to  show  in 
vertical  and  horizontal  columns  the  locations  of  the  watch  boxes 
and  the  time  at  which  signals  are  received  from  each  box,  also 
the  routine,  whether  hourly  or  otherwise,  which  each  watchman 
is  expected  to  follow,  and  the  number  of  minutes  grace  to  be 
allowed  the  watchman  before  a  runner  is  sent  to  investigate. 

Fire  Alarm  Service.  —  A  second  service  of  great  value  per- 
formed by  central  station  supervision  is  that  of  fire  alarm  trans- 
mission, whereby  either  the  watchman  at  night,  or  other  persons 
during  the  day,  may  at  once  transmit  alarms  of  fire  to  the  central 
station  for  re-transmission  to  the  fire  department  headquarters, 
without  the  delay  of  going  to  a  street  alarm  box. 

To  send  in  an  alarm  of  fire,  the  ordinary  method  is  to  break  in 
a  small  square  of  glass  in  the  box  cover,  thereby  releasing  the 


WATCHMEN,  WATCH-CLOCKS  AND    MANUALS        955 

door  and  displaying  the  instructions  "For  Fire,  Pull  the  Lever 
all  the  Way  Down."  By  pulling  the  lever  down  once  and  re- 
leasing it,  a  fire  signal  is  repeated  seven  times  at  the  central  office 
register.  As  the  time  required  to  complete  the  full  fire  signal  is 
fifteen  or  twenty  times  as  long  as  that  required  for  a  watch  signal, 
there  is  little  probability  of  a  series  of  separate  watch  signals 
interfering  with  all  rounds  of  a  fire  alarm  call.  A  single  round 
of  the  fire  signal,  taking  usually  about  six  seconds  for  completion, 
is  sufficient  to  indicate  with  accuracy  the  location  of  the  fire. 
The  fire  signal,  which  is  automatically  recorded  at  the  central 
station,  is  distinguished  from  the  ordinary  watch  signal  by  being 
preceded  on  each  of  the  seven  rounds  by  the  Morse  symbol  F 
(--  --),  signifying  fire.  The  box  mechanism  should  contain  a 
device  to  prevent  more  than  one  box  in  any  building  from  send- 
ing in  an  alarm  of  fire  at  one  and  the  same  time,  thus  providing 
against  the  interference  of  signals. 

Upon  receiving  a  fire  alarm  at  the  central  station,  —  the  noti- 
fication being  both  by  sound  and  as  recorded  on  the  tape,  —  the 
building  number  is  at  once  re-transmitted  to  the  fire  department 
and  to  the  insurance  patrol,  where  the  number  is  received  on 
special  " tappers/'  thus  indicating  to  the  department  and  insur- 
ance patrol  the  exact  building  from  which  the  alarm  was  turned 
in.  The  floor  number  is  not  transmitted,  on  the  assumption 
that  the  watchman  will  notify  the  department,  upon  its  arrival, 
as  to  the  exact  location  of  the  fire. 

Manual  Fire  Alarm  Systems.  —  Wherever  a  public  fire 
alarm  system  exists,  a  manual  system  may  be  installed.  This 
consists  of  any  number  of  stations  or  boxes  within  a  building, 
from  which  an  alarm  of  fire  may  be  sent  to  fire  department 
headquarters.* 

"Special  Building  Signals."  —  As  first  installed  in  New  York 
City,  manual  fire  alarm  systems  were  known  as  "  special  building 
signals"  for  the  reason  that  the  service  consisted  of  special  wires, 
running  direct  from  each  building  so  equipped  to  fire  department 
headquarters,  where  the  alarms  .consisted  of  special  numbers 
designating  individual  buildings,  thus  giving  rise  to  the  term 
" special  building  signal." 

Auxiliary  Boxes.  —  Partly  through  competition  on  the  part 

*  Connections  to  individual  engine  houses,  etc.,  are  not  approved,  for  the 
reason  that  the  company  may  be  absent  on  another  call  when  an  alarm  is 
received. 


956         FIRE    PREVENTION    AND    FIRE    PROTECTION 

of  fire  alarm  companies,  and  partly  through  the  great  increase 
in  the  number  of  special  wires  and  signals  required  to  serve  many 
buildings,  permission  was  given  the  fire  alarm  companies  operat- 
ing in  New  York  City  to  connect  manual  boxes  in  buildings  to 
the  nearest  street  fire  alarm  box.  In  this  system  the  mechanism 
of  the  nearest  public  street  box  was  "  auxiliarized "  by  means  of 
electro-mechanical  pull  boxes  or  manuals,  so  that  the  street  box 
was  operated  simultaneously  with  the  pulling  down  of  the  ring 
in  any  of  the  building  auxiliary  boxes  connected  therewith. 
This  attachment  of  auxiliary  circuits  to  street  boxes  in  no  wise 
impaired  or  prevented  the  operation  of  the  latter  from  the  street 
in  the  usual  manner,  but  the  practice  of  permitting  auxiliary 
boxes  has  been  open  to  the  objection  that  the  system  was  under 
no  continuous  responsible  care,  and  also  •  that  only  one  alarm 
could  be  sent  in  from  any  one  circuit  until  restored. 

In  1902  the  Fire  Commissioner  of  New  York  City  refused  to 
allow  any  more  special  building  connections  with  city  fire  alarm 
boxes,  and,  for  the  moment,  it  looked  as  if  no  more  auxiliary 
alarms  could  be  introduced  except  upon  entirely  independent 
wires.  Then  the  New  York  Board  decided  to  approve  manual 
alarms  connected  with  wires  of  automatic  systems  and,  as  a 
result,  the  approval  of  the  Board  having  been  given,  this  Ex- 
change was  called  upon  to  make  allowances  for  such  manuals, 
which  was  done.  Thus,  from  allowing  for  a  special  building 
signal  transmitted  over  separate  and  independent  wires  direct 
to  fire  department  headquarters,  we  finally  came  to  allowing  for 
manual  boxes  transmitting  signals  over  wires  used  also  for  auto- 
matic (thermostat)  alarms,  and  connecting  not  with  fire  depart- 
ment headquarters,  but  with  the  central  office  of  the  automatic 
alarm  company,  whence  the  alarm  is  sent  to  headquarters.* 

• 

In  1904  the  fire  alarm  companies  operating  in  New  York  were 
again  given  permission  to  auxiliarize  street  boxes,  but,  owing  to 
the  previously  stated  objections  to  this  practice,  auxiliary  boxes 
are  not  now  approved  by  Underwriters. 

Manual  Boxes.  —  The  new  Rules  and  Requirements  of  the 
National  Board  of  Fire  Underwriters  concerning  "Signaling  Sys- 
tems" require  that  manual  boxes  be  operated  through  central 
stations  only.  This  is  in  order  that  such  manual  systems  may 
always  be  under  continuous  responsible  care,  so  that  trouble 
signals,  as  well  as  fire  alarm  signals,  may  be  detected  at  once. 
Hence  manual  boxes,  to  be  approved,  must  be  installed  in  con- 
nection with  automatic  fire  alarm  (or  thermostatic)  service,  or 
*  Circular  of  New  York  Fire  Insurance  Exchange,  date  June  28,  1907. 


WATCHMEN,  WATCH-CLOCKS   AND    MANUALS        957 

in  connection  with  automatic  sprinkler  supervisory  service,  both 
registering  at  central  station  as  described  in  Chapter  XXXI, — 
in  connection  with  watchman  central  station  supervision  (or 
without  the  presence  of  watchman,  if  desired)  as  previously 
described  in  this  chapter,  —  or,  where  no  central  station  com- 
pany exists,  by  means  of  special  independent  wires  to  the  public 
[ire  alarm  headquarters.  The  locations  of  such  manual  boxes 
must  conform  to  the  requirements  previously  given  in  this  chap- 
ter for  watch  boxes  with  central  station  connection. 

Where  watchman  service  is  used,  the  central  station  transmits 
to  the  fire  department  a  special  number  indicating  the  building 
only.  Where  watchman  service  is  not  in  force,  as  is  frequently 
the  case  in  connection  with  automatic  fire  alarm  service  and 
sprinkler  supervisory  service,  the  building  number  is  followed  by 
a  second  floor  or  section  number. 

Combination  Drill  and  Auxiliary  Boxes.  —  The  combina- 
tion drill  and  auxiliary  fire  alarm  boxes  used  in  the  Boston  public 
school  buildings  have  previously  been  described  in  Chapter 
XXIII  (see  page  752).  Similar  boxes  are -made  by  the  Game- 
well  Fire  Alarm  Telegraph  Co.  Such  a  system  is  invaluable 
in  public  institution  buildings,  factories,  etc.,  especially  where 
large  numbers  of  people  are  housed,  thus  making  the  saving  of 
lives  of  paramount  importance. 

Allowances,  covering  watchmen,  watch-clocks  and  manual 
alarms,  as  used  by  the  Boston  Board  of  Fire  Underwriters  and  by 
the  New  York  Fire  Insurance  Exchange,  are  as  follows: 


Boston  Board 
of  Fire  Un- 
derwriters. 

N.Y.  Fire  Insur- 
ance Exchange. 

Watchman  and  approved  watch- 
clock 

7J  per  cent. 

2J  per  cent,  not 
exceeding  025 

Watchman,  watch-clock  and 
manuals  .  . 

10  percent. 

7^  per  cent,  not 
exceeding  .075 

Watchman  with  central  station 
supervision  and  manuals  

12|  per  cent. 

1\  per  cent,  not 
exceeding  .075 

Watchman  and  automatic  fire 
alarm  

12^percent. 

12£  per  cent,  not 
exceeding  .125 

Watchman,  central  station  su-  ) 
pervision,  and  automatic  fire  > 
alarm  •  ) 

15  percent. 

17^  per  cent,  not 
exceeding  .175 

Special  building  signal  (manual) 

C2i\  per  cent 

958         FIRE   PREVENTION   AND   FIRE    PROTECTION 

Limited  Watch.  —  There  are  some  risks,  as  for  instance  storage 
stores,  where  it  is  undesirable,  or  impossible,  for  watchmen  to  go 
through  the  buildings.  Such  omissions  of  watch  service  must 
only  be  by  agreement  with  the  Underwriters,  but  for  such  cases 
the  Boston  Board  usually  makes  allowances  as  follows: 

Watchman  and  Watch-clock 5  per  cent. 

Watchman  with  Central  Station  Supervision 1\  "      " 

Watchman  and  Manual  Alarm 7J  "      " 

In  buildings  occupied  by  retail  stores  on  ground  floor,  or  ground 
floor  and  basement,  —  where  it  would  be  impossible  or  unde- 
sirable to  employ  watchmen,  —  and  by  offices,  etc.,  on  upper 
floors,  an  allowance  of  7f  per  cent,  is  made  by  the  Boston  Board 
for  watchman  service  on  the  upper  floors,  provided  automatic 
fire  alarm  service  is  maintained  in  the  store  premises. 

Note.  —  In  the  above  allowances,  watchman  service  must 
guarantee  night,  Sunday  and  holiday  watching. 


CHAPTER  XXXIV. 
STANDPIPES,  HOSE  RACKS  AND  ROOF  NOZZLES. 

Essentials  for  Efficient  Standpipe  Service.  —  The  possible 
great  value  of  adequate  standpipe  installation  and  maintenance, 
especially  in  buildings  of  considerable  height,  is  seldom  fully 
appreciated  by  architect  or  owner.  The  provision  of  such  pro- 
tection is  too  often  perfunctory  to  cover  some  requirement  in  the 
local  building  laws  or  some  regulations  of  the  fire  department, 
rather  than  to  provide  and  maintain  suitably  a  fire  protection 
auxiliary  which  is  very  likely  to  prove  of  the  utmost  importance. 
A  proper  and  efficient  standpipe  equipment  must  satisfactorily 
cover  many  details,  which  should  not  be  relegated  to  any  plumber 
in  a  haphazard  fashion,  but  should  be  most  carefully  considered. 
Such  details  include  location,  capacity,  water  supply,  valves  and 
street  connections,  character  of  hose  racks  and  hose,  roof  nozzles 
for  particular  use  under  conflagration  conditions  or  during  fire 
in  adjacent  premises,  and,  last  but  not  least,  some  system  of 
adequate  inspection  and  maintenance.  These  factors  will  be 
briefly  discussed. 

Location.  —  Stand  pipes  should  be  located  in,  or  adjacent  to, 
stairway  shafts,  so  that  they  may  be  readily  found  and  used  by 
either  tenants  or  firemen,  and,  beyond  all  other  considerations, 
the}'  should  be  located  within  some  chase  or  flue  which  will 
amply  protect  them  against  possible  injury  by  fire  or  falling 
debris.  Because  a  standpipe  is  made  of  heavy  iron  piping  filled 
with  water  is  no  reason  why  it  may  not  be  seriously  damaged  or 
rendered  inoperative  by  fire.  Experience  has  shown  the  dis- 
astrous results  which  may  follow  the  placing  of  standpipes  within 
vertical  shafts  which  also  contain  electric  wires,*  while  the  danger 
of  relying  for  protection  or  insulation  upon  the  usual  column 
covering  construction  was  illustrated  by  an  experience  of  the 
New  York  Fire  Department  in  attempting  to  use  a  standpipe 
hose  connection  on  a  floor  immediately  above  a  moderate  fire. 

*  See  Insurance  Engineering,  April,  1905,  page  336. 

959 


960         FIRE    PREVENTION    AND    FIRE    PROTECTION 

In  this  case,  steam,  generated  by  fire  around  the  exposed  pipe 
below,  painfully  injured  several  firemen. 

Obviously,  standpipes  should  be  located  where  there  would  be 
no  danger  of  freezing,  but  they  should  not  be  placed  within  the 
ordinary,  easily  damaged,  plaster  or  tile  column  covering.  They 
should  preferably  be  placed  either  within  stable  and  fire-resisting 
chases  or  shafts  (such  as  wall-slots  in  the  brick  walls  of  stair- 
way enclosures),  or  within  plumbing-  or  vent-shafts  containing 
no  electric  wires  or  other  elements  of  fire  hazard. 

Standpipes  should  preferably  rest  on  a  masonry  foundation, 
but  if  this  is  not  available,  support  may  be  secured  by  means  of 
heavy  iron  hangers,  attached  to  the  floor  beams  or  girders. 

The  arrangement  of  lines  should  be  as  straight  and  direct  as 
possible,  with  no  bends  of  a  radius  less  than  five  times  the  diam- 
eter of  the  pipe. 

The  building  laws  of  some  cities  have  required  exterior  stand- 
pipes  and  ladders  combined,  with  iron  balconies  and  hose  valves 
at  each  floor  level.*  Any  such  equipment  is  decidedly  inferior 
to  an  interior  water-filled  standpipe.  In  the  first  place,  the  hose 
connections  in  such  exterior  installations  will  usually  be  found 
tight  and  rusted  from  exposure  to  the  weather,  as  may  easily  be 
proved  by  attempting  to  operate  any  number  of  the  hose  valves 
attached  to  the  many  exterior  standpipes  placed  on  buildings 
erected  in  New  York  City  during  the  70's  and  SO's.  Again,  the 
use  of  such  exterior  equipments  requires  the  carrying  of  hose 
up  to  the  balcony  levels  —  an  operation  which  will  usually 
consume  quite  as  much  time  and  effort  as  taking  lines  up  stair- 
ways. 

Capacity.  —  In  buildings  of  moderate  height,  6-inch  diam- 
eter standpipes  should  be  installed,  while  in  buildings  over  150 
feet  high,  8-inch  diameter  should  be  a  minimum.  These  sizes 
are  larger  than  are  now  required  by  the  New  York  Bureau  of 
Violations  and  Auxiliary  Appliances  (see  page  968),  but  the 
insufficiency  of  most  present  installations  under  actual  test 
conditions  was  plainly  demonstrated  in  the  Equitable  Building 
fire.  See  later  paragraph  •"Use  of  Standpipes  in  Equitable 
Building  Fire." 

The  strength  of  all  pipe,  valves,  fittings  and  castings  should 
be  carefully  specified,  and  care  be  taken  to  see  by  actual  test 
that  such  requirements  are  enforced.     For  all  ordinary  cases  a 
*  See,  for  example,  the  Chicago  Building  Code,  revised  to  1906. 


STANDPIPES,   HOSE   RACKS   AND    ROOF   NOZZLES     961 

safe  working  pressure  of  300  Ibs.  per  sq.  in.,  or  an  ultimate  or 
bursting  pressure  of  900  Ibs.  per  sq.  in.,  will  be  sufficient. 

Water  Supply.  —  The  success  of  any  standpipe  system  will 
naturally  depend  chiefly  upon  a  sufficient  water  supply  under 
adequate  pressure. 

Sources  of  water  may  be  classified  as  follows: 

(a)  Domestic  City  Water  Supply  (low  pressure),  connected  to 
standpipe  system,  usually  of  insufficient  pressure  to  be  of  service 
except  in  buildings  of  very  moderate  height. 

(b)  Gravity  or  Pressure  Tanks,  connected  to  standpipe  system. 

Sources  (a)  or  (b)  should  be  made  sufficient  for  the  use  of  occu- 
pants of  the  building  before  the  arrival  of  the  fire  department. 
The  regulations  of  the  New  York  Bureau  of  Violations  and  Aux- 
iliary Fire  Appliances  require  as  follows: 

In  all  buildings  over  150  feet  in  height  and  in  such  buildings 
as  come  within  these  regulations  as  to  height  or  area,  such  as 
hotels,  hospitals,  asylums,  theatres  or  other  large  public  struc- 
tures, the  standpipe  line  must  have  approved  tank  or  pump 
supply,  or  both. 

Tanks.  —  Bottom  of  gravity  tanks  must  be  elevated  at  least 
20  feet  above  highest  hose  outlet,  provided  with  separate  feed 
supply,  and  such  tanks  shall  be  of  not  less  than  3500  gallons' 
capacity.  If  used  for  domestic  purposes,  feed  lines  must  be 
properly  arranged  to  insure  constant  supply. 

Pressure  tank  supply  system  or  direct  supply  from  street 
mains  will  be  permitted  in  some  cases,  if  circumstances  warrant 
and  pressures  are  adequate. 

(c)  Local  or  Private  Fire  Pumps.  —  If  gravity  tanks  are  not 
installed,  or  even  where  gravity  tanks  are  employed  in  very 
high  or  very  important  buildings,  some  approved  form  of  fire 
pump  should  be  included  in  the  standpipe  system.     It  is  ex- 
tremely doubtful  as  to  how  many  high  buildings  exist,  without 
fire  pumps  (where  high  pressure  service  is  not  used),  in  which 
sufficient  water  pressure  would  be  available  to  supply  requisite 
nozzle  pressure  on  even  a  few  of  the  upper  stories  during  a  severe 
test.     Efficient  service  necessitates  a  separate  fire  pump  for  such 
emergencies,  but  the  usual  owner  considers  such  a  pump  a  dis- 
proportionately burdensome  safeguard;   so,  unless  such  separate 
fire  pump  is  required  by  law,  the  house  water-supply  pump  is 
usually  relied  upon  to  do  doubtful  duty  as  a  fire  pump  as  well, 
and  if  the  test  is  a  severe  one,  the  supply  of  water  is  generally 
insufficient,  either  while  the  fire  department  is  responding  to  the 
alarm  and  getting  to  work,  or  in  time  of  wide-spread  conflagration. 


962         FIRE   PREVENTION   AND   FIRE   PROTECTION 

To  prove  wholly  efficient  as  to  fire  protection,  each  building 
should  be,  as  far  as  possible,  a  well  protected  unit.  This  is  the 
only  safe  rule  to  follow  when  conflagration  conditions  are  con- 
sidered, as  then  gravity  tanks  are  soon  exhausted,  and  the  public 
department  may  not  be  able  to  render  the  aid  usually  expected. 

Fire  pumps  in  New  York  City,  in  buildings  over  150  feet  high, 
must  be  of  a  capacity  of  at  least  250  gallons  per  minute.  The 
requirements  as  to  the  placing  of  pumps  and  the  protection  of 
boilers  so  as  to  make  them  operative  even  when  surrounded  by 
two  feet  of  water  from  the  discharge  of  fire  hose  above,  as  stipu- 
lated in  Section  102  of  the  Building  Code  (as  quoted  hereafter), 
are  most  important. 

(d)  Fire  Engine  Supply,  after  arrival  of  department,  through 
sidewalk  connections  which  should  be  placed  on  street  fronts  of 
buildings,  in  accessible  locations.     Each  standpipe  should  have 
such  an  outside  two-way  3-inch  standard  connection,  of  thread 
agreeing  exactly  with  the  city  department,   to  be  fitted  with 
proper  caps  and  clapper-valves.     A  metal  sign  attached  to  or 
near  the  connection  and  reading  "  STAND  PIPE  CONNECTION"  is 
valuable  as  distinguishing  the  standpipe  service  from  possible 
automatic  or  open  sprinkler  supplies. 

(e)  High  Pressure  Water  Supply,  or  a  water  system  giving  a 
sufficient  pressure  for  all  fire  streams  when  directly  connected 
to  hydrants  or  standpipes,  without  the  intervention  of  steam 
fire  engines.     High  pressure  or  auxiliary  pipe  systems,   where 
high  water  pressure  is  obtained  either  by  means  of  special  auxili- 
ary high-duty  pumping  stations,  or  else  by  means  of  powerful 
fire-boats  attaching  to  the  mains,  have  already  been  installed 
either  throughout  or  in  portions  of  several  of  our  larger  cities, 
among  which  may  be  mentioned  New  York,  Boston,  Detroit, 
Cleveland  and  Buffalo.     For  requirements  pertaining  to  high 
pressure  fire  systems,  see  Ninth  Annual  Proceedings  of  National 
Fire  Protection  Association. 

Whatever  the  source  of  supply,  the  water  should  invariably  stand 
next  to  the  valves  on  each  floor. 

Check- Valves.  —  Each  steamer  connection  to  standpipe 
should  be  provided  with  a  straightway  check-valve,  in  a  hori- 
zontal portion  of  the  piping,  just  inside  the  building;  and  where 
Siamese  connections  are  used,  they  should  be  provided  with 
double-acting  check-valves  in  the  "Y."  Also,  where  a  tank 
supply  is  provided  for  the  standpipe  system,  a  check-valve  must 


STANDPIPES,  HOSE   RACKS   AND   ROOF   NOZZLES      963 

be  placed  facing  away  from  the  tank,  thereby  allowing  water  to 
flow  from  the  tank  into  the  standpipe,  but  preventing  water 
from  the  standpipe  (possibly  under  heavy  pressure  from  fire 
engine  pumping)  from  passing  into  the  tank. 

Hose  Outlets  and  Valves.  —  The  hose-pipe  branches  at  the 
various  floors  should  be  placed  about  5|  feet  above  the  floor  or 
landing  from  which  the  valve  is  to  be  operated.  The  valves 
should  be  single-disk  gate  pattern,  with  extra  strong  seats,  and 
with  disks  sufficiently  heavy  to  withstand  the  working  pressure 
contemplated.  *  They  should  be  absolutely  water-tight,  made  of 
brass  or  other  non-corrosive  metal,  and  of  2J  inch  clear  opening, 
operation  to  be  by  means  of  a  screw  stem  and  circular  handle. 
In  some  instances  of  particularly  careful  installation,  a  i-in.  drain 
pipe,  which  is  provided  with  a  shut-off  cock,  is  specified  to  be 
placed  leading  from  the  bottom  of  the  nipple  or  hose-coupling, 
immediately  outside  the  valve.  This  is  to  drain  thoroughly  any 
water  left  in  the  hose  after  using,  to  some  waste-  or  rainwater- 
pipe.  When  this  is  done,  the  hose  reels  or  racks  should  be  placed 
immediately  over  the  branches. 

Hose  Racks  are  of  various  patterns,  but  generally  arranged  on 
some  principle  which  will  permit  the  easy  " paying  out"  of  the 


FIG.    389.  —  Wall   Hose   Rack,    Hose         FIG.  390.  —  Wall  Hose  Reel,  Hose 
folded    Layer   by   Layer.  folded  Once. 

hose  when  required  for  use.     The  racks  are  supported  either  by 
clamping  to  the  standpipe  when  the  latter  is  completely  exposed, 


964         FIRE   PREVENTION   AND   FIRE   PROTECTION 


FIG.  391.  - 


—  or  by  fastening  to  the  wall  independent  of  the  standpipe,  — 
or  they  are  suspended  from  and  supported  by  the  valve. 

Fig.  389  illustrates  a  wall 
rack  in  which  the  hose  is  folded 
layer  by  layer,  so  that  the 
running  out  of  the  nozzle  will 
result  in  no  kinks.  Fig.  390 
shows  a  reel,  also  supported 
on  the  wall,  in  which  the  hose 
is  folded  once  and  then  wound 
on  the  reel  double,  so  as  to  pay 
out  completely,  clear  of  the 
reel.  Fig.  391  illustrates  the 
"  Howard  Swinging  Hose 
Rack,"  in  which  the  rack  is 
supported  on  the  valve.  The 
rack  arm  is  open  at  the  outer 
end,  and  each  side  of  the  arm 
is  grooved  on  the  inside  to 

-"Howard"  Swinging  Hose  receive  f-in..  diameter  wooden 
pins,  over  which  -the  hose  is 

looped,  fold  by  fold.  When  the  nozzle  is  grasped  and  run  out, 
the  pins  also  run  out  one  by  one  in  the  grooves,  and  drop  to 
the  floor.  Various  finishes  are  supplied  for  nearly  all  makes  of 
racks. 

Automatic  Valves.  —  A  number  of  automatic  hose-reels  or 
devices  of  a  similar  nature  have  been  patented  and  used  to  some 
extent,  whereby  the  hose  connection  to  the  standpipe  is  made 
automatic  in  action,  so  that  the  operator,  in  manipulating  either 
the  reel  or  hose,  has  a  full  water  supply  at  once,  without  the 
necessity  of  unscrewing  the  valve.  One  familiar  type  is  that  in 
which  the  turning  of  the  rack  at  right  angles  to  the  wall  (or  sup- 
porting surface)  operates  the  valve,  so  that  it  is  only  necessary 
to  run  out  the  hose,  turn  the  rack  through  an  angle  of  ninety 
degrees,  and  the  water  supply  is  immediate. 

Such  devices  are  not  generally  approved  on  account  of  the 
automatic  action  being  insufficiently  controlled,  and  on  account 
of  liability  to  leakage.  The  opening  and  closing  of  the  valve 
through  the  action  of  the  rack  makes  it  difficult  and  often  im- 
practicable to  regulate  the  pressure,  as  was  illustrated  in  a  firs 
in  a  New  York  building,  where  the  pressure  from  the  gravity 


STANDPIPES,    HOSE    RACKS   AND    ROOF    NOZZLES     965 

tanks  on  the  roof  provided  such  a  full  and  sudden  water  supply 
in  a  fire  hose  on  the  fifth  floor  that  the  nozzle  was  so  far  from 
control  as  slightly  to  injure  the  acting  chief  of  the  fire  depart- 
ment. Again,  such  automatic  valves  are  very  apt  to  become 
loose  and  to  leak,  with  the  result  that  the  connection  is  so  tight- 
ened up  as  to  become  inoperative  when  needed. 

"Red  Book"   No.   123  of  The  British  Fire  Prevention  Com- 
mittee  describes   a    very   interesting   " adaptor"   or   automatic 
device  which  may  be  attached  to  any  hydrant,   cock  or  tap, 
whereby  the  supply  of  water  may  be  automatic  and  immediate, 
|  much  as  previously  described. 

The  hydrant  adaptors  in  each  case  were  found  to  open  the 
valves  when  the  hose  was  pulled,  irrespective  of  distance,  direc- 
tion, and  run  of  hose;  and  in  the  major  number  of  the  tests  it 
was  found  that  water  could  be  obtained  at  the  branch  more 
rapidly  when  the  valve  was  opened  by  the  adaptor  than  when 
the  ordinary  screw-down  valve  was  opened  after  the  hose  was 
run  out. 

Hose.  —  Two  and  one-half  inch  hose  is  generally  used  by  city 
fire  departments  for  inside  work,  and  this  size  should  therefore 
be  employed  for  standpipe  branches.  Hose  smaller  than  2J  ins. 
diam.  is  often  insufficient,  while  3-in.  hose  is  too  heavy  and 
cumbersome,  requiring  extra  men  to  handle.  Unless  employees 
or  occupants  are  well  drilled  in  the  use  of  hose  lines,  however, 
even  two  and  one-half  inch  hose  may  well  prove  unmanageable 
where  effective  water  pressure  exists.  Thus  Mr.  W.  C.  Robinson, 
in  his  report  on  the  Parker  Building  fire,  recommends  that,  in 
addition  to  linen  hose  and  nozzles  suitable  for  fire  department 
use,  standpipes  in  mercantile  buildings,  etc.,  should  be  equipped 
with  "smaller  linen  hose  and  nozzles,  suitable  and  safe  for  the 
use  of  occupants." 

The  length  of  hose  apportioned  to  each  rack  should  be  suffi- 
cient to  cover  properly  the  entire  floor  area,  or,  in  cases  of  more 
than  one  standpipe,  to  cover  the  full  area  protected  by  the  stand- 
pipe  in  question.  Ordinary  rack  capacities  care  for  50,  100  or 
150  feet  of  hose. 

For  fire  hose  to  hang  up  in  dry,  warm  rooms  or  stairway 
towers  of  textile  mills,  corridors  of  office  buildings,  etc.,  we  recom- 
mend unlined  linen  hose.  Specify  that  it  be  "  guaranteed  con- 
formable to  the  specifications  of  the  Associated  Factory  Mutual 
Fire  Insurance  Companies." 

It  costs  less  than  half  as  much  as  good  cotton  rubber-lined 


966         FIRE   PREVENTION   AND   FIRE   PROTECTION 

hose,  and,  if  not  used,  will  last  two  or  three  times  as  long.  Its 
chief  value  is  for  short  lines  for  brief  use  inside  of  buildings,  and  it 
is  best  on  account  of  its  superior  lightness,  compactness  and  con- 
venience for  use  by  one  man  alone,  and  because  there  is  little  or 
no  chance  of  its  becoming  stuck  together  by  the  ordinary  heat 
of  the  rooms. 

Remember  that  it  is  almost  impossible  to  judge  from  in- 
spection whether  yarn  is  so  spun  and  the  fabric  so  tightly  woven 
that  it  will  instantly  become  water-tight  under  a  pressure  of 
100  pounds  to  the  square  inch,  and  that  durability  depends  largely 
on  the  preliminary  freeing  of  the  flax  stock  from  the  vegetable 
gum  by  alkali  boiling,  and  that  much  hose  offered  by  commercial 
agents  is  apparently  "made  for  insurance  inspectors  to  look  at," 
and  will  not  hold  water  or  stand  high  pressure.  For  these  reasons, 
therefore,  it  is  safest  to  buy  direct  from  a  responsible  manufacturer, 
whose  name  and  brand  is  on  the  hose  and  name  on  the  couplings, 
so  you  can  get  back  at  him  five  years  hence,  if  need  be. 

Linen  hose  is  injured  every  time  it  is  wet,  but  if  kept  in  a 
dry  place  may  continue  a  reliable  safeguard  for  twenty  years  or 
more.  It  is  not  suitable  for  lines  of  more  than  50  or  100  feet  in 
length  because  of  the  loss  of  pressure  due  to  friction  caused  by 
its  roughness;  and  it  is  not  suitable  for  mill  yard  use  because 
holes  quickly  chafe  through  it  under  pulsations  of  pump  or  when 
laid  over  sharp  stones,  cinders,  or  sharp  corners.* 

Play-pipes  should  be  of  brass,  not  less  than  18  ins.  long,  with 
If-in.  nozzles  and  shut-off  cocks. 

Roof  Nozzles.  —  The  value  of  efficient  standpipe  service,  es- 
pecially if  equipped  with  monitor-  or  roof-nozzles,  should  not  be 
overlooked  in  its  bearing  upon  protection  against  exposure  fires 
or  conflagrations.  In  report  No.  XIII  of  the  Insurance  Engi- 
neering Experiment  Station,  Mr.  Edward  Atkinson  stated  as 
follows : 

No  system  of  safeguards  for  the  prevention  of  loss  by  fire 
can  be  considered  in  any  sense  adequate  or  complete  in  which 
large  supplies  of  water  are  not  carried  to  hydrants  upon  roofs  or 
to  hydrants  within  high  buildings,  from  which  vantage  points 
fires  in  lower  buildings  may  be  promptly  flooded.  In  the  recent 
fire  in  Rochester,  N.  Y.,  one  large  building  had  been  furnished 
with  its  own  steam  fire  pumps  and  pipe  service,  with  hydrants 
upon  the  roof,  from  which  effective  streams  were  thrown,  stop- 
ping the  extension  of  the  fire  at  that  point  and  helping  to  protect 
the  building  on  which  they  were.  In  another  building  a  stand- 
pipe  with  hydrants  at  every  floor  served  hose  from  many  win- 
dows, again  checking  the  fire  in  that  direction.  Roof  hydrants 
and  streams  from  upper  windows  stopped  what  threatened  to  be 

*  From  Inspection  Department  of  the  Associated  Factory  Mutual  Fire 
Insurance  Companies. 


STANDPIPES,  HOSE    RACKS   AND    ROOF    NOZZLES      967 

a  conflagration  in  Philadelphia,  and  the  steam  pumps,  pipes, 
hydrants  and  hose  in  the  silk  mills  of  Paterson  stopped  that 
conflagration  at  its  most  dangerous  point,  and  saved  the  silk 
industry  from  destruction. 


Roof  outlets  should  be  either 
outlets  only,  without  hose  (which 
could  not  be  protected  against 
weather  without  some  prohibitive 
form  of  protection),  or  else 
equipped  with  roof  nozzles,  a  com- 
mendable form  of  which  is  illus- 
trated in  Fig.  392.  These  are  of 
brass,  connected  directly  to  the 
standpipe,  and  are  of  " universal" 
operation,  so  that  they  may  be 
turned  in  any  direction,  and,  at 
the  same  time,  be  operated  in  any 
arc  of  a  circle.  A  protecting  tar- 
paulin should  be  placed  over 
each,  and  every  roof  nozzle  should 
be  provided  with  a  screw  valve  so 
located  on  the  standpipe  as  not 
to  allow  water  to  stand  where 
any  possibility  of  freezing  would 
exist. 

For      recommendations      of      the    FIG.  392.  —  "Glazier"  Universal 

National  Fire    Protection   Associa-      Nozzle,  as  Used  for  Roof  Ser- 
tion    as    to    roof    hydrants,     etc., 

in  connection  with  a  high  pressure  fire  system,  see  Insurance 
Engineering,  July,  1905. 


The  Bureau  of  Violations  and  Auxiliary  Fire  Appliances 
of  the  New  York  Fire  Department  was  organized  in  1903  to 
enforce  the  installation  of  such  auxiliary  appliances  as  could  be 
called  for  under  existing  laws,  and,  also,  to  provide  uniformity 
in  the  character  of  such  appliances.  The  work  of  this  Bureau  is 
prosecuted  under  Section  762  of  the  Greater  New  York  Charter, 
which  requires,  in  practically  all  classes  of  buildings  except 
private  dwellings,  "such  means  of  preventing  and  extinguishing 


968         FIRE    PREVENTION    AND    FIRE    PROTECTION 

fires  as  the  fire  commissioner  may  direct;"  and  under  Section  102 
of  the  Building  Code,  which  refers  to  standpipes  as  follows: 

In  every  building  now  erected,  unless  already  provided  with 
a  three  inch  or  larger  vertical  pipe,  which  exceeds  one  hundred 
feet  in  height,  and  in  every  building  hereafter  to  be  erected  exceed- 
ing eighty-five  feet  in  height,  and  when  any  such  building  does 
not  exceed  one  hundred  and  fifty  feet  in  height,  it  shall  be  pro- 
vided with  a  four-inch  standpipe,  running  from  cellar  to  roof, 
with  one  two-way  three-inch  Siamese  connection  to  be  placed 
on  street  above  the  curb  level,  and  with  one  two-and-one-half 
inch  outlet,  with  hose  attached  thereto  on  each  floor,  placed  as 
near  the  stairs  as  practicable;  and  all  buildings  now  erected,  un- 
less already  provided  with  a  three-inch  or  larger  vertical  pipe,  or 
hereafter  to  be  erected  exceeding  one  hundred  and  fifty  feet  in 
height  shall  be  provided  with  an  auxiliary  fire  apparatus  and 
appliances,  consisting  of  water  tank  on  roof,  or  in  cellar,  stand- 
pipes,  hose,  nozzles,  wrenches,  fire  extinguishers,  hooks,  axes 
and  such  other  appliances  as  may  be  required  by  the  Fire  De- 
partment; all  to  be  of  the  best  material  and  of  the  sizes,  patterns 
and  regulation  kinds  used  and  required  by  the  Fire  Department. 
In  every  such  building  a  steam  pump  and  at  least  one  passenger 
elevator  shall  be  kept  in  readiness  for  immediate  use  by  the  Fire 
Department  during  all  hours  of  the  night  and  day,  including 
holidays  and  Sundays.  The  said  pumps,  if  located  in  the  lower 
story,  shall  be  placed  not  less  than  two  feet  above  the  floor  level. 
The  boilers  which  supply  power  to  the  passenger  elevators  and 
pumps,  if  located  in  the  lowest  story,  shall  be  so  surrounded  by 
a  dwarf  brick  wall,  laid  in  cement  mortar  or  other  suitable  per- 
manent waterproof  construction,  as  to  exclude  water  to  the  depth 
of  two  feet  above  the  floor  level  from  flowing  into  the  ash  pits  of 
said  boilers.  When  the  level  of  the  floor  of  the  lowest  story  is 
above  the  level  of  the  sewer  in  the  street,  a  large  cesspool  shall 
be  placed  in  said  floor  and  connected  by  a  four-inch  cast-iron 
drain  pipe  with  the  street  sewer.  Standpipes  shall  not  be  less 
than  six  inches  in  diameter  for  all  buildings  exceeding  one  hun- 
dred and  fifty  feet  in  height.  All  standpipes  shall  extend  to  the 
street  and  there  be  provided  at  or  near  the  sidewalk  level  with 
the  Siamese  connections.  Said  standpipes  shall  also  extend  to 
the  roof.  Valve  outlets  shall  be  provided  on  each  and  every 
story,  including  the  basement  and  cellar  and  on  the  roof.  All 
valves,  hose,  tools  and  other  appliances  provided  for  in  this 
section  shall  be  kept  in  perfect  working  order,  and  once  a  month 
the  person  in  charge  of  said  building  shall  make  a  thorough  in- 
spection of  the  same,  to  see  that  all  valves,  hose  arid  other  ap- 
pliances are  in  perfect  working  order  and  ready  for  immediate 
use  by  the  Fire  Department.  If  any  of  the  said  buildings  extend 
from  street  to  street,  or  form  an  L  shape,  they  shall  be  provided 
with  standpipes  for  each  street  frontage. 

New  York  Standpipe  Regulations.  —  For  the  purpose  of 
securing  uniformity  and  efficiency  in  the  installation  of  stand- 


STANDPIPES,  HOSE   RACKS   AND    ROOF   NOZZLES      969 

pipes,  the  following  regulations  are  issued  and  enforced  by  the 
Bureau : 

Standpipes  will  be  required  in  all  buildings  exceeding  85  feet 
in  height,  also  in  all  open  or  inclosed  structures  covering  large 
areas,  irrespective  of  height. 

Such  buildings  as  come  within  above  classification,  and  which 
do  not  exceed  150  feet  in  height,  in  which  standpipes  (fire  lines) 
now  installed  are  less  than  3  inches  in  diameter,  must  be  provided 
with  lines  4  inches  in  diameter,  and  in  such  buildings  as  exceed 
150  feet  in  height  the  fire  line  must  be  six  inches  in  diameter, 
unless  the  lines  already  installed  are  considered  satisfactory  and 
approved  by  the  Fire  Department. 

These  standpipes  must  be  of  wrought-iron  or  steel  of  suffi- 
cient strength  to  withstand  the  necessary  pressure  (in  no  case 
less  than  300  pounds  to  the  square  inch)  to  force  adequate  streams 
of  water  to  any  of  the  floors  of  the  building,  or  to  the  roof,  and 
must  extend  from  cellar  to  roof  and  be  connected  with  outside 
two-way  3-inch  standard  Fire  Department  connections,  with 
clapper  valves  and  proper  caps,  placed  on  street  front  of  build- 
ings, above  curb  level,  in  a  position  accessible  for  use  of  Fire 
Department.  These  standpipes  must  be  provided  with  proper 
valves  (gate  valves  preferred)  and  2^-inch  outlets  of  the  regular 
Fire  Department  pattern  and  thread  on  each  floor  level,  with 
sufficient  standard  2Hnch  hose  and  nozzles  attached  thereto  to 
properly  cover  entire  floor  area,  arranged  on  proper  and  approved 
racks  or  reels,  with  approved  open  or  controlling  nozzles.  Proper 
check-valves  shall  be  placed  in  top  and  bottom  of  such  lines  as 
are  required  to  use  tank  or  pump  supply,  or  both.  The  hose  out- 
lets and  hose  must  be  located  within  stairway  inclosures,  except 
where  impracticable  to  do  so  for  reasons  satisfactory  to  the 
Department. 

Where  more  than  one  standpipe  is  installed,  cross  connec- 
tions, preferably  in  basement,  of  same  size  as  main  risers,  or 
larger,  must  be  provided. 

Boston  Standpipe  Practice.  —  In  Boston,  where  no  building 
may  be  built  to  a  height  exceeding  125  feet,  no  mention  is  made 
in  the  building  law  of  standpipe  requirements,  except  for  theatres, 
but  the  Boston  Board  of  Fire  Underwriters  allows  a  reduction  in 
premium  for  such  installations,  provided  the  water  is  always 
next  the  valves,  the  allowance  varying  according  to  the  character 
of  the  risk. 

Elevator  Service. — The  provision  in  the  above  quoted  section 
of  the  New  York  Building  Code  as  to  elevator  service  at  all  hours 
of  every  day  and  night  in  buildings  exceeding  150  feet  in  height, 
is  very  important  from  a  fire  protection  viewpoint.  This  regu- 
lation is  for  the  benefit  of  the  firemen,  in  case  of  need;  for,  in 


970         FIRE    PREVENTION    AND    FIRE    PROTECTION 

buildings  of  great  height,  stairways  will  not  suffice  for  the  proper 
working  of  the  department.  The  difficulty  of  ascending  many 
flights  of  stairs,  even  without  the  added  burden  of  hose,  may, 
under  considerations  of  smoke  or  exertion,  seriously  embarrass 
the  prompt  working  of  the  department,  especially  in  the  ability 
of  the  firemen  to  avail  themselves  quickly  of  the  auxiliary  fire- 
fighting  apparatus  belonging  to  the  building.  Hence  sufficient 
power  should  be  ready  at  all  times  for  the  operation  of  at  least 
one  elevator,  in  addition  to  which  some  competent  employee, 
familiar  with  the  elevator  service  and  also  with  all  auxiliary 
apparatus,  should  be  constantly  on  hand  to  aid  and  direct  the 
firemen.  A  decided  improvement  in  the  above  law  would  be 
to  require  such  elevator  to  be  in  a  thoroughly  fire-resisting 
enclosure. 

Standpipe  Equipment  in  Singer  Building,  New  York.  — 
The  inordinately  high  buildings  in  New  York  City,  such  as  the 
Singer  Building  Tower,  the  Metropolitan  Tower,  and  the  Munic- 
ipal and  Woolworth  buildings,  present  unique  problems  of  fire 
protection  engineering.  It  is  evident,  as  has  been  shown  in 
Chapter  XXIX,  that  no  great  reliance  may  be  placed  on  the 
fire  department  at  such  excessive  heights  unless  adequate 
auxiliary  equipment  is  installed.  In  such  cases,  the  principal 
feature  of  equipment  must  consist  of  the  standpipe  system,  in  the 
design  of  which  many  unusual  factors  must  be  taken  into  con- 
sideration. Thus,  while  no  especial  difficulty  is  presented  in 
pumping  water  to  such  a  height,  the  standpipes  must  be  always 
charged,  thereby  making  a  tank  supply  necessary.  This,  how- 
ever, at  such  great  heights,  means  a  gravity  pressure  which 
would  be  entirely  unusable  at  the  hose  connections  of  the  lower 
stories.  This  defect  exists  to  some  extent  in  a  number  of  mod- 
erately high  buildings  in  New  York,  so  that  in  still  higher  build- 
ings some  means  had  to  be  found  whereby  a  controllable  nozzle 
pressure  would  result.  This  is  usually  accomplished  by  dividing 
the  building  into  a  number  of  vertical  sections,  each  of  which  is 
provided  with  an  independent  tank  supply.  The  first  notable 
example  of  such  a  divided  standpipe  installation  was  in  the 
Singer  Building  Tower,  and  as,  in  that  case,  the  best  possible 
solution  of  the  problem  was  very  carefully  considered,  a  brief 
description  of  the  result  should  be  of  interest. 

Independent  tank  supplies  were  as  follows: 

On  the  42nd  floor,  one  3000-gallon  tank,  which  supplies  the 


STANDPIPES,  HOSE    RACKS   AND    ROOF    NOZZLES      971 

40th  to  38th  floors,  inclusive,  by  means  of  a  4-inch  riser  with  3  hose 
connections.  This  riser  is  connected  to  the  6-inch  riser  leading 
downward  from  next  tank  below  (see  Fig.  393). 

On  the  39th  floor,  one  7000-gallon  tank,  which  supplies  the 
37th  to  26th  floors  inclusive  by  means  of  a  6-inch  riser  with  12  hose 
connections.  This  riser  is  connected  to  a  6-inch  riser  leading 
downward  from  next  tank  below. 


.  h 

3000 
Gal. 
T'ank     H 

42nd  Floor 

i  — 

7  Check  \ 

live  Opening 

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I 

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s 

Cfl 

-2 

s 

41st  Floor 

ffi 

..C/J 

g 

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^ 

S 

t 

a 

& 

"HOSC 

"oo 

Reel 

-°3 

40th  Floor  j 

Hose© 

_jr 

Jc 

al.TT 

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nk 

39th  Floor 

Check  Valve 
Opening: 
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N^ 

Do 

ck  \alve  Opening 
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T  House 

Is 

Supply 

5* 

>\  38th  Floor 
\i 

FIG.    393.  —  Arrangement  of  Pressure   Tanks,   Check-valves,   etc.,   in  Singer 
Building  Tower. 


On  the  27th  floor,  one  5000-gallon  tank,  which  supplies  the 
25th  to  13th  floors  inclusive  by  means  of  a  6-inch  riser  with  16 
hose  connections.  This  riser  is  also  connected  to  a  6-inch  riser 
leading  downward  from  the  next  lower  tanks. 

On  the  13th-  mezzanine  floor,  three  2000-gallon  tanks  con- 
nected, whteh  supply  the  12th  to  basement  floors  inclusive  by 
means  of  two  6-inch  risers  with  14  hose  connections  on  each. 

In  addition  to  the  above,  one  4-inch  riser  with  3  hose  connec- 


972         FIRE   PREVENTION   AND   FIRE   PROTECTION 

tions  at  the  ground,  1st  and  2nd  floors,  connects  with  the  lowest 
level  tank  mentioned  above. 

The  system  has  three  sources  of  water  supply,  viz.,  the  tank 
supply,  the  house  pumps  and  fire  engine  connections. 

The  tank  supply  is  taken  from  a  10,000-gallon  suction  tank 
located  in  the  basement.  Two  500-gallon  pumps  supply  the 
.tanks  at  the  42nd  and  39th  floors  through  10-in.  and  8-in.  main, 
and  the  tank  at  27th  floor  through  a  6-inch  main.  The  13th 
floor  tanks  are  also  supplied  through  3-inch  and  4-inch  mains 
by  two  similar  pumps.  All  of  the  pumps  are  also  arranged  so 
that  they  may  pump  into  the  service  risers  direct. 

The  following  check-valves  were  used: 

a.  —  Check- valves  just  beneath  each  tank,  opening  downward. 
These  prevent  engines  or  pumps  from  filling  and  overflowing 
tanks  from  risers. 

b.  —  Check-valves,  opening  upward,  at  the  foot  of  each  riser 
length,  just  before  the  connection  of  upper  riser  to  lower.     These 
allow  engines  and  pumps  to  fill  risers  from  below,  way  to  top  of 
building,  but  do  not  allow  water  to  return.     The  pressure  from 
each  tank  can  therefore  extend  down  only  to  this  check-valve, 
and  not  to  riser  from  tank  below.     This  insures  workable  pres- 
sures at  hose  connections.     These  check-valves,  with  those  just 
beneath  tanks,  give  each  tank  a  double  protection  from  the 
pressure  of  the  tank  above  (see  Fig.  393). 

c.  —  A  check-valve  at  each  Siamese  connection  guards   the 
engines  from  the  pumps,  while  check  valves  near  the  pumps  guard 
the  latter  from  the  engines. 

A  difficulty  which  presented  itself  was  furnishing  enough 
pressure  for  the  hose  connections  on  the  floors  immediately  be- 
low the  tanks.  This  was  overcome  by  having  the  connections 
on  the  floors  immediately  below  each  tank  supplied  by  the  riser 
for  the  next  upper  section.  For  example:  the  tank  on  the  27th 
floor  begins  to  supply  connections  at  the  25th  floor,  while  the 
connections  on  the  26th  and  27th  floors  are  supplied  by  the  riser 
from  the  39th  story  tank. 

Another  difficulty  arose  from  the  necessity  of  using  the  same 
tanks  for  both  house-  and  fire-service.  The  small  area  of  the 
building  did  not  permit  of  separate  tanks,  so  the  latter  had  to 
be  arranged  for  both  supplies,  but  without  affecting  the  fire  sup- 
ply. This  was  done  by  extending  the  house  pipes  up  and  into 
the  tanks  to  specified  levels,  while  the  fire  risers  were  extended 
only  to  the  bottoms  of  the  tanks.  In  this  way  the  fire  risers  can 
draw  all  the  contents  of  the  tanks,  while  the  house  pipes  can  draw 
only  as  much  water  as  is  above  the  tops  of  the  pipes.  This 


STANDPIPES,  HOSE    RACKS   AND   ROOF    NOZZLES      973 

arrangement  assures  a  constant  fire  supply,  regardless  of  that 
used  for  house  purposes.* 

Use  of  Standpipes  in  Equitable  Building  Fire.  —  Owing 
to  narrow  streets,  high  wind,  and  low  temperature,  the  fire  which 
destroyed  the  Equitable  Building,  January  9,  1912,  was  prin- 
cipally fought  by  means  of  streams  from  standpipes  in  neigh- 
boring buildings.  Such  standpipes  were  usually  supplied  by 
a  local  fire  pump  and  by  one  or  more  steamer  hose  lines  attached 
to  the  Siamese  street  connection.  The  standpipes  in  no  less 
than  ten  separate  buildings  were  thus  utilized  by  the  fire  depart- 
ment for  periods  ranging  from  two  hours  to  two  days,  so  that 
this  fire  undoubtedly  constituted  the  most  comprehensive  test 
so  far  given  to  this  feature  of  fire-protection  equipment.  The 
value  of  such  standpipes  was  amply  demonstrated,  but  this  ex- 
perience also  showed  the  insufficiency  of  most  of  the  installations 
utilized.  It  is  interesting  to  note  that  the  only  standpipe  stream 
which  was  classed  as  "good"  was  that  from  the  6-inch  standpipe 
in  the  Singer  Building. 

The  following  conclusions  concerning  standpipe  experience 
in  this  fire  are  given  by  Mr.  F.  J.  T.  Stewart  in  his  report  on  the 
Equitable  Building  fire  to  the  New  York  Board  of  Fire  Under- 
writers : 

Standpipes.  —  The  extent  to  which  the  standpipes  were 
used  in  the  numerous  tall  buildings  facing  the  Equitable  Build- 
ing across  narrow  streets,  shows  a  laudable  realization  on  the 
part  of  the  fire  department  of  the  futility  of  fighting  fires  above 
50  feet  or  the  4th  story  by  hose  streams  directed  from  the  streets, 
especially  during  a  high  wind. 

It  is  apparent  from  personal  observations  and  from  the 
records  that  hardly  a  hose  stream  was  directed  at  the  fire  from 
the  street  level  except  a  number  of  streams  used  chiefly  to  wet 
down  the  vaults  after  the  fire  was  under  control. 

The  futility  of  constructing  standpipes  less  than  6  inches 
in  diameter  in  any  building  was  clearly  evidenced  in  this  fire. 
In  buildings  over  150  feet  high  they  should  be  8  inches.  A 
considerable  number  of  the  standpipes  in  nearby  buildings  are 
only  4  inches.  The  inefficiency  of  these  small  standpipes,  as 
compared  to  those  6  inches  in  diameter,  was  strikingly  mani- 
fested in  the  character  of  the  streams  taken  from  them. 

*  For  a  more  complete  illustrated  description  of  this  installation,  see  Journal 
of  Fire,  October,  1906. 


CHAPTER  XXXV. 
PRIVATE  FIRE  DEPARTMENTS.* 

Importance  of  -  -  The  large  concentration  of  values  repre- 
sented in  the  buildings  and  contents  of  many  modern  industrial 
plants  has  led  to  the  gradual  development,  often  to  a  very  high 
degree,  of  private  means  of  fire  protection,  especially  in  plants 
consisting  of  a  number  of  buildings.  While  automatic  sprinklers, 
automatic  alarms,  watchmen,  standpipes,  etc.,  are  invaluable  for 
coping  with  fire  under  ordinary  conditions,  special  circumstances 
often  make  advisable  a  more  complete  scheme  of  fire  protection, 
particularly  where  many  buildings  are  involved,  —  where  the 
hazards  of  manufacture  or  storage  are  great,  —  where  the  plant 
is  located  on  the  outskirts  of  a  city  or  town  where  the  municipal 
fire  department  is  insufficient  or  too  remote  for  effective  service, — 
or  in  those  localities  even  more  removed  from  centers  of  popula- 
tion where  no  adequate  public  fire  department  exists. 

The  importance  of  adequate  fire  protection .  in  large  manu- 
facturies  is  indicated  by  the  fact  that,  in  one  year,  no  less  than 
ninety-five  fires  occurred  in  the  plant  of  the  Baldwin  Locomotive 
Works,  Philadelphia. 

It  is,  therefore,  advisable,  regardless  of  how  efficient  the  ex- 
ternal sources  of  help  may  be  in  case  of  fire,  that  each  mill  or 
manufacturing  plant  should  be  a  unit  unto  itself  in  the  matter  of 
fire  protection. 

Advantages  of  Private  Protection:  In  cases  of  remote 
location  of  the  plant,  or  of  insufficiency  or  inaccessibility  on  the 
part  of  the  public  fire  department,  the  advantages  of  private 
protection  are  obvious.  But,  even  where  a  good  public  fire 
department  exists,  emergencies  may  easily  arise  wherein  the  self- 
help  would  be  all  important  —  as  where  the  public  department 
was  engaged  on  another  fire  at  a  distance,  or  delayed  by  a  heavy 
snowstorm,  or  otherwise  prevented  from  responding  promptly. 

*  See,  also,  pamphlets  "Suggestions  for  organizing  Private  Fire  Depart- 
ments," "Construction  and  Equipment  of  Hose  Houses  for  Mill  Yards"  and 
"Hydrants,"  containing  the  recommendations  of  the  National  Board  of  Fire 
Underwriters. 

974 


PRIVATE   FIRE   DEPARTMENTS  975 

Furthermore,  ample  experience  has  proven  that  the  haphazard 
efforts  of  unorganized  employees,  however  well  meant,  will  not 
control  a  fire  as  well  as  a  disciplined  force  made  familiar  with 
protective  means  and  apparatus  by  drill  and  practice;  while, 
further,  an  efficient  mill  fire  brigade,  knowing  thoroughly  the 
ins  and  outs  of  the  property,  may  well  handle  a  fire  to  even  better 
advantage  than  the  public  fire  department. 

The  following  paper  by  Mr.  R.  H.  Newbern,*  presented  at 
the  1911  annual  meeting  of  the  National  Fire  Protection  Asso- 
ciation, constitutes  one  of  the  latest,  and,  at  the  same  time,  most 
valuable  contributions  on  the  subject  of  private  fire  departments. 

Private  Fire  Brigades.  - 

The  organization  and  training  of  the  private  fire  brigade  is 
one  of  the  most  important  problems  in  the  field  of  fire  protection. 
Fire  pumps  and  distribution  systems,  however  perfect,  will  prove 
of  small  value  if  we  neglect  the  means  by  which  their  possibilities 
are  to  be  realized. 

Frequently  in  laying  out  systems  of  fire  protection  the  organi- 
zation of  the  fire  brigade  fails  to  receive  the  consideration  which 
its  importance  deserves.  It  would  seem  but  simple  business 
economy  that  the  means  whereby  the  expenditure  for  costly  in- 
stallation of  pumps,  water  mains  and  hydrants  are  to  be  made 
effective,  should  be  developed  to  its  highest  efficiency,  for  in  any 
system  of  fire  protection,  working  efficiency  will  depend  largely 
on  the  skill  with  which  it  is  handled. 

Aside  from  its  primary  object,  the  private  fire  brigade  has 
possibilities  for  the  alert  mill  manager  or  factory  superintendent 
in  promoting  amicable  relations  between  the  management  and 
employees,  which,  if  properly  developed,  will  amply  repay 
any  reasonable  expenditure  of  time  and  energy  given  to  its 
organization.  The  motive  underlying  a  fire  brigade  organization 
is  fundamentally  one  of  mutual  protection:  to  the  manager,  the 
safeguarding  and  preservation  of  his  plant;  to  the  employee,  the 
permanency  of  work  and  wage.  When  this  relationship  is  prop- 
erly understood  and  the  interest  of  each  party  made  the  common 
interest  of  both,  we  have  then  laid  the  broad  foundation  for  a 
successful  and  efficient  organization. 

Membership  in  the  brigade  should  of  itself  confer  distinction 
and,  if  possible,  carry  with  it  the  exercise  of  some  minor  privilege 
sufficiently  attractive  to  make  membership  desirable  and  sought 
after. 

Organization.  — 

The  ideal  private  fire  brigade  should  be  organized  under  a 
constitution,  with  its  own  by-laws  and  with  provision  for  regular 
stated  meetings.  The  conduct  of  the  men  within  limits  should 

*  Superintendent  of  Insurance  Department,  Pennsylvania  Railroad  Co. 


970         FIRE   PREVENTION   AND   FIRE   PROTECTION 

be  subject  to  discipline,  and  in  the  same  manner  acts  of  unusual 
merit  involving  personal  risk  and  endurance  should  be  fittingly 
rewarded. 

No  fixed  rule  can  be  followed  in  determining  the  make  up  of 
a  private  fire  brigade  which  would  be  adaptable  to  all  classes  of 
risk. 

There  are  certain  risks,  such  as  department  stores,  theatres 
and  the  older  type  of  mercantile  building,  where  occupancy  and 
character  of  construction  will  tend  to  limit  the  effective  work  of 
the  brigade  to  the  extinguishment  of  fires  in  their  early  or  in- 
cipient stage,  and  where  fire  operations  as  a  rule  will  be  confined 
to  the  interior  of  the  building.  For  other  risks,  such  as  mill  and 
shop  plants,  including  railroad  terminal  yards,  fire  operations  will 
be  mostly  in  the  open  and  generally  of  a  more  extended  character. 
It  is  clear,  therefore,  that  a  plan  of  organization  to  be  practical 
should  provide  for  the  essential  features  peculiar  to  each  of  these 
classes. 

Selection  of  Men.  — 

The  degree  of  efficiency  of  a  brigade  organization  will  be 
almost  in  exact  proportion  to  the  care  and  judgment  exercised 
in  the  selection  of  men.  Careful  selection  will  involve  judgment 
in  the  reading  and  discernment  of  character  and  a  somewhat  in- 
timate knowledge  of  the  men  and  their  personal  habits.  The 
plant  superintendent  or  store  manager,  in  performing  this  im- 
portant duty,  should  have  the  assistance  of  the  shop  foremen 
and  subheads  of  departments;  the  final  judgment,  however, 
should  be  that  of  the  superintendent  or  manager. 

In  the  work  of  selection  the  first  consideration  is  loyalty  — 
only  those  men  whose  sympathies  and  interests  are  well  known 
should  be  considered.  Fitness  for  fire  brigade  service  requires 
a  peculiar  combination  of  physical  stamina  and  judgment  —  a 
strong,  robust  constitution,  with  sight  and  hearing  unimpaired 
and  with  somewhat  more  than  ordinary  powers  of  endurance. 
The  ability  to  decide  quickly  in  emergencies  and  a  high  degree  of 
self-possession  are  qualities  most  desirable,  although  fitness  should 
not  depend  on  these  alone.  Consideration  should  be  given  to: 

Age  (ranging  between  18  years  and  45  years). 

The  ability  to  speak  and  readily  understand  English. 

A  general  knowledge  of  the  character  of  construction  and 
occupancy  of  the  building  or  plant,  including  location  of  stairways, 
elevator  shafts  and  the  means  of  approach  to  attics  and  base- 
ments. 

Proximity  of  place  of  residence  to  building  or  plant  and 
previous  experience  in  fire  department  work. 

The  Chief  of  Brigade  should  be  someone  high  in  authority 
whose  duties  would  insure  his  presence  at  the  plant  the  greater 
part  of  the  time,  preferably  the  master  mechanic  or  the  store  or  - 
factory  manager  or  his  active  assistant.  Someone  whose  position 
would  command  the  respect  of  the  men  and  give  reasonable 
assurance  of  official  recognition  for  meritorious  service. 


PRIVATE   FIRE   DEPARTMENTS  977 

Assistant  Chief.  —  This  selection  will  be  governed  by  circum- 
stances. Should  the  chief  selected  have  a  general  working 
knowledge  of  fire  protection,  the  assistant  chief  may  be  chosen 
with  reference  to  his  position  in  the  administration  of  the  plant 
or  store.  Otherwise  the  assistant  chief  should  have  some  practical 
fire  knowledge  or  mechanical  training  and  experience. 

Captains  of  Companies.  —  For  these  positions  men  with 
mechanical  knowledge  are  to  be  preferred,  either  shop  foremen, 
or  in  the  case  of  the  factory  or  department  store  someone  of  the 
regularly  employed  mechanics. 

In  addition  to  the  foregoing  qualification  they  should  be  men 
of  sound  and  reliable  judgment,  capable  of  acting  quickly  in 
emergencies,  as  upon  these  men  devolves  direct  supervision  of 
active  fire  operations  and  care  in  their  selection  is  of  the  utmost 
importance. 

Company  organization  should  be  designed  to  afford  the  men 
special  knowledge  and  experience  in  their  respective  duties.  For 
the  average  shop  plant  there  should  be  three  separate  companies; 
viz.,  hose  company,  chemical  engine  company,  and  ladder  com- 
pany, excepting  that  where  buildings  are  provided  with  a  com- 
plete equipment  of  stationary  ladders  the  latter  company  may 
be  dispensed  with.  For  the  department  store  and  factory  there 
should  be  a  chemical  engine  company  and  a  standpipe  company. 

In  addition  to  these  companies  a  special  detail  of  selected 
men  should  be  designated  to  handle  chemical  extinguishers,  fire 
pails  and  any  other  equipment.  This  latter  provision  should  not 
interfere  with  the  desirable  feature  of  having  all  employees 
thoroughly  familiar  with  the  use  and  handling  of  its  equipment. 

A  salvage  corps  consisting  of  from  six  to  twelve  men  (accord- 
ing to  size  of  plant  or  store)  should  be  maintained,  whose  special 
duties  should  consist  of  protecting  stock  and  machinery  from 
water  damage,  both  during  and  after  a  fire.  For  this  work,  men 
of  average  intelligence  are  required  who  should  be  especially 
instructed  as  to  the  proper  course  to  be  followed  in  preventing 
needless  water  damage.  The  corps  should  be  provided  with 
rubber  covers  and  other  accessories  as  the  nature  of  the  contents 
may  require. 

Assignment  of  Men  and  Duties.*  — 

Hose  Company.  —  The  minimum  requirement  for  a  hose 
company  will  vary  with  local  conditions,  but  in  no  case  should 
there  be  less  than  eight  men,  including  captain.  For  the  more 
extensive  plants  and  for  plants  having  buildings  of  large  areas 
the  organization  can  be  expanded  accordingly,  depending  largely 
upon  the  maximum  number  of  hose  streams  to  be  used. 

Hydrant  Men:  Two  men  should  be  selected  for  each  hose 
stream.  One  man  to  remain  at  hydrant  to  turn  on  and  off  water, 

*  All  employees,  especially  watchmen  and  members  of  fire  brigades,  should 
be  familiar  with  the  locations  and  use  of  all  fire  alarm  boxes  on  or  about  prem- 
ises, so  that  alarms  may  be  immediately  transmitted  to  the  city  fire  depart- 
ment. 


978         FIRE    PREVENTION   AND    FIRE    PROTECTION 

the  other  to  assist  in  unreeling  hose  and  making  couplings  and 
in  adding  or  taking  out  hose. 

In  the  runs  to  fires,  hydrant  men  should  take  position  in  the 
rear  of  hose  wagon,  one  man  (where  hydrants  are  not  provided 
with  wrenches  or  hand  wheels)  with  spanner  to  "drop  off"  on 
reaching  the  hydrant,  the  other  going  forward  with  the  hose 
wagon,  to  assist  in  unreeling  hose  and  laying  the  hose  line. 

Pipe  Director  and  Pipemen:  This  service  requires  strong, 
able  men,  capable  of  carrying  pipe  and  hose  line  up  roof  ladders, 
while  under  pressure,  and  with  endurance  to  withstand  the 
noxious  effects  of  smoke. 

Three  men  are  required  for  each  hose  line,  one  of  whom,  to 
be  designated  "Pipe  Director,"  shall  be  in  charge  of  the  pipe. 
While  nozzle  rests  and  other  devices  may  be  employed  to  control 
the  pipe  by  one  man,  the  two  additional  men  specified  will  be 
necessary  in  placing  and  moving  the  pipe  and  in  drawing  the  line 
up  ladders  and  over  roofs.  The  pipemen  in  runs  to  fires  should 
be  on  the  tongue  of  hose  wagon  and  assist  in  disconnecting  hose 
and  attaching  nozzle. 

Extra  Hosemen :  Not  less  than  two  extra  hosemen  should  be 
attached  to  each  company,  to  assist  in  drawing  hose  wagon  and 
in  laying  hose  line. 

Ladder  Company.  —  As  the  practice  of  providing  stationary 
ladders  on  buildings  of  shop  and  industrial  plants  is  now  general, 
ladder  company  service  will  be  confined  to  those  plants  not  so 
equipped,  or  where  the  equipment  is  incomplete. 

The  ladder  company  should  be  organized  with  a  complement 
of  not  less  than  nine  men,  including  a  foreman.  The  exact  num- 
ber will  vary  with  conditions,  depending  upon  height  of  buildings, 
degree  of  exposure  and  character  of  construction. 

Under  direction  of  the  foreman  the  company  will  have  entire 
charge  of  the  truck  and  ladder  equipment,  subject  to  the  orders 
of  the  chief  and  assistant  chief  of  brigade.  The  duties  of  the 
ladder  company  will  consist  of  placing  and  running  ladders, 
handling  and  use  of  chemical  extinguishers  from  the  truck's 
equipment,  and  the  opening  of  roofs,  floors,  partitions,  etc.,  as 
may  be  necessary  to  properly  play  the  hose  streams,  in  addition 
to  such  other  duties  as  in  the  judgment  of  the  chief  may  be 
necessary. 

Chemical  Engine  Company.  —  To  consist  of  five  (5)  men,  in- 
cluding a  captain. 

Tankmen :  Two  men  to  have  charge  of  operating  the  engine 
tank ;  to  open  and  close  main  tank  valve  in  addition  to  agitating 
and  mixing  the  chemical  charge,  and  of  recharging.  The  men 
should  be  thoroughly  experienced  in  both  the  principle  and 
method  of  operating  the  engine  and  should  be  held  responsible 
for  the  proper  charging  and  condition  of  the  tank  at  all  times, 
also  Cor  having  the  necessary  extra  charges  on  hand. 

Nozzlemen :  Two  men  to  be  selected  to  carry  and  direct  nozzle 
and  to  assist  in  unreeling  hose  and  laying  hose  line. 

For  engines  having  two  tanks  an  additional  tankman  and 


PRIVATE   FIRE    DEPARTMENTS  979 

nozzleman  should  be  provided.  These  men  are  mainly  necessary 
to  assist  in  drawing  the  engine. 

Standpipe  Company.  —  For  department  stores,  factories, 
large  mercantile  and  office  buildings  and  various  other  risks 
equipped  with  interior  standpipe  system,  a  separate  company 
should  be  organized  to  operate  the  system  and  to  handle  the  hose 
lines  connected  therewith. 

The  company  should  comprise  not  less  than  sixteen  (16)  men, 
or  a  sufficient  number  to  concentrate  four  hose  lines  on  any  one 
floor,  or,  where  less  than  four  connections  are  available,  there 
should  be  a  sufficient  number  of  men  to  man  all  the  lines,  as 
hereinafter  provided. 

The  company  should  be  in  command  of  a  captain,  in  direct 
charge,  and  for  each  hose  stream  there  should  be  a  valveman  and 
two  pipemen,  with  duties  as  follows: 

Valveman :  To  remain  at  hose  gate  to  turn  on  and  off  water 
and  assist  in  unreeling  hose. 

Pipemen:  To  handle  and  have  direction  of  play-pipe  and 
assist  in  unreeling  and  laying  hose  line. 

Hoseman:  For  each  hose  stream  opened  there  should  be 
one  extra  man  available  to  assist,  if  necessary,  in  unreeling  hose 
or  in  directing  play-pipe. 

Where  standpipe  systems  are  supplied  from  gravity  tanks 
or  by  means  of  connections  with  public  mains,  the  organization 
should  provide  for  a  "main  valveman,"  who  shall  be  charged 
with  the  duty  of  seeing  that  the  shut-off  valve  between  source 
of  supply  and  standpipe  system  is  open  and  in  good  working  order. 

For  all  factories  and  department  stores  there  should  be  cer- 
tain members  of  the  fire  brigade  designated  to  unreel  hose  con- 
nected with  inside  hydrants  or  standpipe  systems,  and  to  stretch 
same  carefully  on  all  floors. 

Attached  to  each  fire  brigade  organization  there  should  be 
an  experienced  plumber,  selected  from  those  connected  with  the 
plant  or  store,  preferably  one  familiar  with  the  distribution  sys- 
tem and  with  location  and  operation  of  all  valves;  also  where 
electric  current  is  used  provision  should  be  made  for  the  attend- 
ance at  aH  fires  of  a  practical  electrician,  having  first  hand  knowl- 
edge of  all  conductors,  their  voltage,  and  of  the  location  and 
operation  of  all  protective  devices.  These  men  to  report  to  the 
chief  or  assistant  chief,  and  to  be  subject  to  their  orders. 

At  plants  where  the  fire  service  is  supplied  by  fire  pumps  it  is 
advisable  to  have  the  engineer  in  charge  and  his  assistants  en- 
rolled in  the  fire  brigade  membership,  in  order  that  they  may 
be  in  close  touch  with  the  purposes  and  objects  of  the  brigade. 
During  fires,  and  except  when  prearranged  for  fire  drills,  the 
engineer  and  assistant  should  remain  on  duty  at  the  pumps. 

Fire  Drills  for  Fire  Service.*  - 

High  efficiency  for  a  fire  brigade  will  depend  upon  the  fre- 
quency and  character  of  the  fire  drills. 

*  For  fire  drills  of  inmates,  see  Chapter  XXXVII. 


980         FIRE    PREVENTION    AND    FIRE    PROTECTION 

Fire  drills  should  have  two  main  objects:  promptness  in 
reaching  the  point  of  fire  by  designated  routes,  and  practice  in 
the  handling  of  the  fire  apparatus.  To  effect  both  objects,  two 
distinct  methods  should  be  followed  in  arranging  alarms: 

First.  —  Alarms  should  be  sounded  periodically  at  irregular 
intervals  —  at  a  time  unknown  to  the  men. 

Second.  —  There  should  be,  in  addition  to  the  periodical 
alarms,  an  alarm  at  regular  stated  intervals,  semi-monthly,  at  a 
time  known  to  the  men  in  advance.  These  latter  drills  preferably 
should  be  according  to  a  prearranged  schedule  —  at  an  hour  suited 
to  the  convenience  of  the  business  or  plant  operations.  The 
drills  being  designed  for  practice  work  with  the  apparatus  will 
consume  somewhat  more  time,  as  they  will  practically  afford  the 
only  means  the  men  will  have  for  training  in  fire  department  work. 

For  department  stores  and  other  similar  risks  where  the 
public  is  present  in  large  numbers,  the  sounding  of  a  fire  alarm 
might  result  in  a  panic  and  would  be  impracticable.  For  these 
risks  fire  drills  will  necessarily  have  to  be  held  after  the  close  of 
regular  business  hours. 

When  shop  or  other  industrial  plants  are  operated  at  night, 
provision  should  be  made  for  fire  drills  similar  to  that  for  the  day 
forces.  Frequently  for  large  plants  remote  from  city  or  town 
protection,  operating  only  a  day  shift,  efficient  night  fire  brigade 
service  may  be  had  by  organizing  and  drilling  the  watchmen, 
cleaners  and  repair  men  who  may  be  regularly  employed  at  night. 
These  men  should  be  subject  to  the  same  general  rules  governing 
the  day  brigade  and  regularly  drilled  to  insure  efficient  handling 
of  all  apparatus. 

For  the  regular  semi-monthly  drills  the  brigade  work  in  the 
handling  of  apparatus  should  be  thorough  in  every  respect,  closely 
approximating  actual  fire  conditions.  It  should  embrace  the 
making  of  connections  with  hydrants,  unreeling  and  stretching 
hose,  breaking  and  making  couplings,  carrying  hose  up  ladders 
and  over  roofs  and  through  the  interior  of  buildings,  reaching  at 
various  times  inaccessible  and  out-of-way  places,  including  sub- 
basements,  basements,  attics  and  all  concealed  floor  and  wall 
spaces.  The  drills  should  cover  all  buildings  and  departments  in 
order  that  the  men  may  acquire  an  intimate  knowledge  of  the 
interior  arrangement  and  construction,  including  stairways,  exits 
and  elevator  shafts,  together  with  location  of  all  fire  hydrants  and 
connections. 

It  is  important  that  the  men  should  become  practiced  in 
holding  the  play-pipe  and  in  moving  and  carrying  the  hose  line 
while  under  pressure  and,  as  a  general  rule,  water  should  be 
turned  on  for  all  practice  work,  except  during  freezing  weather. 
At  times  when  conditions  are  favorable,  a  sufficient  number  of 
hose  lines  should  be  stretched  to  test  the  maximum  working 
capacity  of  the  distribution  system. 

The  presence  of  aerial  electric  conductors  near  a  plant  or 
building  may  operate  to  hinder  the  work  of  the  fire  brigade 
through  fear  of  the  consequence  of  contact  with  the  hose  stream. 
In  order  that  the  men  may  not  be  unnecessarily  exposed  to  these 


PRIVATE  FIRE   DEPARTMENTS 


981 


dangers  and  at  the  same  time  that  the  actual  danger  may  not  be 
over-estimated  and  thereby  delay  the  work  of  fire  extinguish- 
ment, it  is  important  that  the  men  be  fully  informed  of  actual 
conditions,  and  where  assured  of  competent  direction  during 
practice  work  it  would  be  of  considerable  advantage  to  give 
demonstrations  on  these  conductors  where  there  would  be  no 
harmful  result.  It  has  been  shown  as  a  result  of  a  series  of  tests 
that  hose  streams  of  fresh  water  may  be  played  on  a.  c.  conductors 
under  certain  conditions  without  injury  to  the  pipemen.  With  a 
one-inch  nozzle  at  a  distance  of  ten  feet  from  an  a.  c.  conductor 
carrying  4600  volts  there  was  no  appreciable  effect  beyond  a  slight 
indication  to  the  hand  of  static  electricity.  In  these  tests  one  side 
of  the  circuit  was  thoroughly  grounded  and  the  fire  stream  played 
on  the  other  side  which  was  suspended  in  the  air  and  thoroughly 
insulated. 

Hose    Houses.  —  Generally    speaking,    nothing    contributes 
more  to  the  efficiency  of  a  private  (or  public)  fire  brigade  than 


FIG.  394. —  "National  Standard"  Yard  Hose  House. 

the  ability  to  "get  water  on  the  fire;"  hence  delay  caused  by 
bringing  hose  and  other  appliances  from  some  distant  point  of 
the  plant  may  result  in  a  serious  fire,  when,  had  hose  been  acces- 
sible at  each  hydrant,  little  loss  would  be  probable.  Also,  it 
should  be  remembered  that  hose,  if  rubber  lined,  deteriorates 
rapidly  when  kept  in  heated  rooms,  while,  in  the  case  of  fire,  hose 


982         FIRE   PREVENTION   AND   FIRE   PROTECTION 

and  all  other  appliances  within  buildings  may  be  quickly  made 
inaccessible.  Hence  both  efficiency  and  economy  make  ad- 
visable the  use  of  yard  hose  houses,  wherein  hose  may  be  attached 
to  the  hydrants,  ready  for  use,  under  conditions  of  ventilation 
which  will  materially  contribute  to  the  life  of  the  hose. 

Such  hose  houses  should  preferably  be  of  the  "  National  Stand- 
ard" type,  as  approved  by  the  Associated  Factory  Mutual  Fire 
Insurance  Companies,  the  National  Board  of  Fire  Underwriters, 
and  the  National  Fire  Protection  Association. 

Fig.  394*  illustrates  a  hydrant  house  which  is  recommended 
for  all  hydrants,  and  especially  for  three-  and  four-way  hydrants, 
as  the  attachment  of  the  hose  to  the  side  outlets  of  the  hydrant 
is  made  possible  without  any  sharp  bends.  For  the  fourth  (or 
rear)  outlet,  a  7-inch  hole  should  be  cut  in  the  back  of  the  house 
under  the  lower  shelf,  as  otherwise  the  sharp  bend  necessary  in 
the  hose  would  prevent  the  flow  of  water.  Both  floor  and  shelves 
should  be  laid  slatted  (not  solid),  so  as  to  allow  the  free  circula- 
tion of  air. 

Three-  and  four-way  hydrants  should  always  be  of  type  having 
independent  gates  for  each  outlet. 

Fig.  395*  illustrates  another  design  of  hose  house  wherein  the 
hydrant  should  be  set  as  close  to  the  front  door  as  possible,  allow- 
ing only  sufficient  room  inside  the  door  for  the  attachment  of 
hose  to  outlet. 

Whatever  the  particular  design,  hose  houses  should  always  be 
built  with  brick  pier  foundations  carried  somewhat  above  the 
level  of  the  surrounding  ground,  and  with  the  earth  sloped  up 
toward  it,  so  that  good  drainage  may  be  secured,  and  the  bank- 
ing up  of  snow  obviated  as  far  as  possible.  The  doors  should 
swing  at  least  one  foot  clear  of  the  ground.  Ventilation  should 
be  provided  by  making  a  li-inch  space  around  the  top  of  the 
house,  between  the  tops  of  the  walls  and  an  apron  board,  sus- 
pended from  the  under  side  of  the  overhanging  roof. 

Equipment  for  Hose  Houses. —  The  Associated  Factory 
Mutual  Fire  Insurance  Companies  recommend  the  following 
equipment  for  each  hose  house: 

One  hundred  feet  of  cotton  rubber-lined  Underwriters'  hose, 
to  be  always  coupled  to  hydrant,  and  with  play-pipe  attached. 
At  least  100  feet  of  extra  hose,  coiled  on  upper  shelf. 

*  For  framing  diagrams,  etc.,  see  pamphlet  "Construction  and  Equipment 
of  Hose  Houses  for  Mill  Yards,"  issued  by  National  Board  of  Fire  Underwriters. 


PRIVATE   FIRE   DEPARTMENTS 


983 


Two  axes,  two  bars,  four  spanners  (Tabor  type),  two  addi- 
tional standard  Underwriters'  play-pipes>  two  ladder  straps,  one 
nozzle  holder  and  one  heavy  mill  lantern. 

One  wrench  should  always  be  kept  on  hydrant,  and  a  spare 
one  provided  for  emergency.  Large  hand- wheels  on  all  yard 
hydrants  are,  however,  the  best. 

A  supply  of  large  sponges  with  elastic  bands  to  slip  over  the 
head  are,  when  wet,  most  useful  to  assist  men  to  enter  smoky 
rooms. 

In  large  mill  yards  it  is  best  to  keep  part  of  the  additional 
hose,  etc.,  on  a  well-equipped,  two-wheel  carriage,  as  it  can  be 
more  quickly  transported  to  different  parts  of  the  yard. 


FIG.   395. —  "National  Standard"  Yard  Hose  House. 


Hose:   Cotton  Rubber-lined.  — 

For  use  on  the  yard  hydrants  of  the  ordinary  factory,  we 
recommend  unjacketted  cotton  rubber-lined  hose.  Specify  that 
it  be  guaranteed  conformable  to  specifications  of  Associated 
Factory  Mutual  Fire  Insurance  Companies. 

For  nine-tenths  of  the  factory  yards  the  above  hose  is  prefer- 
able to  the  thicker  and  heavier  jacketted  hose  used  by  the  city 
fire  departments,  as  it  is  easier  to  handle  and  more  quickly  dried 
and  more  economical  for  the  consumer. 

It  will  not  become  cut  or  injured  by  chafing  nearly  so  easily 
as  does  linen  hose  when  lying  over  sharp  corners,  and  when  sub- 
ject to  the  slight  vibrations  due  to  pulsations  of  the  fire  pump. 
There  is  also  much  less  loss  of  pressure  by  friction  in  well-made 


984         FIRE   PREVENTION   AND   FIRE   PROTECTION 

rubber-lined  hose  than  in  linen,  and  this  makes  an  important 
difference  in  the  jet  when  length  of  hose  is  more  than  150  feet. 
For  rolling  mills  or  yards  containing  rough  storage,  liable 
to  entail  heavy  wear,  the  same  hose  may  be  used  with  addition 
of  a  jacket  composed  of  the  same  kind  of  cotton  fabric,  thus 
forming  an  excellent  "fire  department  hose."  For  chemical 
works  or  similar  yards,  where  acids  might  injure  the  cotton  fabric, 
we  recommend  solid  rubber  hose.* 

No  hose  smaller  in  diameter  than  2f  inches  should  be  used. 
The  actual  inside  diameter  of  the  so-called  2J-inch  Underwriters' 
hose  is  2 f  inches. 

Care  of  Rubber-lined  Fire  Hose.  —  Experience  has  shown  that 
a  good  cotton  rubber-lined  hose,  properly  cared  for,  will  fre- 
quently last  ten  or  even  fifteen  years. 

Do  not  allow  hose  to  remain  on  reels,  or  in  wagons,  if  wet  or 
muddy,  but  remove  all  mud  by  washing  or  brushing,  and  expose 
hose  to  air,  in  towers,  or  on  racks  and  preferably  at  full  length,  to 
dry. 

Good  makes  of  fire  hose  are  antiseptically  treated,  and  will 
not  mildew  or  rot  if  given  ordinary  fire  department  care;  but 
continued  dampness  is  injurious  to  cotton  fabrics,  and  mud  fre- 
quently contains  metallic  or  other  substances  that  are  chemically 
injurious  to  hose,  if  permitted  to  remain  on  it. 

Unless  hose  is  likely  to  encounter  a  freezing  temperature,  it 
is  not  necessary  to  drain  the  water  entirely  from  rubber-lined 
hose,  for  the  rubber  lining  is  not  injured  by  dampness  within  it; 
but,  on  the  contrary,  it  is  benefited  by  remaining  in  a  moist  con- 
dition. All  rubber-lined  hose  should  have  water  passed  through 
it,  at  least  two  or  three  times  a  year,  to  moisten  the  rubber. 

Hose  is  liable  to  crack  if  bent  while  frozen.  Extreme  cold 
probably  causes  a  slight  deterioration  of  rubber,  but  not  enough 
to  prevent  the  storage  of  hose  in  cold  hose  houses. 

It  is  desirable  to  avoid  the  exposure  of  rubber  hose  and  of 
rubber  linings  to  very  hot,  dry  air;  and  hose  shoijld  not  be  stored 
where  exposed  to  the  sun's  rays.  When  hose  must  be  kept  in 
hot  and  dry  places,  it  is  best  to  pass  water  through  it  monthly. 

It  is  better  to  avoid  short  bends  in  hose  of  any  kind,  but 
when  necessary  to  store  hose  in  folds,  the  folds  should  be  changed 
occasionally  to  avoid  permanent  set.f 

Hydrant  Pipes  vs.  Hose. 

The  following  computation  shows  the  economy  of  pipes  and 
hydrants,  as  compared  with  hose: 
First.     EFFICIENCY. 
(a)  With  600  gallons  of  water  per  minute  flowing  in  6-inch 

*  From  Inspection  Department  of  the  Associated  Factory  Mutual  Fire 
Insurance  Companies. 

t  See  Isaac  B.  Markey,  in  "  1907  Proceedings  of  International  Association  of 
Fire  Engineers." 


PRIVATE   FIRE   DEPARTMENTS  985 

pipe  having  an"  ordinary  amount  of  rust  in  it,  a  pressure  of  75 
pounds  can  be  maintained  at  the  hydrant,  with  a  pressure  not 
over  110  pounds  at  the  pumps  1000  feet  distant,  and  this  would 
give  two  streams  through  50-foot  lines  of  hose  and  1  J-inch  nozzles, 
with  60  pounds'  pressure  at  nozzles. 

(6)  This  same  pressure  of  110  pounds  would  deliver  through 
1000  feet  of  best  cotton  rubber-lined  hose  and  a  l|-inch  nozzle 
only  190  gallons  of  water,  while  the  pressure  at  nozzles  would  only 
be  25  pounds,  which  pressure  can  hardly  be  considered  fair  for  a 
fire  stream. 

The  great  superiority  of  the  pipe  over  hose  is  therefore 
evident  as  it  would  require  256  pounds'  pressure  at  pump  to 
deliver  600  gallons  of  water  through  two  1000-foot  lines  of  C.  R.  L. 
hose  with  IJ-inch  nozzles.  This  is  manifestly  impracticable. 

Second.     COST. 

(a)  1000  feet  6-inch  C.  I.  pipe  at  0.98    .    .       $980.00 
One  two-way,  frostproof  hydrant    ...  30.00 
100  feet  2|-inch  C.  R.  L.  Underwriter 

hose 65.00 

Two  nozzles 10.00 

$1085.00 

(b)  Two  lines  of  1000  feet  each  2f -inch  C.  R. 

L.  Underwriter  hose  at  0.60  per  foot    .        1200. 00 
Two  nozzles    .  10.00 


$1210.00 

Difference,  $125  in  favor  of  C.  I.  pipe. 
Third.     DURABILITY  AND  QUICKNESS  IN  SERVICE. 

As  regards  these  there  can,  of  course,  be  no  comparison, 
as  every  consideration  is  in  favor  of  the  pipe.* 

*  See  "Slow-Burning  or  Mill  Construction,"  Boston  Manufacturers'  Mutual 
Fire  Insurance  Co.,  Revised  Edition,  1908. 


CHAPTER  XXXVI. 

INSPECTION    AND    MAINTENANCE    OF    FIRE     PRO- 
TECTIVE DEVICES. 

Importance  of  Inspection  and  Maintenance.  —  The  value 
of  fire-resisting  equipment,  whatever  its  nature,  is  dependent 
upon  effective  maintenance  and  proper  working  order.  Efficient 
maintenance  is  particularly  vital  to  the  insurance  companies  who 
insure  property  containing  such  equipment,  for  the  obvious  reason 
that  definite  rates,  probably  involving  allowances  or  deductions 
in  premiums,  are  fixed  on  the  assumption  of  the  effective  opera- 
tion of  such  equipment.  But  the  insured  often  seem  interested 
principally  in  securing  insurance  rates  as  low  as  may  be  possible, 
thereafter  leaving  the  equipment  to  care  for  itself,  without 
adequate  inspection  or  repair,  and  often  without  the  supervision 
or  charge  of  some  one  familiar  with  operation.  The  idea  of  look- 
ing at  fire-resisting  equipment  in  the  nature  of  an  investment,  — 
an  investment  against  fire  loss,  interruption  to  business,  or 
against  increased  insurance  premiums,  • —  which  will  return  good 
dividends  in  the  economies  and  safeguards  provided,  does  not 
seem  to  strike  many  owners  in  any  light  comparable  to  the  in- 
vestment of  an  equal  amount  of  money  in  any  branch  of  their 
active  operations.  And  yet  the  neglect  of  such  equipment  may 
and  often  does  mean  quite  as  sure  a  financial  loss  as  carelessness 
or  oversight  in  regular  business  matters. 

AUTOMATIC   SPRINKLERS. 

In  Chapter  XXX  the  statement  was  made  that  the  fire  risk 
in  any  ordinary  mercantile  or  manufacturing  building,  which  is 
protected  by  an  adequate  and  approved  automatic  sprinkler 
system,  becomes  almost  nil,  provided  the  system  is  properly  in- 
spected and  maintained.  The  typical  sprinkler  fires  described  in 
the  same  chapter,  and  the  data  concerning  the  efficiency  of 
sprinkler  installations  or  the  causes  of  their  failure  —  as  shown 

986 


MAINTENANCE   OF   FIRE   PROTECTIVE   DEVICES      987 

by  the  tabulated  records  of  the  National  Fire  Protection  Asso- 
ciation —  warrant  the  same  general  conclusion,  namely,  that 
automatic  sprinklers  will  usually  accomplish  all  that  may  reason- 
ably be  expected  of  them,  if  the  installation  is  kept  in  proper 
repair  in  full  effective  working  order. 

Careful  inspection  and  maintenance  of  sprinkler  systems,  of 
whatever  type,  are  therefore  of  paramount  importance. 

Statistics  of  sprinkler  fires  show  conclusively,  as  was  more 
fully  pointed  out  in  Chapter  XXX,  that  the  greatest  losses  are 
not  due  to  excessive  or  unreasonable  demands  made  upon  the 
sprinkler  equipment,  but  to  the  system  being  out  of  order  or 
inoperative  at  the  critical  moment,  through  causes  which  are 
usually  remediable  with  intelligent  supervision  and  maintenance. 

Such  causes  are,  primarily,  weak  and  defective  water  supplies 
and  closed  valves.  Other  causes  include  freezing  of  water  in 
pipes  or  tanks,  defective  or  inoperative  heads,  obstruction  to 
distribution,  improper  repairs,  ill-considered  changes  made  in 
premises,  and  lack  of  supervision  and  familiarity  with  apparatus. 
These  possibilities  and  their  proper  correction  will  be  briefly  out- 
lined, especially  from  the  standpoint  of  installations  where  central 
station  supervisory  service  is  not  employed.  Of  course  such 
features  of  maintenance  and  proper  working  order  as  water-flow 
alarm,  closed  valves,  freezing  of  tanks,  low  air-  or  steam-pressure, 
etc.,  are  most  adequately  guarded  against  through  central  station 
connection  and  supervision,  as  described  in  Chapter  XXXI, 
page  919. 

Water  Supplies.  —  Points  requiring  particular  attention  are 
as  follows: 

Two  independent  water  supplies  should  be  maintained  under 
sufficient  pressure  at  all  times,  but  if  one  supply  is  temporarily 
out  of  service,  —  as  during  necessary  repairs,  —  the  secondary 
supply  must  be  in  perfect  working  order  and  maintaining  good 
pressure  on  all  sprinklers  and  other  parts  of  the  equipment. 

The  water  supply  must  not  be  obstructed  by  means  of  water 
meters  or  pressure  regulating  valves. 

Gravity  tanks  should  be  kept  full,  and  both  tanks  and  pipes 
connecting  to  same  must  be  amply  protected  against  freezing. 
Tanks  may  be  heated  by  attaching  near  base  of  tank  riser  a  so- 
called  "tank  heater"  which  operates  by  hot  water  circulation. 
A  coil  inside  the  heater  is  attached  to  the  steam  supply.  The 
water  in  the  shell  of  heater,  surrounding  the  coil,  passes  up  to 


988         FIRE   PREVENTION   AND   FIRE   PROTECTION 

the  tank  through  a  small  flow  pipe.  The  return  circulation  is 
taken  from  the  tank  riser,  where  a  thermometer,  on  the  return 
pipe,  shows  the  temperature  of  coldest  water  in  tank  or  riser. 
If  the  tank  is  exposed  to  the  weather,  a  double  cover  —  the  upper 
to  be  conical  in  shape  —  with  air-space  between,  is  also  necessary. 

Pressure  tanks  should  be  kept  two-thirds  full  of  water  and 
under  adequate  air-pressure. 

Steam  fire  pumps  should  be  maintained  with  steam  pressure 
at  the  throttle  valve  at  all  times.  They  should  be  tested  weekly 
by  discharging  full  capacity  through  the  relief  valve,  in  addition 
to  which  a  complete  test  should  be  made  two  or  three  times  a 
year. 

Rotary  pumps  should  be  turned  over  weekly,  and  given  a  com- 
plete test  two  or  three  times  a  year.  They  should  also  be  kept 
well  oiled,  as  "rust  and  usage  will  impair  the  efficiency  of  a  rotary 
pump  more  quickly  and  to  a  much  greater  degree  than  of  an 
Underwriters'  steam  pump."* 

Valves.  —  In  Chapter  XXX,  dealing  with  automatic  sprin- 
klers, etc.,  the  subject  of  valves  was  left  for  later  consideration  for 
the  reason  that  this  detail  of  sprinkler  installation  is  most  in- 
timately connected  with  and  dependent  upon  careful  inspection. 
There  is  little  doubt  that  more  so-called  sprinkler  " failures"  have 
been  due  to  closed  valves  than  to  most  other  causes  of  failure 
put  together. 

The  principal  valves  used  in  sprinkler  systems  are  of  two 
general  types  —  those  located  on  the  main  piping  connecting  to 
water  supplies,  and  those  located  on  the  distributing  or  sprin- 
kler supply  pipes.  All  of  these  must  be  of  the  "outside  screw  and 
yoke"  or  other  approved  indicator  pattern. 

For  the  piping  connecting  each  source  of  water  supply  with 
the  sprinkler  system,  approved  practice  requires  separate  gate- 
and  check- valves. 

"Gate-valves  should  be  located  close  to  the  supply,  as  at  the 
tank,  or  near  base  of  tank  trestle,  pump,  or  in  the  pipe  connecting 
the  riser  with  the  water  works  system."f 

It  is  not  always  advisable  to  follow  this  rule  literally  in  con- 
nection with  gravity  tank  supplies.  For  instance,  if  tank  is  on 
a  trestle,  gate-valve  should  be  at  bottom  of  trestle,  preferably  a 
post  indicator-valve  in  the  underground  pipe  near  where  tank 

*  Crosby  and  Fiske. 

t  Rules  and  Requirements  of  National  Board  of  Fire  Underwriters. 


MAINTENANCE   OF   FIRE   PROTECTIVE   DEVICES      989 

riser  enters  ground.  If  tank  is  on  a  framework  over  roof  of 
building  or  over  a  tower,  and  gate-valve  is  located  directly  under 
tank,  it  would  be  difficult  of  access  and  hard  to  inspect.  It 
should  be  located  in  the  nearest  available  place,  such,  for  in- 
stance, as  the  upper  story  of  building.* 


Check-valves  must  be  of  "  straightway "  pattern,  placed  pref- 
erably in  horizontal  position,  unless  especially  designed  for  ver- 
tical position.  Underground  check- valves  should  be  located  in 
pits,  which  should  be  accessible  through  man-holes,  tight  enough 
to  exclude  ground-  or  surface-water,  and  proof  against  freezing. 
Check-valves  should  always  be  easy  of  access,  as  they  require 
occasional  repairing  or  cleaning  out. 

Valves  on  Sprinkler  Supply  Pipes.  —  The  rules  of  the  National 
Board  require  "each  system  to  be  provided  with  a  gate- valve  so 
located  as  to  control  all  sources  of  water  supply  except  from 
steamer  connections.  All  gate- valves  controlling  automatic 
water  supplies  for  sprinklers  should  be  located  where  easily 
visible  and  readily  accessible."  In  other  words,  there  must  be 
one  gate- valve  on  every  system  of  piping  which  can  be  closed  at 
a  moment's  notice,  thereby  shutting  off  every  automatic  water 
supply.  This  is  to  prevent  the  water  damage  which  would  other- 
wise ensue  from  broken  or  defective  heads,  or  from  heads  con- 
tinuing to  discharge  after  having  accomplished  their  office  by 
extinguishing  some  small  blaze.  The  accessibility  of  sprinkler 
valves  is,  therefore,  very  important;  for  if  concealed  or  ob- 
structed by  stock  or  goods,  or  if  placed  beyond  easy  reach,  much 
valuable  time  may  be  lost  before  possible  water  damage  could  be 
discontinued.  If  valves  are  located  so  that  they  cannot  be 
reached  from  the  floor,  a  permanent  ladder  should  be  provided. 

Sprinkler  gate-valves  must  be  kept  open.  This  is  axiomatic, 
and  yet  the  experience  of  those  entrusted  with  the  inspection  of 
sprinklered  risks  shows  that  literally  hundreds  of  installations 
are  rendered  null  and  void  every  year,  for  greater  or  less  periods 
of  time,  because  one  or  more  sprinkler  valves  are  closed.  The 
National  Fire  Protection  Association's  statistics  of  unsatisfactory 
sprinkler  fires,  before  quoted,  show  that  23  per  cent,  of  such  fires 
for  the  years  1897  to  1911,  inclusive,  were  due  to  water  being 
shut  off  —  usually  for  "  unknown  reason,  neglect  or  careless- 
ness." The  condition  of  sprinkler  valves,  and,  in  fact,  of  all 

*  "Hand-Book  of  Fire  Protection  for  Improved  Risks,"  Crosby  and  Fiske. 


990         FIRE    PREVENTION    AND    FIRE    PROTECTION 

valves  on  the  system,  therefore  constitutes  the  most  important 
feature  in  sprinkler  inspection  and  maintenance. 

The  best  method  of  providing  against  closed  valves  is  through 
the  use  of  central  station  supervisory  service,  as  explained  in 
Chapter  XXXI,  page  919;  but  if  such  supervision  is  not  avail- 
able, or  is  not  used,  each  valve  should  be  secured  open  by  means 
of  a  leather  strap  with  a  ring  riveted  to  each  end,  through  which 
a  padlock  can  be  inserted  and  locked.  In  case  of  emergency,  —  as 
to  prevent  water  damage,  —  the  strap  can  be  cut;  but  otherwise, 
accidental  or  careless  closing  could  only  be  accomplished  wil- 
fully. The  keys,  which  should  be  of  uniform  pattern  for  all 
padlocks,  should,  of  course,  be  entrusted  only  to  those  in  re- 
sponsible charge  of  the  system.  It  is  essential  that  some  one 
man  be  held  responsible  for  the  condition  of  all  valves,  and,  to 
provide  for  his  possible  absence,  an  assistant  should  be  added. 
Both  should  be  thoroughly  familiar  with  the  location,  operation 
and  uses  of  all  valves,  and  keys  to  valve  padlocks  should  be  in 
no  other  hands  save  one  at  the  office  of  plant  or  building  for 
use  of  owner  or  superintendent. 

Inspection.  —  All  valves  should  be  inspected  at  least  weekly, 
or  preferably  daily.  A  check  inspection,  say  weekly,  by  some 
independent  employee,  is  also  to  be  recommended  to  prevent 
carelessness  on  the  part  of  those  held  directly  responsible.  Rec- 
ords should  be  kept  of  all  regular  inspections,  giving  data  as  to 
condition  of  valves,  when  and  why  closed,  and  when  re-opened. 
(See  later  paragraph  "  Self-inspection  by  the  Property  Owner.") 

The  inspection  of  gate-valves  should  include  giving  a  quarter- 
turn  to  make  sure  that  they  can  be  operated  in  time  of  need. 
This  is  of  especial  importance  where  corrosive  tendencies  are 
present. 

The  tagging  or  labeling  of  gate-valves  is  also  advisable,  so 
that  in  time  of  emergency  there  may  be  no  question  as  to  just 
what  system  or  systems  each  valve  controls. 

Valves  intended  to  be  used  only  in  case  of  repairs  should  be 
locked  open  by  chains,  rather  than  strapped,  to  prevent  tam- 
pering with. 

Freezing  of  Water  in  Pipes.  —  Lack  of  water  in  sprinkler 

systems  results  more  frequently  from  freezing  than  from  any 

other  cause  save  carelessly  closed  gate-valves.     It  is  therefore  a 

fundamental   requirement    that    buildings    containing   wet-pipe 

.  sprinkler  installations  must  be  adequately  heated  throughout, 


MAINTENANCE    OF    FIRE   PROTECTIVE   DEVICES      991 

for  a  " freeze-up"  in  the  piping  or  at  sprinkler  heads  may  not 
only  cause  the  temporary  tie-up  of  the  system  until  it  can  be 
thawed  out,  but  may,  also,  result  in  serious  water  damage. 
Special  watchfulness  is  therefore  necessary  in  severe  freezing 
weather,  particularly  at  such  exposed  or  poorly  heated  locations 
as  hallways,  attics,  towers,  dormer  windows,  roof  monitors,  etc., 
as  well  as  near  open  windows,  transoms  or  ventilators,  where  the 
ordinary  requirements  of  ventilation  will  sometimes  be  sufficient 
to  freeze  nearby  heads. 

In  a  recently  completed  retail  store  building  in  Boston,  a 
sprinkler  pipe  extending  into  an  unheated  freight  elevator  shaft 
became  so  frozen  during  a  spell  of  very  cold  weather  that  the 
expansion  of  the  ice  in  the  piping  caused  the  breaking  off  of  a 
section  several  feet  long.  The  first  knowledge  of  the  matter 
was  upon  the  discovery  of  the  section  at  the  bottom  of  the  shaft. 
Great  water  damage  was  prevented  only  by  the  remaining  stub 
of  the  piping  being  also  frozen  solid. 

Dry-pipe  systems  must  be  carefully  drained  to  see  that  no 
water  collects  or  remains  in  the  piping.  If  the  system  is  con- 
verted from  a  wet-pipe  into  a  dry-pipe  system  during  cold 
weather,  the  drip  pipe  should  be  opened  and  tested  for  several 
consecutive  days  after  the  change,  in  order  to  insure  the  drainage 
of  all  water. 

Testing  Water  Pressure.  — 

A  simple  and  effective  method  of  testing,  to  determine 
whether  there  is  water  in  the  pipes  under  pressure,  is  by  means 
of  the  drip  or  drain  pipe,  located  usually  over  or  near  the  shut-off 
valve.  On  the  main  feed  pipe,  about  a  foot  beyond  the  drip  pipe, 
there  should  be  a  pressure  gauge  which  registers  ordinarily  the 
normal  or  static  pressure.  Frequent  reading  of  the  gauge  will 
show  the  normal  pressure,  provided  water  is  discharged  at  some 
point  in  sufficient  quantity  to  relieve  any  excess  pressure  that 
may  be  "bottled  up"  in  the  system  and  held  there  by  the  check- 
valves.  Any  material  variation  from  the  normal  pressure  is 
easily  determined. 

Normal  or  static  pressure,  however,  is  not  conclusive  evi- 
dence of  the  condition  of  the  water  supply,  the  real  question 
being  as  to  whether  the  pressure  will  be  maintained  approxi- 
mately in  case  of  a  drain  on  the  system,  such  as  occurs  when 
several  sprinklers  operate.  The  proper  way  to  determine  this 
point  is  to  opeti  wide  the  drain  or  drip  pipe  and  note  the  drop  in 
pressure  at  the  gauge.  These  drip  pipes  are  usually  1^  or  2  inches 
in  diameter,  and,  with  a  good  water  supply,  the  drop  in  pressure 
should  not  be  more  than,  say,  10  per  cent.,  it  being  generally  much 


992         FIRE   PREVENTION    AND   FIRE    PROTECTION 

less  than  that.  If  the  drop  be  more  than  25  per  cent.,  it  shows 
probably  either  a  weak  water  supply  or  trouble  somewhere,  such 
as  a  partly  closed  valve  or  clogged  feed  pipe.  A  few  tests  under 
known  normal  conditions  will  establish  the  drop  in  pressure  for 
any  particular  system,  and  any  material  change  calls  for  further 
investigation.  While  a  test  of  this  kind  does  not  prove  an  un- 
limited or  unobstructed  water  supply,  it  does  determine  to  some 
extent  that  approximately  normal  conditions  exist.  It  is  not 
necessary,  nor  is  it  generally  desirable,  to  leave  the  drip  valve 
open  for  any  length  of  time.  If  the  pressure  continues  to  drop 
little  by  little,  there  is  probably  trouble  of  a  serious  nature.  The 
drip  pipe  should  always  have  an  unobstructed  outlet,  with  pro- 
vision for  taking  care  of  any  water  that  may  be  discharged. 

The  test  pipe  generally  provided  at  top  of  a  riser  is  of  little 
if  any  value  in  determining  the  condition  of  the  water  supply. 
Such  pipes  are  usually  one-half  inch  in  diameter,  and  the  amount 
of  water  discharged  can  have  but  very  little  effect  on  the  pressure. 

A  weekly  test  of  the  drip  pipe  would  not  seem  too  frequent, 
and  the  gauges  should,  of  course,  be  inspected  daily,  particularly 
the  gauge  on  the  water  supply  pipe  before  it  reaches  the  con- 
trolling valve,  for  that  gauge  would  generally  show  whether  the 
supply  is  in  service. 

Too  much  emphasis  cannot  be  laid  on  the  value  of  the  water  flow, 
or  drip  pipe  test.  By  means  of  this  test  inspectors  frequently 
find  important  defects,  such  as  post  gates  closed  where  they  read 
"open,"  and  water  works  gates  partly  or  nearly  closed.* 

Defective  '  Heads:  Corrosion.  —  The  prompt  automatic 
action  of  the  sprinkler  heads  is,  of  course,  almost  as  important  a 
consideration  as  the  presence  of  ample  water  supply.  Without 
sufficient  water  supply  and  pressure,  sprinkler  heads  are  of 
little  value;  and,  conversely,  the  best  of  water  supplies  is  of 
little  use  unless  automatically  controlled  by  sensitive  and  reliable 
heads.  The  inspection  of  sprinkler  heads  is,  therefore,  of  the 
most  vital  importance,  and  deterioration,  disintegration  /and 
corrosion  must  be  guarded  against  to  insure  that  protection 
which  is  expected  of  a  sprinkler  installation. 

In  only  too  many  instances  the  sprinkler  heads,  after  once 
being  installed,  are  left  to  care  for  themselves,  and  dirt,  dust, 
lint  and  other  floating  particles  are  allowed  to  accumulate  upon 
them  until  the  reliability  of  the  head  action  is  a  serious  question. 
Sprinkler  heads  should  therefore  be  dusted  or  cleaned  as  often 
as  may  be  necessary  to  keep  them  clean  and  bright  and  as  near 
their  original  condition  as  possible.  Whitewashing,  painting, 
gilding,  etc.,  of  heads  should  never  be  permitted,  as  the  sensitive- 

*  See  "The  Care  of  Automatic  Sprinkler  Systems,"  by  H.  A.  Fiske,  Insur- 
ance Engineering,  January,  1907. 


MAINTENANCE   OF   FIRE   PROTECTIVE   DEVICES      993 

ness  and,  indeed,  the  very  operation  of  the  struts  or  valves  is 
irreparably  injured. 

Disintegration  and  corrosion  are  also  sources  of  danger,  due 
to  the  action  of  acid  fumes  or  vapors  upon  the  metallic  portions 
of  the  heads.  Hence  in  manufacturing  plants  employing  such 
acids  as  nitric,  sulphuric  or  muriatic,  disintegration  or  chemical 
changes  are  liable,  in  time,  to  cause  the  failure  of  the  fusible 
solder,  or  the^adhesion  of  different  metallic  parts,  so  as  to  make 
the  head  inoperative.  In  such  plants,  and  indeed  in  all  cases 
where  normal  atmospheric  conditions  are  not  present,  more  than 
ordinary  care  must  be  taken  to  see  that  all  heads  are  frequently 
inspected,  and,  in  case  of  doubt,  tested.  Whenever  wiping  or 
ordinary  brushing  does  not  show  the  sprinkler  to  be  clean  and 
bright,  there  is  likely  to  be  danger. 

Corrosion  Tests,  recommended  by  the  Western  Factory  In- 
surance Association  of  Chicago,  are  as  follows: 

Ordinary  corrosion  tests  are  Nos.  1  and  2  as  below.  Test 
sprinkler  heads  exposed  to  corrosive  influences  by  any  or  all  of 
the  following  tests: 

1.  Test  any  portion  of  the  exposed  fusible  solder  by  apply- 
ing the  point  of  a  knife  like  a  chisel.     Note  whether  the  solder 
will  curl  or  twist  as  a  chip.     If  the  solder  is  brittle,  or  crumbles 
and  will  not  curl,  the  sprinklers  have  failed  to  pass  the  test. 

2.  Plunge  the  sprinkler  into  hot  fluid,   approximately  50 
degrees  hotter  than  the  theoretical  fusing  point  of  the  sprinkler. 
Note  if  it  opens  satisfactorily  within  30  seconds.     For  ordinary 
sprinklers  this  test  does  not  require  a  thermometer,  as  boiling 
water  is  50  degrees  hotter  than  a  162-degree  head. 

3.  Test  sample  sprinklers  in  the  field  in  a  japan  oven,  dry- 
kiln  or  other  factory  hot  box,  allowing  time  at  discretion  and  50 
degrees  higher  temperature  than  the  theoretical  fusing  points  of 
the  heads.     Note  if  sprinkler  fuses  properly.  fj 

Failure  to  pass  any  of  the  above  tests  may  be  taken  as  suffi- 
cient ground  for  requiring  renewal  of  the  sprinklers.  It  must 
be  borne  in  mind  that  corrosion  sometimes  seriously  affects  sol- 
der, although  the  head  may  show  very  little  injury.  In  other 
cases  the  head  may  look  very  badly,  but  not  be  much  injured. 

Sprinkler  heads  subject  to  corrosive  tendencies  should  always 
be  protected  by  some  anti-corrosive  coating,  at  the  time  of  initial 
installation,  and  not  while  in  place  after  corrosion  has  started. 
One  of  the  best  protections  is  a  wax-like  coating  called  "Corro- 
proof."  Paraffine,  paint,  lead  coatings  and  asphaltum  have 
generally  been  found  to  be  of  little  protection,  if  not  absolute 
failures. 


994         FIRE   PREVENTION   AND   FIRE    PROTECTION 

"Hard-heads,"  or  sprinklers  operating  at  high  temperatures, 
should  be  used  as  sparingly  as  possible.  The  records  of  sprinkler 
fires  show  that  inoperative  heads  of  this  character  have  been  the 
cause  of  serious  fires. 

There  should  be  maintained  on  the  premises  a  supply  of 
extra  sprinklers  (never  less  than  six)  to  replace  promptly  any 
fused  by  fire  or  in  any  way  injured.* 

Interference  to  Distribution.  —  It  has  been  stated  in  Chap- 
ter XXX  that  sprinkler  protection  is  based  upon  the  principle  of 
controlling  fire  at  its  point  of  origin,  thus  insuring  a  minimum 
fire  damage  through  the  use  of  a  minimum  supply  of  water. 
Manifestly  this  result  can  be  secured  only  by  allowing  each 
individual  sprinkler  head  fully  to  wet  down  the  area  of  floor 
space  allotted  to  it,  and  if  either  permanent  or  temporary  ob- 
structions to  such  distribution  of  water  are  allowed  to  exist,  the 
whole  scheme  of  sprinkler  protection  is  vitiated. 

If  the  original  installation  is  made  in  conformity  with  the  best 
practice,  all  such  locations  as  have  previously  been  mentioned 
(in  Chapter  XXX)  would  be  supplied  with  sprinklers,  but  tenants 
are  later  very  apt  to  introduce  shelving,  benches  or  large  tables, 
overhead  storage  racks,  platforms,  etc.,  all  of  whichjorm  water- 
sheds which  introduce  a  large  element  of  danger.  When  any 
such  features  are  introduced,  the  necessary  heads  should  be  added 
at  once. 

In  addition  to  the  above  mentioned  permanent  obstructions, 
temporary  interference  to  water  distribution  is  often  caused 
by  the  stacking  up  of  stock  or  contents  to  too  great  a  height. 
"  Sprinkler  heads  must  be  kept  free  to  form  an  unbroken  spray 
blanket  for  at  least  two  feet  under  the  ceiling  from  sprinkler  to 
sprinkler  and  sides  of  room.  Any  stock  piles,  racks  or  other 
obstructions  interfering  with  such  action  are  not  permissible." 

Dry-pipe  and  Alarm  Valves.  —  The  several  different  types 
of  dry-pipe  and  alarm  valves  involve  different  methods  of  test 
and  maintenance.  The  insurance  interests  having  jurisdiction 
will  be  more  than  willing  to  instruct  carefully  any  competent 
person  who  may  be  placed  in  charge  of  these  vital  features. 

Repairs  in  Equipment.  —  The  large  number  of  fires  in 
spririklered  risks  which  have  assumed  serious  proportions  as  the 
direct  result  of  improper  repairs  in  the  sprinkler  system,  points 

*  Rules  of  National  Board  of  Fire  Underwriters. 


MAINTENANCE   OF   FIRE   PROTECTIVE  DEVICES      995 

to  the  absolute  necessity  of  having  such  repairs  made  as  ex- 
peditiously  as  possible,  and  by  thoroughly  competent  mechanics. 
Interruption  to  service,  for  whatever  cause,  constitutes  a  menace, 
hence  the  less  the  service  is  interrupted,  and  the  sooner  it  can 
be  fully  restored,  the  better. 

In  almost  all  cases  the  portion  under  repair  can  be  cut  off 
from  the  rest  of  the  system  by  the  use  of  a  blank  flange  or  cap, 
and  the  protection  as  a  whole  kept  in  service  with  practically  no 
interruption.  ...  Of  the  many  gate- valves  found  closed  by  in- 
spectors, probably  most  of  them  are  due  to  repairs  —  the  engi- 
neer, piper  or  whoever  did  the  work  having  forgotten  to  open 
the  gate.  Frequently  weeks  elapse  before  this  is  discovered.* 

Such  continued  oversight  of  a  closed  valve  could  only  be 
possible,  however,  where  a  particularly  inefficient  or  careless  man 
was  placed  in  charge  of  the  weekly  valve  inspections. 

Changes  in  Premises.  —  The  fire  in  the  building  of  the 
Baldwin  Locomotive  Works  at  Philadelphia  —  briefly  described 
in  Chapter  XXX  —  furnishes  an  excellent  example  of  the  con- 
sequences attendant  upon  careless  or  ill-considered  changes  in 
premises.  A  draughting  room  had  been  partitioned  off  at  one 
end  of  the  third  story,  and,  "in  putting  in  the  ceiling  of  this  room, 
the  sprinklers  had  been  removed  and  not  replaced.  .  .  .  Un- 
fortunately the  water  was  shut  off  from  the  sprinkler  equipment 
nAhe  whole  group,  the  valve  controlling  same  being  closed."  As 
is  not  infrequently  the  case,  the  fire  originated  and  spread  in  the 
one  location  where  sprinkler  protection  had  been  omitted. 

Changes,  re-arrangements  and  additions  to  premises  should, 
therefore,  ^include  equipment  of  a  standard  equal  or  superior  to  the 
balance  of  risk.  If  important  changes  are  contemplated,  such  as 
additional  floors,  the  partitioning  off  of  rooms,  or  extensions  or 
additions,  the  insurance  authorities  should  be  consulted,  and  the 
work  turned  over  to  some  reliable  sprinkler  company. 

Change  in  occupancy  may  also  require  changes  in  the  degree 
of  sensitiveness  of  the  heads  employed. 

Familiarity  with  Apparatus.  —  Fire  protection  and  main- 
tenance should  not  be  made  subservient  to  other  regular  duties. 
Repeated  experience  has  shown  that  the  inspection,  maintenance 
and  general  familiarity  with  fire  protection  apparatus  should  be 
made  a  separate  duty;  and  that  such  duties  should  be  assumed 
only  by  those  fully  competent  to  keep  all  apparatus  in  effective 
*  H.  A.  Fiske. 


996          FIRE    PREVENTION    AND    FIRE   PROTECTION 

operation,  and  competent  to  grasp  intelligently  all  emergencies 
in  case  of  fire. 

Rules  for  Sprinkler  Maintenance.  —  The  following  rules 
regarding  the  care  of  sprinkler  systems  have  been  recommended 
by  the  Underwriters'  Bureau  of  New  England,  as  reducing  the 
chance  of  a  disastrous  fire  to  a  minimum: 

1.  Sprinkler  valves  to  be  kept  open  at  all  times.     Valves  to 
be  strapped  with  leather  straps,  and  to  be  regularly  inspected 
weekly  by  some  responsible  person.      Sprinklers  are  worthless 
if  valve  controlling  them  is  shut. 

2.  In  case  of  fire  have  sprinklers  which  open  replaced  and 
water  turned  on  at  once.     Keep  a  man  stationed  at  sprinkler 
valve  until  it  is  opened. 

3.  Keep  at  least  12  extra  sprinkler  heads  on  hand  at  all 
times.     In  case  you  have  many  high  test  heads  in  your  plant, 
keep  extra  high  test  heads  on  hand  also.     We  suggest  that  these 
be  kept  on  a  rack  or  in  a  glass-front  cupboard  in  engine  room, 
office,  or  other  suitable  place. 

4.  Have  watchman,  engineer,  superintendent,  foreman  and 
others  instructed  as  to  location  of  sprinkler  valves  and  extra 
sprinklers.     Also  to  take  the  following  steps  in  case  of  fire: 
1st.   Call  fire  department  or  other  help.     2nd.   Endeavor  to  ex- 
tinguish fire.     3rd.   When  absolutely  sure  that  fire  is  out,  shut 
off  valve  controlling  sprinklers  that  opened.     4th.    Replace  these 
sprinklers  with  others  of  same  melting-point,  and  turn  on  water 
at  once.     5th.   Sweep  up  water  and  try  to  prevent  unnecessary 
damage. 

5.  Keep  water  supplies  in  service  at  all  times.     Tanks  to  be 
kept  full  and  free  from  ice.     Pumps  to  be  started  weekly,  etc. 

6.  Hire  only  reliable  watchmen  and  engineers.     Many  com- 
panies leave  their  valuable  plant  for  nearly  half  the  time  in  the 
hands  of  ignorant,  low-priced  watchmen  who  are  useless  or  more 
than  useless  in  an  emergency. 

7.  Do  not  build  additions  to  your  plant  without  first  notify- 
ing your  insurance  agent.     Have  sprinkler  equipment  and  other 
fire  appliances  installed  as  soon  as  possible,  and  in  any  event 
before  the  addition  is  used  for  manufacturing  purposes. 

8.  Do  not  build  partitions  or  store  goods  that  will  interfere 
with  sprinkler  distribution. 

9.  Close  cold  weather  valves  November  1st,  and  open  them 
promptly  April  1st. 

10.  Replace  all  sprinkler  heads  that  appear  noticeably  cor- 
roded or  injured  in  any  other  way.     If  in  doubt,  have  a  few  heads 
tested. 

Self-inspection  by  the  Property  Owner  is  recommended  by 
Mr.  Fiske*  to  be  made  as  follows  at  regular  weekly  intervals,  with 
records  of  such  inspection  to  be  kept  on  file  for  reference: 
*  See  Insurance  Engineering,  January,  1907. 


MAINTENANCE    OF   FIRE    PROTECTIVE   DEVICES      997 

• 

Printed  list  of  inside  sprinkler  gate  valves,  each  being  num- 
bered and  having  a  space  to  note  whether  or  not  open  and 
strapped.  Under  this  list  there  should  be  several  blank  lines 
to  note  reasons  for  closed  or  unstrapped  gates,  valves  not  examined, 
drip  pipes  left  partly  open  or  leaking,  etc. 

Similar  list  of  outside  post  gate-valves. 

List  of  all  other  fire  protection  valves,  such  as  those  on 
standpipe  or  at  pump. 

Automatic  sprinklers  —  Condition,  dirty  or  corroded?  Ob- 
structed in  any  way?  Stock  a  sufficient  distance  below  ceiling? 

List  of  pressure  gauges,  with  blank  spaces  to  note  pressures. 

List  of  sprinkler  alarm  cocks  or  valves  controlling  the  alarm, 
open  and  strapped?  When  last  tested,  and  condition? 

List  of  dry- valves,  number  and  location.  Space  to  designate 
whether  air  or  water  is  in  pipes,  and  air  pressure  at  each  valve. 
General  condition  of  valves,  including  latches,  hand-plates,  etc.? 
Leave  a  few  lines  to  note  any  system  that  has  been  flooded  with 
water  since  last  inspection,  and  reason.  Systems  properly 
drained? 

Gravity  Tank.  —  Full  or  not?  Free  from  ice?  Telltale 
in  order?  Condition  of  hoops? 

Pressure  Tank.  —  Water  level  at  proper  point?  Air-pres- 
sure? Glass  gauge  valves  left  closed? 

Steam  Pump  —  Tested  through  relief  valve?  Date  of  last 
thorough  test  with  hose?  All  steam  valves  open  except  at  pump? 
Steam  pressure  at  boilers?  Minimum  pressure  since  last  in- 
spection? Properly  oiled?  Kept  clean?  Automatic  regulator 
in  service,  with  all  steam  valves  wide  open?  Water  pressure 
maintained  at  pump?  Pump  starts  properly  when  pressure  is 
relieved? 

Rotary  Pump  —  Turned  over?  Ample  supply  of  oil?  Date 
of  last  thorough  test  with  hose?  Condition  of  starting  mecha- 
nism? 

Hydrants  —  Free  from  obstructions?  Start  to  open  easily? 
(Hydrants  should  be  opened  and  flushed  Spring  and  Fall,  and 
ordinarily  kept  closed  at  other  times.) 

Hose  —  List  of  hydrant  houses  with  equipment.  Note  that 
everything  is  in  place.  (Hose  should  be  tested  Spring  and  Fall.) 

AUTOMATIC  FIRE  ALARMS. 

In  Boston  all  thermostat ic  systems  and  apparatus  are  in- 
spected once  a  month  by  the  fire  alarm  companies  operating  the 
systems,  and  once  in  every  six  months  in  conjunction  with  the 
Board  of  Fire  Underwriters.  In  some  cases,  notably  in  the  larger 
mercantile  establishments,  monthly  inspections  are  made  by  the 
Board  at  the  request  and  expense  of  the  owners. 

Tests.  —  Systems  of  this  character  are  under  constant  battery 
test,  and  any  disarrangement  will  at  once  be  indicated. 


998         FIRE    PREVENTION    AND    FIRE    PROTECTION 

• 

Maintenance.  —  The  types  of  thermostats  now  generally  em- 
ployed are  not  subject  to  material  depreciation.  Many  have 
given  service  for  as  long  as  fifteen  years  without  showing  de- 
creased sensitiveness. 

Thermostats  should  not  be  painted,  but  kalsomining  is  per- 
missible if  done  with  care. 

STANDPIPES  AND  HOSE  RACKS. 

Standpipes  and  hose  racks,  etc.,  probably  suffer  more  neglect 
than  any  other  important  item  of  protective  equipment,  for  the 
reason  that,  after  once  installed,  they  are  not  usually  looked  upon 
as  requiring  any  particular  care  or  upkeep.  Very  common 
sources  of  trouble,  however,  which  demand  systematic  inspection 
and  maintenance,  include  obstructions,  the  condition  of  valves, 
and  the  condition  of  hose. 

Obstructions  not  infrequently  result  from  building  debris  getting 
into  the  risers  or  Siamese  connections  during  building  operations, 
and  thereafter  blocking  check- valves.  All  openings  in  risers  and 
feed  mains  should  therefore  be  carefully  covered  during  installa- 
tion, and  caps  should  always  be  kept  on  Siamese  connections. 

Valves,  especially,  require  systematic  inspection  to  insure  that 
they  are  in  proper  position,  and  neither  too  tight  nor  too  loose. 

A  story  of  standpipe  neglect  has  lately  been  told  in  insurance 
circles  regarding  a  fire-resisting  building  which  was  provided 
with  a  dry  standpipe  system,  arranged  for  connection  with  fire 
engine  service  at  the  sidewalk  level.  Upon  the  fire  department 
responding  to  an  alarm  of  fire  in  this  building,  connection  was 
at  once  made  from  a  " steamer"  to  the  open  end  of  the  standpipe, 
and  the  engine  started  pumping  to  its  full  capacity.  About  this 
time  the  district  chief  in  charge  shouted  down  from  one  of  the 
upper  floors,  asking  the  firemen  when  they  intended  to  get 
coupled  to  the  standpipe  and  start  operations.  Simultaneously 
a  tenant  of  the  basement  of  the  same  building,  who  had  been 
busy  trying  to  protect  his  stock,  suddenly  appeared  and  shouted 
that  his  quarters  were  being  flooded.  Investigation  showed  that 
an  inside  valve  at  the  lower  end  of  the  standpipe  system  had 
been  left  open,  and  that  the  puffing  fire  engine  was  drowning  out 
the  basement,  while  the  chief  above  was  wondering  why  no 
water  appeared. 

Hose  valves,  because  so  seldom  used,  may  easily  become  so 


MAINTENANCE   OF   FIRE   PROTECTIVE   DEVICES      999 

tight  from  dirt,  rust  or  neglect  that  they  cannot  be  opened  in 
time  of  emergency  save  with  a  wrench.  On  the  other  hand, 
valves  should  not  be  loose  enough  to  permit  leakage,  as  this  will 
contribute  more  to  the  deterioration  of  the  hose  than  any  ether 
cause. 

Care  of  Inside  Hose.  —  Where  hose  is  so  suspended  from  or 
wound  or  folded  upon  a  rack  or  reel  as  to  necessitate  short  bends, 
the  hose  should  be  occasionally  re-folded  so  as  to  prevent  per- 
manent set  or  break  at  the  folds. 

Never  wet  unlined  linen  hose  except  to  use  at  a  fire. 

Keep  the  hose  valves  tight  so  that  hose  will  not  be  wet  by 
leakage. 

Stretch  the  hose  out  or  hang  it  up  at  intervals  so  that  damp- 
ness between  the  folds  or  coils  may  be  dispelled. 

Thoroughly  dry  hose  inside  and  outside  after  it  has  been  wet. 

These  precautions  are  important,  because  linen  hose  is  liable 
to  decay  after  it  is  wet  unless  it  is  at  once  thoroughly  dried. 


AFTER  A  FIRE. 

As  soon  as  possible  put  new  sprinkler  heads  in  place  of  those 
which  have  opened,  and  turn  on  the  water.  Keep  twenty-five 
to  fifty  extra  heads  on  hand  all  the  time  for  this  purpose,  and  for 
mills  having  large  areas  fifty  to  one  hundred  extra  heads  are 
advised. 

Immediately  sweep  out  water,  clean  up  machinery,  save  stock 
and  goods,  dry  out  rooms  with  steam  heat  and  do  exactly  what 
you  would  do  were  there  no  insurance  on  the  property.  Expense 
so  incurred  is  paid  for  by  the  insurance  companies. 

Look  out  for  smoldering  fires.  Remember  that  fire  burrows 
in  raw  cotton  and  may  break  out  hours  or  days  after  the  fire  is 
thought  to  be  extinguished.  Therefore,  with  fires  in  cotton 
storehouses,  picker  rooms,  cotton  bins,  etc.,  understand  that  it  is 
almost  certain  after  fire  once  gets  hold  of  a  lot  of  cotton  that  it 
will  not  be  put  out  until  the  whole  lot  is  turned  over,  a  handful 
at  a  time.  Fires  may  also  smoulder  in  concealed  places  in  floors, 
walls,  partitions,  etc.,  when  there  are  such  faulty  spots. 

When  all  these  things  are  under  way,  notify  the  insurance 
office  through  which  your  insurance  is  distributed,  stating  briefly 
the  cause  and  location  of  the  fire  and  the  probable  loss.  Except 
for  very  small  fires,  it  is  best  to  make  notifications  by  telegraph  or 
telephone. 


CHAPTER  XXXVII. 
FIRE   DRILLS. 

THE  following  regulations  concerning  fire  drills  in  factories, 
schools,  department  stores  and  theatres,  presented  by  Mr.  R.  H. 
Newbern*  before  the  fifteenth  annual  meeting  (1911)  of  the 
National  Fire  Protection  Association,  have  been  adopted  by  that 
Association  as  the  basis  of  its  recommendations  concerning  fire 
drills.  These  regulations  form  the  most  valuable  contribution 
yet  made  to  the  subject,  but  it  is  important  to  bear  in  mind  that 
the  efficiency  of  these  suggestions  is  distinctly  limited  by  the 
question  of  proper  design,  especially  as  regards  means  of  egress, 
as  discussed  in  Chapters  IX  and  XV.f 

Loss  of  Life.  — 

A  recently  published  estimate  places  the  total  annual  loss 
of  life  in  the  United  States  from  fire  causes  at  1500.  In  nine 
disasters  alone  during  the  past  six  years  approximately  1400  per- 
sons have  been  killed  outright  in  addition  to  the  numberless 
maimed  and  injured.  It  is  not  claimed  that  all  of  this  needless 
sacrifice  of  life  could  have  been  wholly  avoided  by  the  simple  ex- 
pedient of  a  fire  drill,  as  in  some  instances  whole  audiences  were 
trapped,  owing  largely  to  inadequate  and  defective  exit  arrange- 
ments. It  is  true,  however,  that  the  absence  of  any  adequate 
provision  for  effective  regulation  and  control  was  an  active  con- 
tributory cause  of  the  panics  which  followed  the  discovery  of  the 
fire. 

Object  of  Fire  Drills.  - 

The  primary  object  of  the  fire  drill  is  to  prevent  panic  con- 
ditions from  arising  by  the  enforcement  of  regular  and  systematic 
practice  in  the  exercise  of  measures  of  restraint  and  self-control. 
In  this  connection  it  is  interesting  to  observe  that  these  results, 
which  are  purely  psychological,  are  achieved  by  a  series  of  evolu- 
tions exclusively  physical  in  character. 

It  is  not  the  purpose  of  this  paper  to  enter  upon  a  discussion 
of  the  requirements  for  fire  escapes,  emergency  exits,  or  of  other 

*  Superintendent  of  Insurance  Department,  Pennsylvania  Railroad  Co. 

t  See  particularly  "Limitation  of  Occupancy,"  page  299, — -"Means  of 
Egress,"  page  300,  —  "Capacity  of  Stairs,"  page  509,  —  "Exterior  Fire  Es- 
capes," page  533,  —  "Safety  of  Employees,"  page  809, — and  "Means  of 
Egress,"  page  811. 

1000 


FIRE   DRILLS  1001 

features  of  construction  and  equipment,  as  the  fire  drill  is  chiefly 
concerned  with  the  determination  of  means '  and  methods  of 
utilizing  to  the  best  advantage  such  facilities  as  are  provided  and 
should  aim  to  adapt  itself  largely  to  existing  conditions.  It  will 
often  be  found,  however,  that  the  institution  of  fire  drill  practice 
will  reveal  conditions  previously  unsuspected  and  point  the  way 
for  re-arranging  and  improving  the  means  of  egress. 

In  order  that  this  paper  might  be  of  some  practical  value  to 
those  having  the  responsibility  for  the  safety  of  life  under  the 
conditions  noted,  an  investigation  was  made  of  conditions  and 
practices  prevailing  in  various  department  stores,  theatres, 
schools  and  factories  for  the  purpose  of  presenting  an  outline  of 
rules  and  instructions  for  the  regulation  and  supervision  of  fire 
drills.  It  was  also  the  intention  to  include  in  the  recommendations 
some  provision  for  drills  in  public  auditoriums  and  churches,  but 
the  difficulties  in  the  way  of  obtaining  the  required  supervision 
in  these  classes  of  risk,  due  to  the  small  number  of  regularly  em- 
ployed attendants  and  the  frequency  with  which  they  are  changed, 
made  this  feature  impracticable;  there  are,  however,  many  of 
the  recommendations  which  will  be  found  adaptable  to  conditions 
in  both  churches  and  public  auditoriums. 

In  devising  a  system  of  fire  drills  the  first  consideration  is  to 
recognize  the  two  classes  of  persons  whom  the  drills  are  to  protect : 
first,  those  who  are  regularly  present  on  the  premises,  such  as 
factory  operatives  or  children  attending  school,  —  secondly,  those 
who  may  be  termed  transients  —  as  the  general  public,  in  de- 
partment stores  and  while  in  attendance  at  churches  or  theatres. 

For  the  first  class  the  problem  is  simplified  by  reason  of  the 
opportunity  afforded  for  regular  training  and  drill  practice  and 
thorough  familiarity  with  all  the  means  of  egress  and  ingress:  so 
that  for  this  class  the  question  is  largely  confined  to  the  character 
and  frequency  of  drills,  to  insure  a  prompt  and  orderly  exit  from 
the  building. 

Those  disasters  which  have  been  most  prolific  in  fatalities 
belong  to  the  second  class,  comprising  those  buildings  where  the 
public  is  assembled  in  considerable  numbers  and  where  congestion 
and  overcrowding  may  be  of  frequent  occurrence.  The  large 
percentage  of  women  and  children  in  these  gatherings  makes  it 
imperative  that  every  possible  safeguard  be  provided  to  insure 
safety  of  life;  and  here  it  may  be  well  to  correct  an  impression 
which  has  become  somewhat  general,  that  in  buildings  of  so-called 
fireproof  construction  the  fire  drill  may  be  considered  unnecessary. 
Recent  investigations  of  conditions  in  connection  with  public 
schools  in  one  of  our  large  cities  developed  the  fact  that  no  pro- 
vision had  been  made  for  fire  drills  where  the  construction  was 
of  a  semi-fireproof  character;  in  two  other  instances  the  absence 
of  fire  drills  was  explained  on  the  grounds  that  the  schools  in 
question  contained  the  more  advanced  grades  and  that  the  pupils 
being  older  and  more  intelligent  did  not  require  the  safeguards  of 
a  fire  drill. 

The  following  suggestions  covering  the  details  of  organiza- 
tion and  ti  aining  for  fire  drills  in  connect  ion  with  factories,  schools, 


1002      FIRE    PREVENTION    AND    FIRE    PROTECTION 

department  stores  and  theatres,  contain  many  of  the  essential 
requirements  for  the  institution  of  fire  drills  in  almost  all  classes 
of  risk,  and  are  herewith  submitted  for  consideration. 


FACTORIES. 

Organization  and  Duties.  — 

All  factory  drills  should  be  subject  to  the  direction  of  a 
supervisory  organization  constituted  as  follows:  chief  of  fire 
drill,  floor  chiefs,  room  captains,  stairway  guards,  and  inspectors. 

Chief  of  Fire  Drill:  Should  be  some  one  whose  position  would 
command  respect  and  insure  compliance  with  all  orders  and  in- 
structions relating  to  fire  drills. 

Duties  of  Chief  of  Fire  Drill:  He  will  have  general  charge  of 
all  matters  pertaining  to  fire  drills,  practice  maneuvers  and  or- 
ganization, and  will  designate  those  persons  to  fill  the  positions 
above  mentioned.  He  will  fix  the  time  for  holding  drills  and 
rigidly  enforce  measures  of  discipline  for  failure  on  the  part  of  any 
employee  to  fully  observe  all  the  rules  and  requirements;  by 
personal  inspection  he  should  see  that  over-crowding  in  work 
rooms  is  prevented  and  that  sufficient  space  is  given  to  aisles  and 
passageways  to  permit  quick  access  in  reaching  all  of  the  exits. 

Floor  Chiefs:  Care  should  be  exercised  in  the  selection  of 
these  men,  as  upon  them  largely  depends  the  efficiency  and  success 
of  the  drill.  Where  department  foremen  or  factory  superin- 
tendents possess  the  requisite  qualifications  their  selection  is  to 
be  preferred.  It  is  important,  however,  that  they  be  men  having 
the  trust  and  confidence  of  their  employees  generally,  with  a 
fair  degree  of  self-possession  and  capable  of  speaking  the  lan- 
guage of  the  operatives. 

Duties  of  Floor  Chiefs:  The  floor  chief  shall  have  immediate 
charge  of  all  operatives  employed  on  his  floor  in  all  matters  per- 
taining to  fire  drills.  He  shall  be  held  responsible  for  the  enforce- 
ment of  all  fire  drill  rules  and  will  reoort  to  the  chief  of  fire  drill 
any  employee  who  wilfully  neglects  their  proper  observance. 

He  shall  see  that  each  movement  corresponding  to  the  alarm 
signal  is  promptly  and  orderly  executed  and  shall  personally 
supervise  the  sounding  of  the  general  building  alarm  on  his  floor. 
He  shall  be  further  responsible  for  the  condition  of  all  aisles  and 
passageways  and  will  see  that  chairs,  benches  and  stock  are 
promptly  removed  to  insure  unobstructed  passage. 

When,  by  pre-arrangement  in  drill  practice  or  as  a  result 
of  actual  fire,  it  may  be  necessary  to  depart  from  the  regular  in- 
structions as  regards  selection  and  use  of  exits,  such  change  will 
be  at  the  sole  direction  of  the  floor  chief. 

Room  Captains:  Whenever  floors  are  subdivided  into  two  or 
more  rooms  the  floor  chief  will  be  assisted  by  the  room  captains. 
For  floors  of  large  area,  the  floor  captains  should  designate  a  drill 
supervisor  for  every  fifty  employees,  to  assist  in  maintaining  the 
necessary  control  and  discipline.  For  these  lat  ter  positions  where 


FIRE    DRILLS  1003 

men  with  the  required  qualifications  are  not  available,  selections 
should  be  made  from  the  forewomen. 

Room  captains  should  be  chosen  from  those  'highest  in 
authority,  preferably  a  foreman  or  work  boss.  The  same  general 
care  in  their  selection  should  be  exercised  as  indicated  for  the 
floor  chiefs. 

Duties  of  Room  Captains:  They  should  perform  the  same 
general  duties  in  their  respective  rooms  as  are  prescribed  for  the 
floor  chief,  subject  to  the  latter's  direction  and  supervision,  ex- 
cepting that  they  shall  have  no  authority  to  change  the  assign- 
ment of  exits,  nor  sound  the  general  building  alarm  unless  under 
direction  of  the  floor  chief.  Where  rooms  are  equipped  with  drill 
gongs  the  room  captains  shall  personally  sound  the  alarm  thereon. 

Stairway  Guards:  For  these  positions  men  are  to  be  pre- 
ferred; they  should  be  strong  and  alert,  capable  of  acting  quickly 
in  emergencies.  Two  men  selected  from  each  floor  should  be 
assigned  to  each  exit  or  stairway. 

Duties  of  Guards:  Guards  are  to  be  subject  to  the  orders  of 
the  floor  chief  or  room  captains  and  shall  see  that  the  march  from 
the  rooms  and  in  descending  the  stairway  is  orderly  and  without 
crowding  and  at  uniform  speed,  with  careful  observance  of  spacing 
between  files.  They  shall  be  especially  watchful  of  persons 
stumbling  or  falling  to  prevent  trampling  and  shall  be  given 
authority  to  halt  the  line  when  conditions  require. 

Guards  shall  be  stationed  as  follows :  One  guard  on  the  stair 
side  of  the  door  leading  from  the  room  and  one  guard  midway  on 
staircase  descending  to  the  next  floor  below.  Where  stair  exits 
have  sharp  bends  or  are  poorly  lighted  additional  guards  should 
be  provided  as  required. 

On  fire  escapes  where  conditions  permit,  the  arrangement 
will  be  similar  to  that  outlined  for  stairways,  with  the  exception 
that  the  guards  shall  be  stationed  on  the  balconies  or  platforms 
instead  of  midway  between  the  floors.  In  this  connection  it  is 
believed  that  when  inclined  ladders  are  used  for  fire  escapes, 
provision  should  be  made  for  erecting  a  small  swinging  platform 
enclosed  by  a  guard  rail,  in  order  to  permit  the  stationing  of  guards 
at  advantageous  points. 

Inspectors:  An  inspector  selected  from  among  the  operatives 
should  be  appointed  to  examine  each  morning  the  condition  of  all 
stairways,  fire  escapes  and  roof  exits,  if  any,  and  to  report  im- 
mediately to  the  chief  of  fire  drill  any  obstruction  found  thereon 
or  any  other  unusual  condition.  He  shall  also  see  that  all  doors 
leading  t6  stairways  or  exits  open  outwardly  and  will  immediately 
report  any  found  locked  or  obstructed  to  the  floor  chief  or  chief 
of  fire  drill. 

During  the  winter  season  attention  should  be  given  fire 
escapes  where  exposed  to  accumulations  of  ice  or  snow  and,  when- 
ever found,  immediate  steps  should  be  taken  for  its  prompt 
removal. 

In  addition  to  the  above,  provision  should  be  made  for  a  daily 
inspection  each  morning  of  the  alarm  system  and  of  all  signaling 
devices;  report  thereof  to  be  made  to  the  chief  of  fire  drill. 


1004      FIRE   PREVENTION   AND   FIRE   PROTECTION 

Drill  Exercise.  — 

Fire  drills  should  be  held  weekly  without  notice,  at  different 
hours,  and  should  include  all  employees  in  the  building. 

It  is  advisable  that  the  alarms  announcing  the  drills  for  each 
trial  should  originate  on  different  floors,  in  order  to  afford  practice 
in  changing  the  order  of  precedence  for  possession  of  stairways 
or  fire  escapes;  excepting  that  drill  evolutions  may  be  so  ar- 
ranged to  take  advantage  of  the  additional  time  required  in  the 
descent  of  those  from  the  upper  floors,  by  dismissing  such  of  the 
lower  floors  as  would  not  delay  the  egress  of  the  former. 

A  further  exception  to  the  rule  should  be  made  where  build- 
ings are  divided  by  fire  walls  having  protected  openings,  which 
would  allow  the  transfer  of  all  the  occupants  on  a  given  floor  in 
the  fire  section  to  an  adjoining  section  on  the  same  floor,  or  where 
provision  is  made  for  ascending  to  roof  exits  that  may  lead  to  a 
safe  retreat,  either  on  or  in  an  adjoining  building. 

Drill  practice  should  closely  approximate  military  precision. 
All  drill  movements  should  lead  in  the  direction  of  the  exits  and 
follow  in  response  to  gong  strokes. 

The  first  alarm  will  consist  of  a  series  of  strokes  on  a  large 
gong  (once  repeated),  indicating  the  floor  from  which  the  alarm 
is  given.  Upon  the  first  stroke  of  this  alarm  all  operatives  will 
immediately  cease  work,  rise  and  as  far  as  possible  shut  off  power 
to  machines.  Thereafter  each  succeeding  movement  will  be 
announced  by  single  strokes  on  the  smaller  drill  gongs,  sounded 
by  the  floor  chief  or  room  captain. 

Upon  the  first  stroke  of  the  drill  gong  each  operative  will 
remove  the  stock,  chairs  or  benches  nearest  him  in  the  aisles, 
placing  same  either  under  or  on  top  of  the  work  table  or  machine. 
Before  the  sounding  of  the  second  stroke  all  aisles  and  passage^ 
ways  should  be  cleared  of  obstructions  and  operatives  ready  for 
line  formation,  which  should  be  announced  by  the  second  stroke. 
Line  formation  will  consist  of  files  of  two,  using  free  hand  to  raise 
the  skirt  to  prevent  tripping  those  in  the  immediate  rear. 

The  third  stroke  will  be  the  signal  to  march  to  the  door  of 
exit  passage,  and  each  file  will  move  forward,  observing  a  uniform 
distance  between  to  prevent  touching.  The  line  should  halt  at 
doorway  on  an  arm  motion  signal  of  either  the  floor  chief  or  room 
captain,  otherwise  to  continue  on  to  the  stairway  and  descend, 
being  subject  only  to  the  signals  of  the  stairway  guards. 

Drill  exercises  should  aim  to  bring  into  practice  as  often  as 
possible  all  of  the  signals  as  mentioned,  to  insure  against  possible 
misunderstanding  at  a  critical  time. 

Upon  reaching  the  street  the  line  should  be  led  away  to  a  safe 
distance  to  prevent  crowding  and  confusion  around  the  exit,  and 
for  this  purpose  one  of  the  room  chiefs  or  drill  supervisors  from 
the  first  or  nearest  street  floor  should  be  assigned  to  the  duty  of 
leading  the  line  away  from  the  building. 

It  is  urged,  as  often  as  conditions  will  permit,  that  all  em- 
ployees at  the  close  of  business  be  dismissed  through  the  drill 
exits. 


FIRE    DRILLS  1005 

Note  "A"  -  -  The  practice  of  holding  separate  fire  drills  for 
each  room  or  department  of  a  building,  unless  in  sections  cut  off 
by  standard  fire  walls,  is  believed  to  be  a  serious  mistake,  not 
alone  for  the  single  tenant  factory  but  in  particular  for  the  omni- 
bus tenant  where  jurisdiction  over  employees  is  divided  and 
where  operatives  of  two  or  more  separate  employers  are  required 
to  use  the  same  avenues  of  egress  and  ingress.  For  fire  drill  pur- 
poses, every  omnibus  factory  building  should  be  considered  as 
a  unit  and  the  suggestions  and  recommendations  herein  made 
applied  to  the  building  as  a  whole. 

Elevator  attendants  should  be  instructed  to  take  cars  im- 
mediately upon  the  first  round  of  the  building  alarm  to  the  floor 
indicated  and  hold  themselves  subject  to  the  orders  of  the  floor 
chief. 

Assignment  of  Exits.  — 

The  assignment  of  exits  will  depend  primarily  upon  their 
number,  capacity  and  location  and  to  some  extent  on  their 
arrangement.  Exits  discharging  horizontally  into  another  build- 
ing or  into  another  section  of  the  same  building  which  is  cut  off 
by  a  fire  wall  having  standard  protected  openings  will  accom- 
modate a  considerably  greater  number  than  the  stair  or  regular 
fire  escape  exits  and  with  the  possibilities  of  danger  reduced. 

In  assigning  exits  where  the  capacity  of  the  fire  escapes  is 
limited,  the  occupants  of  lower  floors  should  be  required  to  use 
the  inside  stairways  in  order  to  reserve  the  fire  escapes  for  the 
use  of  the  upper  floors. 

Where  conditions  permit,  it  would  be  desirable  in  drills  to 
use  the  regular  entrances  for  exit  purposes  on  account  of  their 
familiarity  to  the  employees  constantly  using  them.  In  their 
selection,  however,  consideration  should  be  given  to  possible  ex- 
posure by  local  hazards,  such  as  proximity  to  heating  and  power 
plants  and  any  hazardous  processes  connected  with  the  working 
of  the  factory  product.  It  is  also  important  in  arranging  the 
fire  drill  exits  to  allow  one  or  more,  if  possible,  as  entrances  for 
firemen.  The  assignment  of  exits  for  different  floors  should  first 
be  based  on  approximate  estimates  of  their  relative  discharging 
capacities,  then,  as  a  result  of  actual  tests  based  on  these  estimates, 
the  distribution  to  each  exit  can  be  revised  so  that  the  time  con- 
sumed will  average  about  the  same  for  all.  In  these  trials  every 
available  exit,  including  those  reached  by  way  of  the  roof,  should 
be  considered. 

Frequently  the  arrangement  of  exits  may  be  such  as  to  per- 
mit a  safer  and  more  rapid  dismissal  from  an  upper  floor  by  using 
the  regular  exits  to  one  of  the  lower  floors  in  order  to  reach  an 
exit  discharging  on  another  side  of  the  building.  Combinations 
of  this  kind  should  be  utilized  wherever  possible. 

Notification.  - 

For  the  purpose  of  sounding  a  general  building  alarm,  each 
factory  building  should  be  equipped  with  an  electrically  operated 
alarm  system  of  the  closed  circuit  type  on  gravity  batteries. 


1006      FIRE   PREVENTION    AND   FIRE   PROTECTION 

Connected  in  circuit  with  this  system  there  should  be  one  or  more 
electro-mechanical  gongs  on  each  floor  of  suitable  size  to  insure 
being  heard  above  the  noise  of  moving  machinery.  The  gongs 
on  each  floor  should  simultaneously  indicate  by  strokes  the  floor 
from  which  the  alarm  is  given,  which  should  be  once  repeated. 

The  use  of  the  box  stations  should  be  restricted  as  far  as 
possible,  in  order  to  confine  their  use  to  the  floor  chief  or  his 
assistants,  as  conditions  may  require. 

Independent  of  the  general  building  alarm  system,  there 
should  be  provided  on  each  floor,  or  when  necessary,  in  each 
room,  a  separate  gong  for  drill  purposes.  The  gongs  to  be  placed 
near  or  within  convenient  reach  of  the  floor  chief  or  room  captain 
and  to  be  provided  with  hand  pulls.  These  gongs  will  announce 
all  drill  movements  following  the  sounding  of  the  general  building 
alarm,  as  indicated  in  the  instructions  covering  "  Drill  Exercise." 

All  alarm  gongs  used  as  fire  drill  signals  should  be  distinctive 
in  tone  and  not  used  for  other  than  drill  purposes. 

For  the  information  of  all  employees,  notices  should  be 
posted  in  each  room  giving  full  instructions  in  all  matters  per- 
taining to  fire  drills.  These  notices  should  be  printed  in  the 
respective  languages  of  the  operatives. 

The  engineer  in  every  factory,  upon  the  first  signal  of  the 
building  alarm,  should  be  instructed  to  shut  off  all  power  to 
machines  and  shafting  throughout  the  building,  excepting  in  cases 
where  it  would  affect  the  operation  of  the  fire  pumps,  elevators  or 
the  lighting  system. 

SCHOOLS. 

Organization.  — 

Fire  drill  supervision  to  be  effective  for  public  schools  should 
be  simple  and  direct.  This  can  best  be  obtained  by  adapting 
the  school  organization,  through  its  teaching  staff,  to  the  require- 
ments of  the  fire  drill. 

Principal:  The  principal  should  be  supreme;  he  should  fix 
the  time  for  the  holding  of  drills  and  preserve  a  record  thereof, 
showing  the  time  required  to  effect  the  dismissal  of  the  entire 
school,  and  enforce  measures  of  discipline  for  failure  of  any 
teacher  or  pupil  to  fully  observe  all  the  rules  and  requirements. 
He  should  designate  as  assistants  one  teacher  on  each  floor  who, 
subject  to  his  authority,  shall  have  general  direction  of  drill  exer- 
cises. Upon  these  assistants  will  devolve  the  important  duty  of 
changing  the  assignment  of  exits,  when,  either  by  ^rearrangement 
in  drill  practice  or  as  a  result  of  actual  fire  conditions,  it  may  be 
necessary  to  depart  from  the  regular  assignments.  The  assistants 
should  be  authorized  to  sound  alarms  and  instructed  in  the 
method  of  operating  the  alarm  boxes. 

Teachers:  Each  class  will  be  under  the  immediate  direction 
of  its  teacher,  upon  whom  will  largely  depend  the  efficiency  and 
success  of  the  drill. 

The  degree  of  efficiency  attained  in  school  drills  will  depend 


FIRE   DRILLS  1007 

largely  on  the  character  of  the  discipline  maintained  by  the 
teachers,  and  any  departure  from  the  strict  letter  of  the  rules 
should  be  followed  immediately  by  proper  measures  of  discipline, 
as  a  single  act  of  untimely  disobedience  to  the  rules  might  at  a 
critical  time  threaten  the  safety  of  the  entire  school.  ' 

Janitor:  Under  direction  of  the  principal,  the  school  janitor 
should  be  required  to  perform  daily  the  following  duties:  to  in- 
spect all  fire  escapes  and  stairways  immediately  after  the  assem- 
bling of  the  school  at  each  session,  and  to  remove  therefrom  any 
obstruction  and  to  keep  fire  escapes  free  of  accumulations  of 
ice  and  snow;  to  examine  all  doors  of  class  rooms,  including  the 
main  exits,  to  see  that  they  open  outwardly  and  are  kept  un- 
locked and  ready  for  instant  opening;  and  where  windows  are 
used  as  exits  to  fire  escapes,  he  should  likewise  see  that  all  bolts 
and  fastenings  are  drawn  and  open.  In  addition  to  this  work  he 
should  be  required  to  perform  fire  patrol  duty  by  making  com- 
plete tours  of  the  building  hourly  and  registering  on  an  approved 
watchman's  clock. 

In  schools  where  electric  alarm  systems  are  installed  he  shall 
make  a  daily  test  of  the  system,  selecting  for  each  trial  a  different 
box;  report  thereof  to  be  made  to  the  principal. 

Drill  Exercise.  - 

Fire  drills  should  be  held  weekly  at  different  hours  while  the 
classes  are  engaged  in  their  regular  exercises  and  also  when 
assembled  in  the  auditorium,  without  notice  to  either  teachers  or 
pupils.  Drills  should  include  all  persons  within  the  building. 
They  should  be  orderly  and  without  confusion  and  be  conducted 
with  military  precision.  There  should  be  no  unnecessary  move- 
ments and  each  movement  should  lead  in  the  direction  of  the  exit 
and  follow  in  response  to  a  bell  signal. 

The  first  signal  will  consist  of  a  series  of  strokes  on  the  large 
gongs  connected  with  the  general  school  alarm,  which  will 
indicate  by  strokes  the  number  of  the  box;  this  signal  will  be  once 
repeated.  At  the  first  stroke  of  this  alarm,  pupils  will  cease  work 
and  be  at  attention.  Thereafter  each  succeeding  movement  will 
follow  bell  signal  on  the  tap  bell  at  the  teacher's  desk. 

Upon  the  first  signal  of  the  tap  bell,  pupils  will  rise,  and  re- 
main standing  in  the  aisles  beside  their  desks.  At  the  second 
signal  they  will  move  forward  into  double  lines  two  abreast,  the 
heads  of  the  lines  halting  at  the  exits  until  signalled  to  march 
by  the  teacher.  After  assurance  that  the  stairway  approaches 
are  clear  of  the  other,  classes  who  may  have  precedence,  the 
teacher  should  remain  stationed  at  the  exit  from  the  class  room 
until  half  or  two-thirds  of  the  pupils  are  out.  To  avoid  confusion, 
the  precedence  of  each  class  should  be  determined  in  advance  and 
care  exercised  to  prevent  the  lines  of  two  or  more  classes  crossing 
in  reaching  the  exits.  In  order  to  obtain  proper  supervision  of 
the  line  while  descending  stairways,  one  or  more  of  the  teachers 
on  the  lowest  floor  should  remain  stationed  between  the  foot  of 
stairway  and  the  main  exit  until  all  of  the  classes  have  passed  out. 


1008      FIRE   PREVENTION   AND   FIRE   PROTECTION 

The  other  teachers  from  the  upper  floors  should  take  up  positions 
on  the  stairways  at  short  intervals,  remaining  there  until  the  end 
of  the  line  has  passed. 

No  pupil  should  be  permitted  to  leave  the  line  to  secure  hat, 
coat  or  other  apparel,  nor  for  any  other  purpose  whatever. 
Teachers  should  see  that  the  movement  of  the  line  is  at  uniform 
speed  and  that  the  regular  spacing  between  files  is  carefully  ob- 
served to  prevent  touching. 

For  fire  escapes  the  same  general  arrangement  should  be 
followed,  excepting  that  the  teachers  should  remain  on  the  bal- 
conies, not  more  than  one  teacher  to  each  balcony. 

Two  teachers  from  the  lowest  floor  should  be  assigned  to  lead 
the  line  away  from  the  building  and  an  additional  teacher  sta- 
tioned at  the  gate  entrance  to  the  school  yard  and  outside  the 
main  building  exit. 

In  order  to  allow  for  possible  fire  conditions  which  might  cut 
off  the  exit  assigned  to  a  particular  floor  or  class,  it  is  advisable 
that  the  alarms  for  each  drill  should  originate  on  different  floors 
to  afford  practice  in  changing  the  regular  assignment  of  exits. 
It  is  also  urged,  in  order  to  meet  possible  contingencies,  that  drills 
be  held  while  the  school  is  assembled  in  whole  or  in  part  and 
during  recess  periods.  The  practice  of  occasionally  dismissing 
the  school  through  the  fire  exits  at  the  close  of  the  session  is  also 
recommended. 

In  schools  of  the  more  advanced  grades,  it  will  be  possible  to 
organize  a  fire  brigade  from  among  the  pupils  for  handling  chemi- 
cal extinguishers  and  hose  streams  from  standpipes.  For  this 
work  some  of  the  stronger  boys  should  be  selected  from  each  class 
and  regularly  drilled  under  direction  of  the  janitor.  But  in  no 
case  should  this  work  interfere  with  the  dismissal  of  the  school 
by  means  of  the  fire  drill.  Where  pianos  or  other  instruments 
are  available  the  use  of  march  time  music  is  recommended  during 
drills. 

Assignment  of  Exits.  — 

In  assigning  exits  where  the  capacity  of  the  fire  escapes  is 
limited,  the  lower  floors  should  be  required  to  use  the  inside 
stairway  in  order  to  reserve  the  fire  escapes  for  the  use  of  the 
upper  floors.  Care  should  be  taken  in  the  selection  of  stairways 
to  avoid  the  use  of  any  exposed  by  stair  entrances  to  cellars  con- 
taining the  school  heating  plant. 

For  classes  of  the  smaller  children  in  the  kindergarten  and 
primary  grades,  preference  should  be  given  in  the  assignment  of 
exits  to  insure  their  safety.  For  these  grades,  when  located  above 
the  street  floor,  it  is  particularly  urgent  that  exits  should  be  pro- 
vided by  means  of  independent  fireproof  towers. 

All  stairways  five  feet  or  more  in  width  should  accommodate 
double  lines  of  two  each  and  will  therefore  allow  of  the  movement 
of  two  classes  simultaneously;  all  stairways  so  used  should  be 
provided  with  ti  center  hand  rail. 

Other  exits  than  those  regularly  assigned  to  each  class  or 


FIRE    DRILLS  1009 

floor  should  be  designated  in  order  that  the  classes  may  be  quickly 
shifted  to  exits  in  another  part  of  the  building.  These  changes 
should  only  be  made  at  the  direction  of  the  assistant  in  charge 
of  the  floor. 

Where  exits  can  be  arranged  to  discharge  horizontally,  they 
are  to  be  preferred.  This  may  be  clone  where  buildings  are 
divided  into  two  or  more  sections,  cut  off  by  fire  walls  having 
standard  protected  openings.  It  will  also  be  possible  in  buildings 
of  this  class  to  provide  exits  through  the  roof  by  which  pupils 
may  reach  the  roof  of  an  adjoining  section  and  descend  to  the 
street. 

Where  the  exit  arrangements  permit,  a  safer  and  more 
prompt  dismissal  can  sometimes  be  effected  for  the  upper  floors 
by  using  the  regular  exits  to  a  lower  floor  and  re-entering  the 
building  in  order  to  reach  an  exit  discharging  on  another  side. 
Provision  for  this  arrangement  should  be  made  in  the  regular  drill 


Notification.  - 

For  the  purpose  of  sounding  the  general  alarm,  each  school 
should  be  equipped  with  an  electrically  operated  alarm  system  of 
the  closed  circuit  type  on  gravity  batteries;  connected  in  circuit 
with  the  system,  there  should  be  installed  on  each  floor  of  the 
building  one  or  more  electro-mechanical  gongs  of  suitable  size 
to  insure  being  heard  in  each  class  room. 

The  gongs  should  be  arranged  to  strike  simultaneously 
throughout  the  building,  indicating  by  strokes  the  number  of 
the  box  pulled. 

In  buildings  having  5000  square  feet  or  more  of  floor  area 
there  should  be  four  boxes  on  each  floor,  placed  immediately  out- 
side the  entrance  to  each  of  the  corner  class  rooms.  Box  numbers 
should  be  chosen  somewhat  as  follows: 

First  Floor  —  Numbers 11  to  14  inclusive 

Second    " 21  to  24 

Third      " 31  to  34 

Fourth    " 41  to  44 

Fifth        " 51  to  54 

The  alarm  from  each  box  to  sound  two  rounds.       . 

In  addition  to  the  general  school  alarm  system,  each  class 
room  should  be  provided  with  a  small  tap  bell  to  be  used  by  the 
teacher  in  announcing  drill  movements  following  the  box  alarm. 

Note.  —  No  general  alarm  for  fire  drill  in  any  school  building 
should  be  sounded  on  a  gong  used  for  other  than  fire  purpose. 
The  practice  of  using  fire  alarm  gongs  for  announcing  class  periods 
is  to  be  condemned. 

An  auxiliary  fire  alarm  box,  connected  with  the  public  fire 
alarm  system,  should  be  installed  in  each  school  near  the  main 
entrance,  and  the  sounding  of  the  alarm  should  be  the  duty  of  the 
janitor. 

There  should  be  displayed  in  each  class  room  a  card  of  in- 


1010      FIRE    PREVENTION    AND    FIRE    PROTECTION 

structions  containing  all  rules  and  requirements  pertaining  to  the 
fire  drill. 

The  observance  of  regular  fire  drill  practice  should  be  re- 
quired in  every  public  school  without  regard  to  age  or  advanced 
standing  of  its  pupils,  and  no  school  should  be  exempt  by  reason 
of  the  fireproof  character  of  its  structure,  however  superior. 
Experience  has  shown  that  the  occurrence  of  panic  is  not  confined 
to  any  particular  kind  of  building,  and  that  adults  are  often  as 
susceptible  to  its  influences  as  are  children. 

DEPARTMENT  STORES. 

Object  of  Drill.  - 

The  primary  object  of  the  fire  drill  for  the  department  store 
should  be  to  afford  training  and  instruction  for  its  employees  in 
the  handling  and  control  of  the  public  under  conditions  of  panic. 
This  must  be  accomplished  largely  by  individual  instruction  and 
occasionally  by  execution  of  drill  maneuvers,  after  the  close  of 
business  when  the  public  is  absent.  It  is  recognized  as  a  serious 
handicap  that  these  drills  must  be  conducted  with  no  opportunity 
for  testing  their  working  efficiency  under  conditions  approxi- 
mating actual  service,  and  for  this  reason  they  should  be  given  the 
closest  supervision  to  insure  the  trained  cooperation  of  every 
employee.  As  a  large  percentage  of  employees  in  department 
stores  may  consist  of  women  and  girls,  their  active  participation 
in  the  general  fire  drill  work  would  not  as  a  rule  be  desirable. 
They,  however,  should  be  instructed  and  drilled  in  the  taking  of 
prompt  measures  for  their  own  safety,  which  if  properly  done  may 
by  its  influence  and  example  materially  assist  in  the  handling  of 
the  general  public. 

Organization  and  Duties.  — 

For  department  stores  the  fire  drill  organization  should  be 
constituted  as  follows:  chief  of  fire  drill,  assistant  chief  of  fire 
drill,  floor  chiefs,  captains,  guards  and  inspectors,  in  addition  to 
all  of  the  male  employees  over  18  years  of  age. 

Duties  and  assignments  to  be  as  follows: 

Chief  of  fire  drill:  He  should  be  some  one  prominent  in  the 
administration  of  the  store,  whose  position  would  command  re- 
spect and  insure  compliance  with  all  orders  and  instructions  re- 
lating to  the  fire  drill. 

Duties  of  chief  of  fire  drill:  He  will  have  general  charge  of  all 
matters  pertaining  to  fire  drill  instructions,  practice,  maneuvers 
and  organization  and  will  designate  those  persons  to  fill  the  posi- 
tions above  mentioned.  He  will  fix  the  time  for  holding  drills 
and  rigidly  enforce  measures  of  discipline  for  failure  on  the  part 
of  any  employee  to  fully  observe  all  the  rules  and  requirements. 

Assistant  chief  of  fire  drill:  For  this  position  either  the  build- 
ing superintendent  or  his  assistant  should  be  selected. 

Duties  of  assistant  chief  of  fire  drill:  He  will  assist  the  chief  in 
all  matters  pertaining  to  fire  drill,  performing  such  other  duties 


FIRE    DRILLS  1011 

as  are  assigned  him  by  the  chief  and  perform  the  latter's  duties 
in  his  absence. 

Floor  chief:  Should  be  either  a  head  of  department  or  the 
chief  aisle  manager. 

Duties  of  floor  chief:  The  floor  chief  shall  have  immediate 
charge  of  all  employees  on  his  floor  in  all  matters  pertaining  to 
fire  drills.  He  shall  see  that  employees  receive  proper  instruc- 
tions, and  will  be  held  responsible  for  the  enforcement  of  all  rules 
relating  to  fire  drill  work,  and  will  immediately  report  to  the  chief 
any  employee  who  wilfully  neglects  their  observance.  He  will  be 
responsible  for  the  maintenance  of  necessary  aisles  and  passage- 
ways leading  to  all  exits  and  will  see  that  all  doors  leading  thereto 
are  hung  to  open  outward. 

During  drill  practice  he  should  have  general  direction  of 
maneuvers  on  his  floor  and  will  see  that  each  movement  is 
promptly  and  orderly  executed. 

Captain:  For  this  position  the  head  of  each  department  or 
his  assistant  should  be  selected;  when  the  head  of  the  department 
is  chosen,  the  assistant  should  be  fully  instructed  in  all  the  duties 
of  his  superior  pertaining  to  fire  drill. 

Duties  of  captain:  He  should  perform  the  same  general  duties 
in  his  particular  department  as  are  prescribed  for  the  floor  chief, 
subject  to  the  latter's  supervision  and  direction. 

Guards:  For  this  position  strong,  alert  men  should  be  se- 
lected, capable  of  acting  quickly  in  emergencies. 

Duties  of  guards:  One  guard  to  be  stationed  on  each  side, 
at  foot  of  stairway  descending  from  the  floor  above,  when  stair- 
ways are  not  continuous,  and  one  guard  stationed  on  each  side  at 
head  of  stairway  leading  to  floor  below  and  one  guard  on  each 
side  of  stair  landing  intermediate  between  the  two  floors.  Where 
stairways  have  more  than  one  bend  or  landing  two  additional 
guards  should  be  assigned  to  each. 

Guards  as  far  as  possible  will  regulate  the  movement  of  the 
lines  on  the  stairways  and  will  be  especially  watchful  of  persons 
stumbling  or  falling. 

In  stair  towers  or  on  fire  escapes  where  conditions  permit, 
the  arrangement  will  be  similar  to  that  outlined  for  stairways, 
with  the  exception  that  no  guards  should  be  stationed  on  the 
stairways  between  the  floors  unless  at  landings  or  on  balconies. 

Inspectors:  One  or  more  uniformed  inspectors,  preferably 
with  fire  department  experience,  should  be  employed  for  day  fire 
patrol  duty,  who  shall  make  regular  rounds  of  the  building  and 
register  on  an  approved  watchman's  clock.  The  rounds  should 
cover  all  fire  escapes,  stairway  exits,  doors  and  windows,  where 
the  latter  are  used  as  exits  to  fire  escapes  or  stair  towers.  He 
should  report  immediately  to  the  building  superintendent  and 
chief  of  fire  drill  any  obstructions  found  on  the  fire  escapes,  or 
any  other  unusual  conditions,  and  during  the  winter  season  should 
give  particular  attention  to  fire  escapes  exposed  to  accumulations 
of  ice  or  snow.  Doors  or  windows  used  as  exits  to  stairways  or 
fire  escapes  when  found  locked  should  be  promptly  reported  to 
building  superintendent  and  chief  of  fire  drill.  In  addition  to 


1012      FIRE    PREVENTION    AND    FIRE    PROTECTION 

these  duties  the  inspector  shall  make  a  daily  test  of  the  signaling 
system. 

For  the  large  city  department  stores  of  more  than  20,000 
square  feet  ground  area  it  would  seem  advisable  to  have  an  in- 
spector for  each  floor. 

Companies:  The  fire  drill  organization  will  include  all  male 
employees  over  18  years  of  age,  excepting  such  as  may  be  assigned 
to  fire  brigade  duty.  The  employees  in  each  department  or  fire 
district  will  be  organized  into  separate  companies  under  the 
direction  of  the  department  manager  or  the  assistant  manager 
having  the  title  of  captain. 

These  companies  will  be  assigned  to  duty  in  the  aisles  as 
hereinafter  provided  for: 

Drill  Exercise.  — 

For  fire  drill  purposes,  each  floor  should  be  divided  into  fire 
districts  with  as  many  districts  as  there  are  departments,  except- 
ing that  the  total  floor  area  of  each  district  should  not  exceed 
7500  square  feet,  preferably  5000  square  feet.  Special  provision 
may  be  made  for  those  departments  where  the  nature  of  the  stock 
requires  large  floor  space  and  where  there  is  less  congestion  of 
both  patrons  and  employees,  which  would  apply  to  stocks  of 
furniture,  carpets,  pianos,  etc. 

Fire  drills  for  instruction  should  be  held  fortnightly,  either 
before  or  after  regular  business  hours.  They  should  be  orderly 
and  without  confusion  and  conducted  with  marked  precision,  and 
the  movements  should  be  simple  and  as  few  in  number  as  possible. 

Upon  the  first  signal  of  the  alarm,  each  member  of  the  fire 
drill  company  in  the  district  in  which  the  alarm  is  sounded  will 
immediately  cease  work  and  proceed  to  remove  obstructions  from 
the  aisles  and  passageways.  They  should  then  form  in  double 
lines  along  each  side  of  the  aisle  leading  to  the  exit,  taking  up 
stations  at  proper  intervals  and  wherever  possible  at  the  junction 
of  intersecting  aisles.  In  assigning  stations,  the  first  considera- 
tion is  to  man  the  main  aisles  leading  to  each  exit  from  the  fire 
district  and  to  prevent  pushing  and  overcrowding.  As  far  as 
possible,  the  aisle  guards  will  endeavor  to  effect  line  formation, 
in  order  that  the  approach  to  the  exit  may  be  as  orderly  as  pos- 
sible. At  all  times  special  consideration  should  be  given  women 
and  children. 

The  stair  and  exit  guards  should  in  like  manner  endeavor  to 
keep  the  lines  intact  and  to  act  quickly  in  cases  where  persons 
may  stumble  or  fall,  to  prevent  trampling. 

In  the  organization  of  each  company  there  should  be  desig- 
nated not  less  than  four  of  its  members  to  lead  the  lines  in  descend- 
ing stairways  and  tower  exits  to  the  street  floor. 

Upon  the  sounding  of  an  alarm  in  any  fire  district,  the  fire 
drill  company  in  the  two  nearest  districts  should  assemble  and 
stand  ready  to  render  any  assistance  required.  These  com- 
panies may  be  used  to  advantage  where  the  regular  exits  for  the 
section  where  the  alarm  is  sounded  are  exposed  or  cut  off  by  the 


FIRE    DRILLS  1013 

fire,  by  assisting  in  the  formation  of  lines  and  leading  them  to 
other  nearby  exits. 

When  stores  are  divided  into  sections  cut  off  by  fire  walls 
with  standard  openings,  the  drill  exercises  should  be  directed  to 
their  use  in  preference  to  stairways  and  fire  escapes. 

Women  and  girl  employees  and  boys  who  are  not  members 
of  the  fire  drill  of  the  section  in  which  the  alarm  is  sounded,  upon 
the  first  signal  should  be  at  attention  and  assemble  for  line  forma- 
tion. The  lines  should  consist  of  files  of  two  each,  using  a  free 
hand  for  raising  skirts.  Upon  the  second  fire  signal  the  line 
should  move  promptly  and  orderly  at  uniform  speed,  to  prevent 
the  touching  of  any  two  files.  One  of  the  older  girls  or  women 
should  be  designated  in  each  department  to  lead  the  line  to  the 
exits. 

When  fire  conditions  permit,  the  line  should  be  led  off  to 
other  exits  than  those  to  which  the  public  may  be  crowding;  no 
employee  should  attempt  to  secure  clothing  or  street  apparel  from 
locker  or  cloak  rooms. 

Assignment  of  Exits.  — 

Under  conditions  existing  in  department  stores,  no  regular 
assignment  of  exits  for  departments  can  be  made  that  would  be 
recognized  by  the  public.  Floor  managers  should  designate  cer- 
tain fire  exits  for  each  department  and  as  far  as  possible  the  drill 
company  should  direct  the  public  to  these  exits.  With  ordinary 
fire  supervision  it  is  improbable  that  any  fire  in  a  modern  depart- 
ment store  will  expose  more  than  a  single  floor  or  section  of  the 
building,  and  under  ordinary  circumstances  there  would  be  no 
advantage  in  forcing  the  public  to  the  use  of  any  one  exit,  if 
others  equally  safe  were  available. 

When  exits  can  be  arranged  to  discharge  horizontally  they 
are  to  be  preferred.  This  may  be  done  when  buildings  are  divided 
into  two  or  more  sections,  cut  off  by  fire  walls  having  standard 
protected  openings. 

It  will  also  be  possible  in  buildings  of  this  class  to  provide 
exits  through  the  roof  by  which  egress  may  be  had  to  an  adjoining 
section. 

Signs  indicating  location  of  all  stairways,  fire  escapes  and 
other  exits  should  be  displayed  in  the  main  aisles  throughout  the 
building.  For  this  purpose  it  is  believed  that  the  hollow  iron 
sign  with  the  letters  cut  in  each  side,  against  a  white  background, 
are  the  most  effective.  These  signs  may  be  illuminated  for  use 
in  any  dark  sections  of  the  building. 

Elevator  attendants  will  remain  at  their  posts  of  duty  and 
continue  to  carry  passengers  until  notified  by  the  floor  chief  or 
captain.  If  the  fire  should  expose  the  elevator  shaft,  attendants 
are  not  to  attempt  to  run  their  cars. 

Notification.  — 

The  fire  alarm  should  be  distinctive,  but  of  a  type  not  likely 
to  be  recognized  by  the  public;  for  this  reason  the  ordinary 


1014      FIRE   PREVENTION   AND   FIRE   PROTECTION 

alarm  gong  is  objectionable  by  reason  of  its  association  in  the 
public  mind  with  fire  dangers,  and  the  use  of  small  bells  —  some- 
what larger  and  of  a  softer  tone  than  telephone  bells  —  is  pre- 
ferred; in  some  cases  small  air  whistles  are  used. 

All  fire  signals  throughout  the  building  should  be  transmitted 
by  an  electrically  operated  circuit  to  the  office  of  the  chief  of  fire 
drill  and  to  the  chief  of  fire  brigade  headquarters. 

The  recording  device  for  the  chief  of  fire  drill  should  consist 
of  a  punching  register  and  tap  bell;  for  the  chief  of  brigade  there 
should  be  a  combined  gong  and  visual  indicator. 

From  the  office  of  chief  of  brigade  signals  will  be  transmitted 
to  the  fire  district  from  which  the  box  was  pulled  and  also  in  the 
two  adjoining  or  other  sections,  as  may  be  necessary. 


THEATRES. 

Importance  of  Drills.  — 

The  records  of  almost  every  theatre  disaster  will  show  that 
the  critical  moment  in  determining  the  fate  of  the  audience  has 
been  at  the  instant  following  the  first  indication  of  alarm,  and 
that  many,  if  not  a  large  majority,  of  these  disasters  could  have 
been  wholly  avoided  had  there  been  some  prearranged  plan  for 
concerted  action  on  the  part  of  the  house  employees. 

Fire  drill  training  for  theatre  attendants  should  therefore  be 
directed  more  to  the  prevention  of  panics  than  to  futile  attempts 
at  regulating  the  movements  of  a  panic-stricken  audience. 

The  wide  disparity  in  numbers  alone  between  the  available 
house  force  and  the  audience  would  make  any  attempt  at  regu- 
lation ineffective. 

There  are,  however,  certain  well  defined  rules  with  reference 
to  the  duties  of  the  house  attendants  which,  if  carefully  observed, 
will  materially  assist  in  directing  the  movements  of  an  audience 
following  an  alarm  of  fire. 

Organization  of  Employees.  — 

To  insure  the  best  results,  all  employees  permanently  con- 
nected with  the  theatre  should  be  organized  into  fire  drill  com- 
panies, with  special  duties  assigned  to  each.  While  it  is  necessary 
and  important  that  the  members  of  these  companies  be  drilled 
and  instructed  in  the  handling  and  use  of  all  fire  equipment,  and 
properly  trained  in  the  work  of  fire  extinguishment,  the  first 
consideration  is  the  safety  of  the  audience,  and  every  possible 
effort  should  be  made  in  rendering  assistance  to  the  ushers  in 
effecting  a  prompt  and  orderly  dismissal  of  the  audience.  This 
work  will  devolve  mainly  on  the  house  employees  in  the  audi- 
torium and  business  offices,  including  the  door  attendants. 

The  fire  records  show  that  mostly  all  theatre  fires  originate 
on  the  stage  and  that  fires  in  the  auditorium  are  of  infrequent 
occurrence.  Mr.  John  R.  Freeman,  who  has  made  a  study  of 
theatre  conditions,  is  authority  for  the  statement  'That  in  the 


FIRE   DRILLS  1015 

great  theatre  fires  of  history,  the  loss  of  life  has  commonly  re- 
sulted from  spread  of  flames  on  a  stage  covered  with  scenery, 
followed  within  two  or  three  minutes  by  an  outpouring  of  suffo- 
cating smoke  through  the  proscenium  arch  into  the  top  of  the 
auditorium  before  those  in  the  gallery  could  escape.'  Fire 
brigade  work  is  therefore  necessary,  mainly  for  the  stage  section. 

Fire  Alarms.  — 

All  fire  signals  should  be  transmitted  by  an  electrically 
operated  alarm  system.  Recording  apparatus,  consisting  of 
punching  register  and  tap  bell,  should  be  placed  in  the  main 
business  office  or  in  the  box  office  and  also  in  the  office  of  stage 
manager,  provided  there  is  someone  on  duty  in  these  offices 
during  the  entire  performance. 

Announcement  to  Audience.  — 

Upon  receipt  of  an  alarm  by  the  stage  manager,  or  when  fire 
is  discovered  in  the  stage  section  before  an  alarm  is  struck,  the 
curtain  should  be  dropped  immediately  and  the  stage  manager 
or  someone  of  the  actors  whom  he  may  designate,  should  come 
before  the  curtain  and  announce  the  discontinuance  of  the  per- 
formance. Upon  the  wording  of  the  announcement  and  the 
manner  of  its  delivery  will  depend  largely  the  conduct  of  the 
audience,  and  it  is  strongly  recommended  that  a  form  of  announce- 
ment be  prepared  and  printed  or  typewritten  and  copies  thereof 
placed  at  the  punching  register  and  also  in  the  hands  of  the 
various  stage  employees.  The  announcement  should  be  brief 
and  somewhat  after  the  following  order: 

*I  am  instructed  by  the  management  to  announce  that  it  will 
be  necessary  to  discontinue  the  performance  and  to  dismiss  the 
audience  immediately.  The  management  further  requests  that 
each  one  remain  seated  until  music  is  furnished  by  the  orchestra 
and  in  leaving  the  house  to  follow  the  direction  of  the  ushers 
stationed  in  each  aisle.' 

Exits.  - 

While  the  announcement  is  being  made  each  usher  and  door- 
man in  the  parquet,  balcony  and  galleries  will  move  forward  in 
the  aisles  and  give  oral  direction  to  each  section  as  to  the  exit  to 
be  used;  the  orchestra  meanwhile  having  begun  playing  suit- 
able march  time  music.  It  has  been  repeatedly  shown  that  the 
orchestra  offers  one  of  the  most  effective  means  known  for  con- 
trolling theatre  audiences  in  times  of  threatened  panic. 

For  the  assignment  of  exits  the  seating  plan  on  each  floor 
should  be  divided  into  sections,  and  to  each  section  there  should 
be  assigned  certain  exits,  according  to  the  relative  discharging 
capacities,  so  that  the  time  required  for  discharging  the  number 
apportioned  to  any  one  exit  would  average  about  the  same  for 
all.  Each  usher  and  doorman  should  be  provided  with  a  copy 
of  seating  plan,  on  which  should  be  indicated  the  exit  assignments 
in  detail.  Ushers  should  be  required  to  remain  on  duty  in  their 
respective  sections  throughout  each  performance. 


1016      FIRE   PREVENTION   AND   FIRE   PROTECTION 

In  addition  to  the  lights  over  the  exits  there  should  be  a 
number  of  signs,  preferably  of  the  illuminated  type,  conspicuously 
displayed  on  each  floor,  indicating  the  location  of  all  exits. 

Fire  Alarm  Boxes.  — 

Fire  alarm  boxes  should  be  placed  where  they  can  be  con- 
veniently reached,  but  not  in  general  view  of  the  audience.  For 
the  average  theatre  there  should  be  a  box  on  each  side  of  the 
parquet  on  the  wall  and  in  rear  of  last  row  of  seats  and  one  box 
in  main  lobby  near  the  doorway.  For  balcony  and  galleries  there 
should  be  two  boxes,  one  at  each  side  of  theatre  behind  the  last 
row  of  seats.  For  the  stage  there  should  be  one  box  on  the  rear 
wall  and  a  box  on  each  side  near  the  proscenium  wall,  and  where 
necessary  additional  boxes  in  dressing  room  quarters  and  car- 
penter shop.  The  boxes  in  the  auditorium  should  operate  as 
noiselessly  as  possible  to  avoid  calling  attention  thereto. 

An  auxiliary  box  connected  with  the  city  alarm  circuit  should 
be  installed  in  the  stage  section  and  in  the  main  business  office. 

Uniformed  Firemen.  — 

The  practice  of  assigning  firemen  in  uniform  to  theatres 
during  performances  is  to  be  commended;  their  presence  may 
serve  to  inspire  confidence  and  to  reassure  the  audience  in  case 
of  alarm;  they  may  also  render  valuable  assistance  in  the  work 
of  fire  extinguishment.  It  is  believed  that  in  addition  to  assign- 
ing firemen  to  the  parquet  floor  they  should  also  be  stationed  in 
the  balconies. 

Organization  of  Fire  Companies.  — 

For  fire  extinguishing  work  the  fire  drill  organization  should 
consist  of  two  companies,  each  under  the  direction  of  a  captain. 

One  company  to  include  all  employees  in  the  auditorium 
and  offices,  ushers  and  orchestra  excepted,  to  be  known  as  Com- 
pany No.  1.  A  second  company  to  include  all  employees  in  the 
stage  section,  to  be  known  as  Company  No.  2. 

The  captain  of  each  company  should  be  someone  in  authority; 
for  No.  1  Company  the  house  manager  or  one  of  his  assistants; 
for  Company  No.  2  the  stage  manager  or  one  of  the  more  intelli- 
gent stage  mechanics. 

Each  member  of  both  companies  to  be  assigned  to  duties  as 
follows : 

For  each  hose  stream  —  one  valveman  and  two  pipemen;  the 
valvemen  to  remain  at  valve  on  standpipe,  turn  on  or  off  water, 
and  pipemen  to  direct  and  hold  play-pipe  and  to  stretch  hose  line. 

Chemical  engine  men:  three  men  to  be  assigned  to  each 
engine,  one  man  to  remain  at  tank  to  operate  main  valve  and  two 
men  to  unreel  hose  and  direct  nozzle. 

Where  additional  men  are  available  they  should  be  assigned 
to  the  use  of  the  hand  extinguishers,  axes  and  fire  hooks. 

The  stage  electrician  should  be  attached  to  Company  No.  2 
and  be  subject  to  the  direction  of  the  captain.  He  should  make 


FIRE    DRILLS  1017 

a  daily  test  of  the  alarm  system  from  alternate  boxes  and  keep  a 
record  thereof. 

Where  automatic  sprinkler  systems  are  installed,  all  valves 
controlling  water  supply  to  the  system  should  be  strapped  open 
and  regularly  inspected  by  the  house  plumber.  Report  thereof 
to  be  made  weekly  to  the  captain. 

One  member  of  each  company  should  be  assigned  to  make 
daily  inspection  of  all  fire  escapes,  exits  and  stairways,  and,  where 
doors  are  not  provided  with  automatic  opening  devices,  to  see 
that  they  are  unlocked  and  ready  for  instant  use.  Particular 
attention  should  be  given  to  fire  escapes  where  exposed  to  accumu- 
lations of  snow  and  ice.  Prompt  report  should  be  made  to  the 
house  manager  of  any  condition  existing  in  violation  of  rules. 

Cards  of  instructions  containing  full  information  regarding 
rules  and  duties  for  fire  drill  work  should  be  posted  in  both  the 
auditorium  and  stage  sections. 


INDEX 


Note:  Numbers  refer  to  pages.      Illustrations  are  indicated  by 
an  asterisk  after  the  page  number. 


Abacus""  No.  1  door,  477. 
No.  2  door,  480. 
No.  3  door,  491,  492  *. 
No.  4  shutter,  436,  437  *, 

438*. 

ibbey  Theatre,  N.  Y.,  716. 
idams  Building,  Chicago,  362  *,  376*. 
Aero  "  automatic  fire  alarms,  915. 
dr-pressure  tanks,  for  sprinklers,  876. 
Aisles,  in  theatres,  714. 
Ajax  "  fire  doors,  476  *. 
Harm  valves,  877,  879  *,  880  *,  881  *, 

994. 
Ubany,  N.  Y.,  Capitol  Building,  836, 

922. 
Allowances  for  automatic  fire  alarms, 

918. 
sprinkler     protection, 

906. 

watchmen  and  watch- 
clocks,  957. 
.melia    Apartments,    Akron,    Ohio, 

412*,  525,  639*,  640*. 
inchorage  for  walls,  644. 
Apartment  Houses,  297. 
rches,  see  Terra-cotta  Arches,  Con- 
crete   Arches,    Brick    Arches,    etc. 
See  also  Floors. 

.rchitect,  responsibility  of,  322. 
rchitectural     Terra-cotta.      See 
Terra-cotta. 
Arion  Club,  N.  Y.,  328. 
Aronson  Building,  San  Francisco,  353. 
Armories,  306. 
Asbestolith,  see  Sorel  Stone. 
Asbestos,  building  lumber,  263. 
-cement  products,  263. 
-clad' doors,  470. 
corrugated  sheathing,  264. 
curtains,   723,   728*,   729*. 
fire-resistance  of,  263,  723. 
manufacture  of,  262. 
metallic  cloth,  723. 
protected  metal,  268. 
roofing,  683. 
shingles,  686. 
Asch  Building  fire,  186,  187  *,  189  *, 

422,  535,  810. 
Ash  cans,  metal,  30. 
Asphalt  floors,  341. 

stair  treads,  524. 
Assembly  halls,  750. 


Associated  Factory  Mutual  Labora- 
tories, 121. 
Attic  spaces,  675. 
"Auto-exposure,"  311,  421. 
Automatic  alarms,  see  Fire  Alarms, 
appliances,  857. 
doors,     486,     487*,     488, 

492  *,  493  *. 

fire  alarms,  see  Fire  Alarms, 
fusible  links,  488  *,  489  *. 
inspection     and     mainte- 
nance of,  997. 
sprinklers,  See  Sprinklers, 
windows,  449  *. 
Automobiles,  814. 
Auxiliary  boxes,  955,  957. 
Auxiliary  equipment,   851,   860,   862. 

See  also  Equipment. 
Ayer  Mills,  792. 

B 

Baker  Building,  Boston,  527  *. 
Baldwin  Locomotive  Works,  fire,  903. 
Baltimore  &  Ohio  R.  R.  Co. 'a  Build- 
ing, 160*. 

Baltimore     conflagration,  automatic 
fire  alarms  in,  917. 
beam  and  girder  protec- 
tions in,    580,    581  *, 
582*. 

column  failures  in,  348. 
concrete  construction  in, 

176. 

deductions  in  re,  176. 
description  of,  155. 
Equitable  Building,  163*. 
faulty   construction     in, 

318. 
fire-resisting      buildings 

in,  162. 

lessons  of,  3 1 9. 
losses   on     buildings   in, 

193. 

map  of,  158  *. 
mullions  in,  656. 
partitions  in,  384. 
ratio  of    fire  damage  to 
sound  value  in  build- 
ings, 202. 
safes  in,  828. 
steel  buildings  in,  212. 
terra-cotta  in,  238,  594, 
658. 


1019 


1020 


INDEX 


Baltimore    conflagration,    vaults    in, 

830. 
wall  construction  in,  634, 

645. 
window    protection     in, 

422,  429,  435,  461. 

Baltimore   "News"   Building,   condi- 
tion of  metal  reinforcement  in,  276. 
Bank  of  State  of.  N.  Y.,  condition  of 

iron  in,  273. 
Basement  fires,  892. 
Basement  sprinklers    from    firemen's 
standpoint,  892. 
from     insurance     stand- 
point, 893. 
N.   Y.   laws  regarding, 

894. 

principle  of,  891. 
Beam  protections,  concrete,  608,  609*, 

611  *,  612*. 

fire-resistance  of,  342,  580. 
in  Baltimore  fire,  580,  581  *, 

582*. 
eoffit    tile    for,    578,    583  *, 

584*. 

terra-cotta,  582  *. 
Beams,    calculation  of,  331. 
tables  of,  332,  333. 
Belt  openings  in  walls,  645,  646*. 
Berger    Mfg.    Co.'s    economy    studs, 

359*,  360*. 

Berkeley  Building,  Boston,  627  *. 
"Bi-sectional"  fire  walls,  302,  303  *. 
Boiler  rooms,  313,  701,  741,  816. 
Books,  on  fire  protection,  insurance, 

etc.,  36. 
Book    tile    roof     construction,     667, 

678*,  679*. 

Boston  Art  Museum,  447  *. 
Boston  Manufacturers'    Mutual    Fire 

Ins.  Co.,  895. 

Opera  House,  702  *. 

Public  Library,  328. 

Breweries,  insulated  floors  for,  335. 

Brick,    chemical  properties,  219. 

column  protections,  354,  369*. 
column      protections,      U.  S. 

Goyt.  specifications,  370. 
deterioration  of,  284. 
face,  223. 
fire  tests  of,  220. 
floor  arches,  325,  326  *,  327  *. 
glazed,  224. 
"Haverstraw  "  hollow,  570*, 

647. 

hollow,  647. 

method  of  manufacture,  219. 
methods  of  use,  220. 
pressed,  223. 
roof  coverings,  681. 
sand-lime,  221. 

sand-lime  fire-resisting  quali- 
ties, 222. 

walls,  633,  634,  637,  643,  645. 
work,  637. 
British  Fire  Prevention   Committee, 

objects  of,  114. 

Broadway  Chambers,  N.  Y.,  653  *. 
Brooklyn  Theatre  fire,  698. 


Brown     Hoisting     Machinery     Co.'s 

Bldg.  fire.Cleveland,  674. 
Building    Code,    National    Board    oJ 

of  F.  U.,  32,  421. 
Building  laws,  31,  318. 
Bureau    of   violations    and    auxiliary 

fire  appliances,  N.  Y.,  967. 
Bush   St.   Telephone   Exchange,   Sar 

Francisco,  424,  461. 
Butterick  Building,  concrete  work  in 

322. 


Cabot's  quilt,  415. 

Cadillac    Automobile    factory,     De< 

troit,  586  *. 
Calcium  chloride  solutions,  etc.,  882 

928. 
Calvert     Building,     Baltimore      fire 

159*.  167,  352*,  582*. 
Capacity  of  stairs,  509,  533. 
Car  barns,  306,  905. 
Carelessness,  as  cause  of  fires,  26,  757 
Care  of  premises,  807,  824. 
Casement  windows,  446,  785,   786* 

787*. 

Cast-iron,   as  used  in  buildings,  214 
columns,  fire-resistance  of 

214. 

columns,  fire  tests  of,  215 
corrosion  of,  273. 
trim    for    partitions,    etc. 

413*. 
Cathedral   of   St.   John    the   Divine 

328. 
Causes  of  fires,  26,  28,  29,  698,  758 

814,  838,  845,  861. 
Ceiling  blocks,  677,  678  *,  679  *. 
Ceilings,    level,  preferable,  343. 
over  basements,  765. 
suspended,    see    Suspende< 

Ceilings. 
Cement,  floorings,  340. 

mortar,    fire-resistance    oi 

256. 
permeability  and    porosit 

of,  283. 

protective  qualities  of,  27C 
trim,  412. 

Central  National  Bank,  N.  Y.,  515  * 
Central  station  sprinkler  supervision 

919,  920. 

watchman  supervision,  952 
"Century  Sheathing,"  264. 
Chandler  Store,  Boston,  503  *. 
Charcoal,    spontaneous    ignition    ol 

840. 

Character  of  building,  297. 
Check-    and    gate-valves,    877,    962 

972,  988. 

Chelsea  conflagration,  185,  663. 
Chemical    fire    extinguishers,     929  * 

932,  933. 
Chesapeake  &  Potomac  Bldg.,  Balti 

more  Fire,  174  *. 
Chicago  and  Northwestern  Terminal 

329*. 

Chicago    Athletic    Club    Bldg.    fire 
135,  422. 


INDEX 


1021 


Chicago  Post  Office,  280,  365  *. 
Chicago  Savings  Bank  Building,  375*. 
Chimneys  and  flues,  759,  760  *,  761  *, 

772*. 

Churches,  306. 
Cinder  concrete,  250,  288,  339. 

conductivity  of,  355. 
Cinder  concrete  fill,  339. 
Cinders,  250. 

Cleaning  of  steel  work,  278. 
Closets,  in  residences,  765. 
Coal,     spontaneous    combustion    of, 

839. 

Cocheco  Mill  fire,  902. 
Cold  storage  insulation,  649. 
Collinwood  school  fire,  740. 
"Columbia"  fire  testing  station,  124. 
Column  protections,  action  of  in  vari- 
ous fires,  349. 
brick,  354,  369  *. 
conclusions,  380. 
concrete,     353,     366,     367*, 

368  *,  369  *. 
conductivity  of,  355. 
essentials  for,  355. 
failures  of  in  Baltimore  and 
San    Francisco    buildings, 
348. 

importance  of,  347. 
metal  lath  and  plaster,  349, 

359,360*. 
pipe   spaces  in,    373,    375  *, 

376*. 

plaster  of  Paris,  350,  360. 
reinforced       concrete,      371, 

372*. 

solid  vs.  hollow,  357. 
terra-cotta,    350,  360,  361*, 
362*,  363*.  364*,  365*. 
366*,  372*. 

terra-cotta,    U.    S.     govern- 
ment practice,  366. 
thickness  of,  358. 
types  of,  359. 
Columns,  cast-iron,  fire-resistance  of, 

214. 

cast-iron,  fire  tests  of,  215. 
concrete-filled,  282,  373. 
failure  of,  348. 
guards  for,  377. 
mill  construction,  79. 
"Monarch"  tile  block,  378*. 
"Na'tco,"  379*. 
protection       of       interiors 

against  corrosion,  281. 
reinforced  terra-cotta,  379*. 
steel,  tests  of,  212. 
terra-cotta  tile,  377. 
wall,  660,  661*.  662*. 
Combination  concrete  and  mill  con- 
struction, 800,  801  *,  802  *,  803  *, 
804. 

Combination  end-  and  side-construc- 
tion arches,  see  Terra-cotta  Arches. 
Combination  floors,  efficiency  of,  631. 
fire  tests  of,  631. 
for      residences,      772, 
773*.  774*. 


Combination  floors,  National  Fire 
Proofing  Co.'s,  625, 
626*.  627*.  773*. 
774*. 

recommendations,  625. 
safe  loads  for,  628,  629. 
used    in   War    College 
Bldg.,  Wash.,  D.  C., 
630,  631  *. 
weights  of,  628,  629. 
with   plaster-block  fil- 
lers, 630. 
Combination  tile  and  concrete  walls, 

781*. 
Combination  wall  constructions,  for 

residences,  780*,  781  *. 
Common  hazards,  30. 
"Composite  "  doors,  474. 
Composition  blocks,  etc.,  see  Plaster 

of  Paris, 
roofing,  683. 

Concrete  beam  protections,  608,  609  *. 
block  partitions,  408. 
blocks,  conductivity  of,  254. 
fire  tests  of,  254. 
manufacture  of,  252. 
block  walls,  642,  776,  777  *, 

778*. 

British  Fire  Prevention 
Committee's  tests  of,  243, 
614. 

building  tile,  777  *,  778  *. 
cinder,  288. 
column  forms,  367  *. 
column     protections,      353, 

366,  367*,  368*,  369*. 
composition  of,  240,  604. 
conclusions,  250,  252. 
conductivity  of,  355. 
dehydration  of,  373. 
design  and  use  of,  240,  602. 
factories,  800,  804. 
filled  columns,  282,  373. 
fireproofing  of,  249. 
fire-resisting  qualities,    242, 

613. 

floors,  advantages   and  dis- 
advantages of,  623. 
"Armocrete  "  system, 
test  of,  617,  618*. 
beam  and  girder  pro- 
tections, 608. 
blast-furnace        slag, 

619. 
"  Coignet  "      system, 

test  of,  617. 
composition  of,  604. 
conclusions,  620. 
deflection  of,  622. 
design  of,  602. 
flush       ceiling       con- 
struction, 607, 
608*. 
in       San       Francisco 

buildings,  620. 
insulated,  335,   336*. 
"Kahn"  system,  test 
of,  613. 


1022 


INDEX 


Concrete  floors, 

"Mushroom "      sys- 
tem, 612. 

paneled  ceiling   con- 
struction,         605, 
606  *,  607  *. 
paneled-slab         con- 
struction, 612. 
position       of       rein- 
forcement in,   603, 
622. 
reconstruction        of, 

621. 
reinforcement         in, 

603,  604. 
"  separately-moulded 

system,"  613. 
suspended      ceilings, 

for,  611*,  612*. 
tests  of,  613,  etc. 
thickness  and  weight 

of,  602. 

types  of,  601.  , 

"Unit"  system,  613. 
waterproofing  of ,  335. 
German  fire  tests  of,  242. 
girder    protections,     608, 

609*,  610*,  611*. 
in  Baltimore  fire,  176. 
in  San  Francisco  fire,  245, 

620. 
loss   of    strength    of   under 

fire,  248. 
N.  Y.      building      dept's., 

tests  of,  243,  613. 
partitions,  407. 
protective  qualities  of,  286. 
residences,  776. 
roofs,  665,  666  *. 
rusting  of  steel  in,  286. 
stairs,  526,  527  *,  528  *. 
thermal     conductivity     of, 

247. 
U.  S.  geological  survey  tests 

of,  244. 
vaults,  832. 

vs.  terra-cotta,  235,  252. 
walls,  641,  649,  650. 
Conductivity  of  materials,  355. 
Conflagration  liability,  60. 
Conflagrations,  Baltimore,    map    of, 

158*. 
causes  and  remedies, 

203. 

Chelsea,  185. 
comparative  areas  of 
Chicago,  Baltimore 
and  San  Francisco, 
8*. 
list     of     notable,     in 

U.  S.,  7. 

Paterson,  N.  J.,  150. 
San  Francisco,  178. 
statistics  in  re,  6. 
temperatures  in,  192. 
Conservatory  of  Music,  Boston,  415. 
Continental  Trust  Co.'s  Bldg.,  Balti- 
more   fire,     171,    352*,     404,    420, 
581*.  644,  657,  830. 


Contractor,  responsibility  of,  323. 
Copley-Plaza  Hotel,  Boston,  655  *. 
Copper  covered  doors,  470. 
Corn  Exchange  Bank  Bldg.,  Chicago 

438*. 
Cornices,     terra-cotta,     657,     658  * 

659*. 
Corrosion,  cast  iron,  273. 

causes  of,  in  buildings,  272. 
importance    of    protection 

against,  271. 
of  sprinkler  heads,  992. 
patent  plasters,  284. 
protection    of    column    in- 
teriors, 281. 
relation  of  to  fireproofing, 

steel,  273. 
Corrugated-iron  doors,  476,  477  *. 

shutters,  433  *,  434. 
Costs,  efficiency  vs.  inefficiency,  322. 
factories,  etc.,  100,  803~ 
fire-resisting  materials,  210. 
maintenance  of  residences,  789. 
mill   construction,    100,    102  *, 

103  *,  104  *. 

percentages    of,    on    items    ofi 
construction  in  fire-resisting 
buildings,  195. 
residences,  787. 
schools,  754. 
theatres,  739. 
tin-covered  shutters,  465. 
windows,  metal  and  wire  glass, 

465. 

Court  walls,  655. 
Curtains,  theatre,  see  Theatres. 
Curtain  walls,  633,  656. 

D 

"Dahlstrom"   metallic  doors,   483*, 

484  *,  485  *,  498  *. 

Damage  by  fire,  to  Baltimore  build- 
ings, 202. 

Dead  loads,  on  floors,  330. 
Denver,    Colo.,   tests    of    terra-cotta i 

arches,  588. 

Department  stores,  design  of,  298. 
Depreciation  of  factories,  etc.,  805. 
Design,  296. 

character  of  building,  297. 
column  protections,  347. 
elimination    of    combustible 

materials,  315. 
equipment,  315. 
factories,  791. 
floors,  324,  330. 
garages,  816. 
installation     of     mechanical 

features,  314. 
isolation  of  mechanical  plants, 

313. 
light-shafts       and       interioi 

courts,  310. 

location    and    exposure    haz- 
ard, 304. 

means    of    egress,    300,    717 
811. 


INDEX 


1023 


Design,  partitions,     381. 

requirements  of,  296. 
residences,  757,  etc. 
schools,  740,  743,  etc. 
stairs,  501,  509. 
subdivision   of    large    areas, 

305. 

theatres,  697,  699,  701,  etc. 
vertical  openings,  312. 
Deterioration,  causes  of,  in  buildings, 

272. 

Detroit  Opera  House,  fire  in,  640. 
Domes,  Guastavino,  328. 
Door  bucks,  steel,  409. 
Door  frames,  for  rough  doors,  494  *. 
Doors,  "Abacus  No.  3,"  492*. 
"Ajax,"  476*. 
automatic  horizontal,  488. 
automatic  vertical,  487. 
automatically  closing,  486. 
care  and  maintenance  of,  500. 
composite,  474,  476*. 
copper-covered,  470. 
corrugated-iron,  476,  477  *. 
"Dahlstrom,"      483*,     484*, 

485*. 
double  fire,  489,  491  *,  492  *, 

493*. 
double     steel     rolling,     492  *, 

493*. 

for  belt  openings,  645,  646  *. 
frames  for,  494  *,  495  *. 
fusible  links  for,  488  *,  489  *. 
garage,  821,  822*,  824*. 
jambs  and  trim  for,  497  *. 
kalamine,  481,  482*. 

trim  for,  497  *. 
Kinnear,  477,  480,  491,  492  *. 
metallic,  483  *,  484  *,  485  *. 

trim  for,  498  *. 
opening  devices  for,  716. 
party  wall,  490  *. 
"Peelle,"  822  *,  824  *. 
plate-iron,  471,  490,  491  *. 
requisites  for,  466. 
"Richardson,"  482*. 
"Saino,"  477*. 
shaft  opening,  645,  646  *. 
steel  rolling,  476,  478  *,  479  *, 

491,  492*,  493*. 
theatre  requirements  for,  716. 
tin-  and  asbestos-clad,  470. 
tin-clad,  467,  468  *,  489,  490  *. 
trap,  489. 

"Turn  Over,"  824  *. 
types  of,  466. 
vault,  832,  833. 
wall  pocket  for,  490  *. 
"Wilson  Arrangement  No.  1," 

478*,  479*. 
Wilson,   with  arched  lobbies, 

493*. 

Door  sills,  494,  495  *,  496  *. 
Double-glazed  sash,  452,  453  *. 
Druecker  warehouses,  Chicago,  367  *. 
Dry-pipe  sprinklers,  air-pressure  for, 

883. 

disadvantages 
of,  8«2. 


Dry-pipe    sprinklers,    installation   of, 

883. 
principles   of, 

881. 

vs.  wet-pipe,  882. 
Dry  rot  in  timbers,  98,  799. 
Dumb  waiter  enclosures,  545. 

E 

Education,  in  fire  prevention,  31. 

Electric  wiring,  763. 

Elevator  enclosures,  doors    for,    499, 

823. 

in  garages,  821. 
types  of,  540. 

Elimination  of  combustible  or  dam- 
ageable materials,  315. 
Emergency  access,  303. 
Emergency  egress,  301. 
Employees,  safety  of,  in  factories,  809. 
End-construction  arches,   see  Terra- 
cotta Arches. 
Escalators,  718. 
"Esty"  sprinkler  head,  872  *. 
Equipment  auxiliary,  851,  860,  862. 
for  yard  hose  houses,  982. 
in  factories,  806. 
necessity    for,    315,    851, 

860. 
rating     for,     in     typical 

building,  67. 
theatre,  736. 
Equitable  Building,  Baltimore,  163  *, 

335,  645. 
Equitable  Building,  New  York,  504, 

834,  855,  973. 
"Excelsior"   hollow  tile  arches,    567, 

568*. 
Exits,  school,  749. 

theatre,  701. 

Expanded  metal  lath,  691  *,  692  *. 
Explosives,  843. 
Exposure  hazard,  causes  of,  34. 

locations  involving, 

304. 
protection  against, 

418. 
rating     in     typical 

building,  66. 
roofo  in,  663. 

Extent  of  fires,  in  European  cities,  15. 
in  U.  S.  and  Europe 

compared,  14. 
External  hazard,  204. 


Face-brick,  223. 

Factories,  combination  concrete  and 

mill      construction,       800, 
801  *,  802  *,  803  *. 

concrete,  800. 

costs  of,  100,  803. 

depreciation  of,  805. 

design  of,  298,  302,  791. 

equipment  for,  80*5. 

fire  alarm  systems  in,  812. 

fire  drills  in,  813. 


1024 


INDEX 


Factories,  fire  protection  for,  806. 
insurance  of,  808. 
light  and  windows  in,  792, 

793*. 

management  in,  807. 
means  of  egress,  811. 
mill  construction,  69,  etc., 

798. 

rigidity,  797. 
roofs,  795. 
safety    of    employees    in, 

809. 

shafting  for,  794,  795  *. 
steel-frame,  797,  799. 
subdivision  of  large  areas 

in,  306. 

types  of  construction,  791. 
water-tight  floors,  794. 
Factors  of  safety  in  re  fire  protection, 

323. 

"Fair"  Building,  Chicago,  364*. 
Fairmont  Hotel,  San  Francisco,  387. 
P'aulty  construction,  204,  272,  317. 

causes  of,  320. 
Ferro-asbestic  doors,  474. 
Ferroinclave,  269,  674. 

roofing,  269  *,  685. 
siding,  270. 

Filene  Building,  Boston,  375  *,  662  *. 
Fine  Arts  Building,  St.  Louis,  328. 
Fire  alarms,  "aero,"  915. 

allowances  for,  918. 
automatic,  908,  910. 
central  station  watch, 

954. 

department  store,  1013. 
efficiency  of,  909. 
factory,  812,  1005. 
in    Baltimore   conflagra- 
tion, 917. 

installation  of,  911. 
in  theatres,  1016. 
journal-bearing,          916, 

917*. 

manual,  911,  921,  955. 
school,  752  *,  1009. 
signal    stations    for,    in 
Boston  schools,  752  *. 
sprinkler,  919. 
thermostats,  912. 
types     of,     911,     914*, 

915*.  917*. 
vapor,  916. 
Fire  curtains,  721. 

asbestos,  723. 
Austrian    experiments, 

721. 
fire-resistance   of,    722, 

723,  etc. 

functions  of,  722. 
Kinnear,  726*.  727*. 
metallic,  724. 
steel  and  asbestos,  728*, 

729*. 

types    of,    722,    725*, 
726*,    727*.    728*, 
729*. 
under  roofs,  674. 


Fire  departments,  limitations  of,  852, 

856,  858. 

discovery  of,  908. 
drills,  300,  301,  979,  1000. 

in  department  stores,  1010. 
in  factories,  813,  1002. 
in  schools,  753,  1006. 
in  theatres,  738,  1014. 
Fire  escapes,  300,  528. 

access  to  roof  from,  539. 
Boston       requirements, 

534*. 
circular      stair,      536  *, 

537. 

drop  ladders  for,  535. 
exterior,  533,  719  *. 
factory,  811. 
Hamburg,  531,  532*. 
interior,      529  *,     530  *, 

532*. 
Kirker-Bender,          537, 

538*. 
New  Jersey  regulations 

in  re,  534. 
on      Iroquois      theatre, 

719*. 
Philadelphia,  529*, 

530  *. 

requirements  for,  528. 
school,  751. 
theatre,  719*. 
tower,  529*,  530*,  531, 

532  *. 

windows  at,  535. 
Fire  (chemical)   extinguishers,   929  *, 

932,  933. 

Fire  (powder)  extinguishers,  936. 
Fire  insurance,  agents,  39. 
a  tax,  57. 
example  of,  in  typical 

building,  63. 
factories,  808. 
inspection  bureaus, 

56. 

methods  of  rating,  40. 
Mutual      Companies, 

56. 
National      Board      of 

F.  U.,  50. 

Origin  of  in  U.  S.,  38. 
rating      for      typical 

building,  65. 
rating  organizations, 

49. 

rating      slip,     Boston 
Board  of  F.  U.  for 
fireproof  bldg.,   45. 
relation    of   to   build- 
ing construction,  61. 
statistics  of,  in  U.  S., 

58. 

"Universal"  Mercan- 
tile    Schedule,    41. 
Fire  losses,  annual  in  U.  S.,  2. 

comparative  in  U.  S.  and 

Europe,  11,  21. 
compared      with      U.  S. 

National  debt,  etc.,  4. 
causes  of  in  U.  S.,  16. 


INDEX 


1025 


ire  losses,  in  buildings,  compared  to 
sound  valve,  202. 
increase  year  by  year,  3. 
in  Italian  cities,  14. 
minimizing  of,  205. 
on    Baltimore    buildings, 

193. 

per  capita  in  U.  S.,  9,  12, 
-     18. 
per  capita  in  U.  S.,  and 

European  cities,  13. 
ire  pails,  922,  926  *,  927,  933. 
re  prevention,  defined,  24. 
ireproof,  defined,  207. 
paints,  939. 

ireproofed  wood,  260,  412. 
ire  protection,  cost  of  in  U.  S.,  9. 

courses     of     instruc- 
tion in,  35. 
denned,  33. 
library,  36. 
requirements    for 

complete,  851. 
ire  pumps,  876,  961. 
ire-resisting  buildings,  denned,  295. 
ire-resisting    construction,    see    also 

Design. 

definition  of,  207. 
efficiency  of,  317,  323. 
first  test  of,  130. 
requirements  for,  296. 
ire-retarding  paints,  938. 

solutions,  940. 
ires,  Asch     Building,      186,      187*, 

189*,  422,  535,  810. 
Baldwin    Locomotive    Works, 

903. 
Baltimore     and     Ohio     R.  R. 

Co.'s  Bldg.,  160*. 
Baltimore  conflagration,   155. 
Calvert    Building,    159*,  167, 

352  *,  582  *. 
causes  of,  26,  28,  29,  698,  758, 

814,  838,  845,  861. 
Chelsea  conflagration,  185,  663. 
Chesapeake  &  Potomac  Bldg., 

174*. 
Chicago  Athletic   Club   Bldg., 

135,  422. 

Cocheco  Mill,  902. 
Collinwood  school,  740. 
Continental  Trust  Co.'s  Bldg., 
171, -352*,   404,   420,   581  *, 
644,  657,  830. 

control  by  construction,  33. 
Detroit  Opera  House,  640. 
Equitable  Building,  Baltimore, 

163  *,  335,  645. 

Equitable  Building,  New  York, 
504,  834,  855,  973. 

girago,  814. 
irard   Ave.    Theatre,    Phila., 
724. 
Granite    Building,    Rochester, 

177,  385*,  422. 
Herald  Building,  165,  351  *. 
Home    Life    Ins.   Co.'s    Bldg., 
144,    145*,    335,    384,    419, 
420,  853. 


Fires,  Home   Buildings,    Pittsburgh, 

137,  139*,  141  *,  148,  422. 
Hurst  Store  Building,  312,917. 
n  Boston,  1881  to  1909,  25. 
n  fire-resisting  buildings,   127. 
n  mill  construction  warehouse, 

70*. 

n  school  buildings,  740. 
n  sprinklered  risks,  895. 
Iroquois  Theatre,  153,  156*. 

698,  719*. 

losses    on    fire-resisting   build- 
ings, 193. 
Manhattan  Savings  Bank,  129, 

522. 
Maryland    Trust    Co.'s  Bldg., 

170,  581*,  582  *. 
Merchants'     National     Bank, 

174. 

Metropolitan  Opera  House,  132. 
Minneapolis  Lumber  Exchange 

131. 

New  England   Building,   Bos- 
ton, 218. 

Pacific  States  Tel.  &  Tel.  Bldg., 

353,  368*.  439*,  440*,  466. 

Parker     Building,      183,     349, 

351  *,  853. 

Paterson,  N.  J.,  150,  663. 
Phelps  Publishing  Co.'s  Bldg., 

903. 

Roosevelt  Building,  152,  522. 
San  Francisco,  178. 
Schiller  Theatre  Bldg., Chicago, 

640. 

school,  740. 
temperatures  in,  192. 
theatre,  697. 
Union    Trust  Co.'s    Building, 

169,  351*,  581*. 
Vanderbilt  Building,  142. 
yearly  increase  in  number  of, 

24. 

Fire  stops,  763,  764  *,  765  *. 
Fire  walls,  307,  660. 
"First  aids,"  737,  753,  785,  857. 
Fireworks,  844. 
Fisher  Bldg.,  Chicago,  661  *. 
Flat  Iron  Building,  New  York,  412. 
Flood  Building,  San  Francisco,  358. 
Floorings,  finished,  339,  342,  575. 
Floors,  asphalt,  341. 

beam  tables  for,  332,  333. 
brick,  325,  326  *,  327  *. 
cement,  340. 
cinder  fill  for,  339. 
concrete,  see  Concrete  Floors, 
design  of,  324,  330,  602. 
finished,  339,  575. 
garage,  821. 

granolithic,  341. 
uastavino,  328,  329  *,  592. 
hose  holes  in,  337,  338  *. 
insulated,  335,  336  *. 
in     Herald     Building,    Balti- 
more fire,  166  *. 
in  Home  Life  Ins.  Bldg.  fire. 
145*. 


1026 


INDEX 


Floors,  in  Home  Office  Building  fire, 

141*. 
in  Home  Store  Building  fire, 

139*. 

loads  on,  330. 
mill  construction,  77,  83  *. 
monolithic,  259. 
requirements  for  fire-resisting 

design  of,  324. 
segmental,      see       Segmental 

Terra-cotta  Arches, 
steel-woven  oak,  341. 
terra-cotta,  see  Terra-cotta 

Arches, 
terrazo,  341. 
test   requirements    of    N.  Y. 

bldg.  dept.,  123. 
tie-rods  for,  333. 
types  of  fire-resisting,  324. 
types  of   fire-resisting,   selec- 
tion of,  345. 

waterproofing  of,  335,  794. 
Fore  River  Ship  Building  Co.'s  Bldg., 

804. 
Forest  Chambers  Apartments,  N.  Y., 

484  *,  485  *. 

Forest  Theatre,  Phila.,  703. 
Foyers,  in  theatres,  715. 
Freezing  of  fire  pails,  etc.,  924,  927. 
Freight  elevator  enclosure  doors,  499, 

545. 
Frequency  of  fires  in  U.  S.  and  Europe 

compared,  14. 
Furnaces,  763. 

Furred  ceilings,  see  Suspended   Ceil- 
ings. 
Furring,  concrete  wall,  649. 

cornice  and  cove,  691  *. 
exterior  wall,  647. 
gypsum  block,  649. 
hollow  brick,  647. 
insulation,  649. 
metal  and  lathing,  648,  G89. 
terra-cotta,  648*. 
wall,,  647,  648*.  689. 
Fusible  links,  488  *,  489  *,  865. 
solder,  865. 


G 

Garages,  care  of  premises,  824. 
causes  of  fires  in,  814. 
construction  of,  821. 
design  of,  816. 
elevators,      stairways     and 

doors,  821,  822*,  824*. 
filling  of  tanks  on  machines 

in,  817. 

fire  hazards  in,  814. 
floors  in,  821. 
heating,    lighting   and    fires 

in,  816. 

"Peelle"  doors,  822  *,  824  *. 
private,  825. 
public,  815. 

sand  and  deterrents,  823. 
sewer  connections  prohibited 

in,  820. 


Garage,  storage  tanks,  piping,   etc., 

817,  820. 

types  of  construction,  825. 
ventilation  of,  820. 
Gasolene,  storage  of,  etc.,  817,   820, 

839. 

tests  of  burning,  934. 
Gillender  Building,  N.  Y.,  condition- 

of  steel  in,  275,  284. 
Girard  Ave.  Theatre,  Phila.,  724. 
Girder  protections,  brick,  326  *. 

concrete,       327  *, 
608,  609*,  610*, 
611*. 
fire-resistance   of, 

342,  584. 
metal     clips    for, 

587. 

plate-    and    box- 
588,  610*, 

611*. 
raised  skewbacks, 

586*,  587*. 
terra  cotta,  584  *, 
585*,        586*, 
587  *,        609  *, 
610*,  611*. 
Girders,  calculation  of,  331. 

protection  of,  see  Girder  Pro- 
tections. 

tables  of  steel,  332,  333. 
Glass,  see  Prism  Glass,  Wire  Glass. 
Glazed  brick,  223. 

"Glazier"  universal  roof  nozzle,  967  *. 
Grand  Central  Station,  N.  Y.,  448  *, 

449*. 

Grand  Opera  House,  N.  Y.,  736. 
Granite,  action  of,  under  fire,    160*, 

216,  635. 
damage  to,  in  Baltimore  fire, 

160*,  217*. 
fire  tests  of,  218. 
Granite    Building,     Rochester,     177, 

385*,  422. 

Granolithic  floorings,  341.. 
Gravel  roofing,  683. 
Gravity  tanks,  875,  921,  961,  987. 
Grille  elevator  enclosures,  540. 
Grinnell  sprinkler  heads,  871  *,  872  *, 

885*. 
straightway     alarm     valve, 

879*,  880*,  881  *. 

Guastavino,  dome  construction,  328. 
floor    construction,  328, 

329*,  592. 
stair    construction,    525, 

526*. 

Gun  powder,  843,  844. 
Gypsinite  studding,  257,  409. 
Gypsum,  257. 

partition  blocks,  394. 
wall  furring  blocks,  649. 

H 

Hall  of  Justice,  San  Francisco,  387. 
Hall  of  Records,  San  Francisco,  462. 
Hamburg    tower    fire    escapes,    531, 
532*. 


INDEX 


1027 


Hartman  Theatre,  Columbus,  Ohio, 

726.* 

Haverstraw  hollow  brick  arches,  570*. 
furring,  647. 

Heating  apparatus,  741,  763,  816. 
Height  of  building  vs.  fire  protection, 

853,  854,  855. 
Herald  Building,  Baltimore  fire,  165, 

351*. 
"Herringbone"  expanded  metal  lath, 

692*. 

High  pressure  water  supply,  962. 
Home  Life  Ins.  Co.'s  Building,  144, 

145*,  335,  384,  419,  420,  853. 
Home  Buildings,  Pittsburgh,  fire  in, 

137,  139*,  141  *,  148,  422. 
Hose,  automatic  valves  for,  964. 
care  of,  965,  984,  999. 
cotton,  rubber  lined,  983. 
holes  in  floors,  337,  338  *. 
houses    for    yard    use,     981  *, 

983*. 

outlets  and  valves,  963. 
racks  and  reels,  963,  964  *. 
standpipe,  965. 
vs.     hydrants     and     cast-iron 

piping,  984. 
Hose  streams,  efficiency  of,  859. 

extinguishment  of  fires 

by,  858. 
Hotels,  297. 

sprinklers  in,  904. 

"Howard"  swinging  hose  rack,  964  *. 
Hurst  Store  Building,  Baltimore,  312, 

917. 
"Hy-rib"  steel  sheathing,  825. 


Incendiarism,  27. 
Inspection,  318. 

bureaus,  56. 

Inspection     and     maintenance,     im- 
portance of,  986. 
in  theatres,  738. 
of     automatic     fire 

alarms,  997. 
of  sprinklers,  986. 
of    standpipes    and 

hose  racks,  998. 
Insulated  floors,  335,  336  *. 
Insurance,  see  Fire  Insurance. 
Interior  finish,  for  residences,  784. 
Interlocked   plaster-block   partitions, 

396. 
"  International"  sprinkler  head,  872  *, 

885*. 

'Invincible"      terra-cotta     columns, 
379*. 
uois  Theatre,  cross-section    and 

plan  of,  156*. 
fire      escapes      on, 

719*. 

fire  in,  153,  698. 
.ation  of  dangerous      features      in 

garages,  816. 
dangerous         risks         in 
theatres,  701. 


oo 

"Im 

2 


Isolation    of     heating    apparatus    in. 
schools,  741. 

mechanical  features,  314. 
mechanical     plants     and 

special  hazards,  313. 
stairs,    504,    747,    748*, 

749*. 


"Johnson  Long-span"  floor  construc- 
tion, 562  *,  563  *,  564,  774  *. 

Journal-bearing  thermostats,  916, 
917*. 

K 

Kalamine,  doors,  481,  482  *. 
trim,  497  *,  498  *. 
windows,  444  *. 
Keany  Square  Trust   Bldg.,  Boston, 

627*. 

Keith's  Theatre,  Boston,  736,  737. 
Kerosene,  839. 
"Keystone"  plaster-block  partitions, 

395,  397,  415. 
Kinnear    fire    curtains    for    theatres, 

726*,  727*. 

fire  shutters,  436,  437*,  438*. 
steel  rolling  doors,  477,  480, 

491,  492*. 

Kirker-Bender  fire  escapes,  537,  538. 
Kohl   Building,   San  Francisco,    414, 

423,  482. 
Kuhne's  clincher  lath,  693. 


Larkin  Co.'s  Building,  Buffalo,  N.  Y., 

836. 
Light,  311,  792. 

diffusion  of,  267. 
Lighting  of  factories,  792,  793  *. 
garages,  816. 
theatres,  718. 

Lightning,  protection  against,  845. 
Light-shafts  and  interior  courts,  310. 
Lime  mortar,  255. 

permeability   and    por- 
osity of,  283. 
rusting  caused  by,  284. 
Lime-of-Tiel,  257. 
Limestone,  action  of  under  fire,  218, 

635. 
injurious     to      steelwork, 

285. 

Limitations  of  areas,  308,  383. 
Limitation  of  occupancy,  299. 
Live  loads,  on  floors,  331. 
Loads,  dead,  on  floors,  330. 

live,  on  floors,  330. 
Load  tests  and  factor  of  safety,  for 

terra-cotta  arches,  595. 
Location  and  exposure  hazard,   304, 

700,  742. 
Loft  buildings,  299. 

"bi-sectional"      plan 

of,  303  *. 

Loss  of  life  by  fire,  9,  698,  740,  757, 
810,  1000. 


1028 


INDEX 


.  Losses,  fire,  see  Fire  Losses. 
Louisville,  Ky.,  High  School,  538  *. 
Lyman  District  School,  East  Boston, 
743  *,  744  *,  745  *. 

M 

Magneto  recorders,  see  Watch-clocks. 
Magnolith,  see  Sorel  Stone. 
Maintenance  of,  see,  also,  Inspection 
and   Maintenance, 
chemical      fire      ex- 
tinguishers, 930. 
fire   pails,   etc.,    924, 

927. 
Manhattan   Savings  Bank  fire,   129, 

522. 

Mansard  roofs,  672  *. 
Manual  boxes,  911,  921,  955,  956. 
"Manufacturers"      sprinkler      head, 

871  *. 
Marble,   action    of    under   fire,    218, 

521,  522,  635. 
destruction  of,  in  Baltimore 

fire,  159*. 
fire  tests  of,  218. 
Marbleite,  see  Sorel  Stone. 
Marbolith,  see  Sorel  Stone. 
Marlborough-Blenheim  Hotel,  Atlan- 
tic City,  627,  641. 

Maryland  Trust   Co.'s  Bldg.,  Balti- 
more fire,  170,  581  *,  582  *. 
Masonry,  permeability  of,  284. 
Matches,  30. 

Materials,  fire-resisting,  cost,     avail- 
ability, 210. 
definition  of,  207. 
efficiency  of,  208. 
limitations  of,  208. 
strength  of,  209. 
Mayer    Israel    Bldg.,   New    Orleans, 

659*. 

McClurg  Store,  Chicago,  459. 
Means  of  egress,  300,  717,  811. 
Merchants'     National    Bank,    Balti- 
more, 174. 

Metal  and  wire  glass  enclosures,  503, 
506  *,  507  *,  542,  543  *,  544  *. 
covered  trim,  413  *,  423,  483  *. 
furniture,  835. 

advantages  of,  836. 
use  of,  836. 

Metal  lath,  691  *,  692  *. 
Metal  lath  and  plaster  ceilings,  132. 
column  protec- 

tions,   349,    359, 
360*. 

conductivity  of ,  3  5  5. 
furring,  648,  689. 
partitions,        389  *, 
390*,  391*, 

392*,  393. 
residences,  767. 
wall     furring,    648, 

689. 
Metallic   doors,    483*,    484*,    485*, 

.498*. 
Metallic  fire  curtains,  724. 


Metal  lumber,  768,  769  *. 
Metal  trim,  413  *,  497  *,  498  *. 
Metropolitan  Life  Tower,  855. 
Metropolitan  Opera  House  fire,  132. 
Mill  construction,     advantages     and 

disadvantages  of,  798. 
approximate  cost  of,  100. 
belt,  stairway,  and  elevator 

towers,  80  *. 
cost    diagrams,    102  *,    103  *, 

104*. 

definition  of,  75. 
depreciation  of,  805. 
detail  of  C.  I.  wall  box  for  floor 

timbers,  83  *. 
floor   girder   on    wall 

plate,  83  *. 
post    and     roof    tim- 
bers, 89*. 
roof  at  division  wall, 

89*. 

roof    timber    on    col- 
umn cap,  84  *. 
roof    timber   on   wall 
4(  plate,  82  *. 
"saw-tooth"     roof 

valley,  97  *. 
typical     column    and . 
girder     connection, 
84*. 

dry  rot  in  timbers,  98,  799. 
factories,  69,  etc.,  798. 
floors,  77, 
four-story  storehouse,  84,  86  *, 

87*.  m 
ideal  mill  plant  layout  of  fire 

protection,  72,  73  *. 
limitations  of,  76. 
one-story  storehouse,  88  *. 
one-story  workshop,  90,  91  *. 
posts  or  columns  for,  79. 
requirements   of    Nat.  Bd.  of 

F.  U.,  98. 
"saw-tooth"   roofs,    92,    93*, 

95  *,  97  *. 
steel  girders,  78. 
typical  mill  building,  81  *. 
use  of,  69. 
vs.  concrete,  804. 
wrong  applications  of,  75. 
Mills  Building,   San   Francisco,  386, 

593. 
Milwaukee  Electric  Ry.  &  LightjCo.'s 

Bldg.,  569  *. 
Minneapolis  Lumber  Exchange   fire, 

131. 

Moisture  from  pipes,  291. 
Monadnock  Building,  Chicago,  375  *. 
"Monarch"  tile  block  columns,  378  *. 
Monolithic  floors,  259. 
Mortar-blocks,  conductivity  of,  254. 
fire  tests  of,  254. 
manufacture  of,  252. 
Mortars,  cement,  256. 

fire-resistance  of,  256. 

lime,  255. 

permeability    and    porosity 

of,  283. 
use  of,  255. 


INDEX 


1029 


Mozart  SchooirChicago,  750*.  751  *. 
Mullions,  450,  656. 
Municipal  Building,  N.  Y.,  856. 
"Mushroom"    system    of    reinforced 

concrete,  612. 

Music  Building,  Chicago,  414. 
Mutual  Fire  Ins.  Co.'s,  56. 
Mutual    Life    Bldg.,   San    Francisco, 

condition  of  steel  in,  274. 

N 

Naphtha,  839. 

"Natco"  column  construction,  379*. 
hollow    tile    blocks,    770*, 

771*. 
National  Board  Building  Code,  brick 

floor  arches,  325. 
garages,  815,  etc. 
limitation  of  areas,  308. 
shutters,  427. 
spandrel  walls,  652. 
window  protection,  421. 
National  Board  of  F.  U.,  committees 

9f,  50. 

objects  and  purposes,  50. 
standard      specifications, 

52,  54. 
National  Fire  Protection  Association, 

objects  and  membership,  52. 
National       Museum,       Washington, 

D.  C.,  328. 
"National"      standard      yard      hose 

houses,  981  *,  983  *. 
"National"  thermostats,  913. 
New  Jersey  factory  laws,  534. 
"Newman"      portable     watch-clock, 

948*,  949*. 

N.  Y.  Bldg.  Dept.  tests,  121. 
See  also  Tests, 
concrete,  243. 
concrete  floors,  613. 
kilns,  122  *. 
"New    York"     hollow 

tile  arches,  560. 
partitions,     387,     405, 

406,  408. 
present      requirements 

for,  123. 
terra-cotta  arches,  589, 

592. 

New  York  Hippodrome,  723. 
New    York    Life   Building,    Chicago, 

363  *. 
"New  York"   reinforced    terra-cotta 

arches,  559,  560*,  561*. 
Non-freezing  solutions  for  fire  pails, 
etc.,  927. 

O 

Office  buildings,  298. 

Oiling,  of  steel  work,  278. 

Oils,    etc.,    spontaneous    combustion 

of,  838. 
Oper  sprinklers,  cornice,  885  *. 

eave,  885  *. 

installation  of,    884. 

location  of,  886. 


Open  sprinklers,  orifices  of,  886. 

pipe  sizes  for,  887  *. 
ridge  pole,  885  *. 
risers       and       feed 

mains,  888. 
tests  of,  890. 
types  of  heads,  884, 

885*. 

use  of,  884,  891. 
valves,  888. 
water     supply     for, 

888. 
window     protection 

through,       425, 

885  *,  889. 


Pabst  Building,  N.  Y.,  284. 

Pacific    Mutual    Life    Building,   Los 

Angeles,  441. 

Pacific  States  Tel.  &  Tel.  Bldg.,  San 
Francisco,    353,    368*,    424,    439*. 
440*,  461,  466. 
Package  chutes,  547. 
Painting,  of  iron  and  steel,  277,  278, 

281. 

Paints,  fire-retarding,  938. 
Park  Row  Building,   322,  347,  502  *. 
Parker  Building  fire,  183,  349,  351*, 

853. 

Partitions,  conclusions,  416. 
concrete,  407. 
concrete-block,  408. 
Conroy  Bros.,  397. 
enclosing-stair-well,    502*, 

503  *,  505,  507  *. 
fire-resisting  trim  for,  411, 

412*. 

functions  of,  381. 
gypsinite     studding     for, 

409. 

gypsum,  394. 

hollow     metal     lath     and 

plaster,  389  *,  390  *. 

in  Baltimore  fire,  384. 

in  Granite    Building   fire, 

385  *. 

in  San  Francisco  fire,  386. 
interlocked,  396. 
"keystone"  plaster  blocks, 

395,  397. 

load-bearing,  388. 
metal-braced,  405. 
"Phoenix"  braced,  406. 
plaster  board,  408. 
plaster-block,  393,  396. 
plaster  of  Paris  and  cinder 

block,  395. 
"Prong-lock"     studs    for, 

390*. 

"Pyrobar"  block,  394. 
requirements  of,  382. 
sheathings  for,  408. 
solid      metal      lath      and 
plaster,  390,  391*,  392*. 
393. 

sound-proof,  414. 
stair  well,  etc.,  409,  541. 


1030 


INDEX 


Partitions,  steel  backs  for,  409. 

terra-cotta,      failures    of, 

385  *,  403. 

heights       and 

lengths,  399. 

setting  of,  400. 

sizes  of  blocks, 

398*,  399. 
tests    of,   401. 
weights        of, 

399. 
tests  of,  384,  387,  393,  396, 

397,  401,  405. 
thickness  of,  398. 
trim  for,  411,  412*. 
types  of,  384. 
wire  glass,  409. 
Party  walls,  660. 
Patent  plasters,  284. 
Paterson,   N.  J.,   conflagration,    150, 

663. 

Pemberton  Building,  Boston,  536  *. 
Pennsylvania  Railroad  Station,  N.  Y., 

446*. 

Pent  houses,  on  roofs,  675. 
Perforated    pipe    systems,    see  Base- 
ment Sprinklers. 
Perkins    Institution    for    the    Blind, 

stairs  in,  514  *. 
Permeability  of  fireproofing  materials, 

283. 
Philadelphia  tower  fire  escapes,  529  *, 

530*,  707. 

"Phoenix"  braced  partitions,  406. 
Pier  sheds,  306. 
Phelps    Publishing    Co.'s    Bldg.   fire, 

903. 

Pipe-  and  vent-shafts,  545. 
Pipe   spaces  in   column   protections, 

373,  375  *,  376  *. 
Piping,  moisture  from,  291. 
Pittsburgh  Athletic  Assn.  Bldg.,  658*. 
Planning,  see  Design. 
Plaster,  board,  257,  408. 

blocks,    257,    258,    393,    396, 

630. 
constructions,   fire-resistance 

of,  256. 
in    San    Fran- 
cisco    fire, 
256. 

of  Paris,  257. 
of  Paris  column  protections, 

350,  360. 

of  Paris,  conductivity  of,  355. 
of  Paris  partitions,  393,  396. 
Plate-iron  doors,  471,  491  *. 

shutters,  430,  432  *. 
"Poland  Spring  House,"  905. 
Porosity    of    fireproofing    materials, 

283. 

Portable    watch -clocks,    see    Watch- 
clocks. 

Powder,  storage  and  care  of,  843. 
Powder  (dry)  fire  extinguishers,  936. 
Pressed  brick,  223. 
Prinz    Regenten    Theatre,    Munich, 
Bavaria,  725  *. 


Prism   glass,    fire-resistance   of,    267, 

460. 

windows,  459. 

Private  fire  departments,  974. 
Produce  Exchange,  N.  Y.,  519  *. 
"Prong-lock"  partition  studs,  390*. 
Proscenium  walls,  see  Theatres. 
Protective     coatings    for    steelwork, 

281. 

Protective  qualities  of  cement,  279. 
Prudential     Life    Ins.     Co.'s     Bldg., 

Newark,  460. 
"Pyrobar"  partition  blocks,  394. 

Q 
Quick  emptying  tests  in  theatres,  704. 

R 

Raised     skewbacks     for     terra-cotta 

arches,  569*,  570*,  586*,  587*. 
Reconstruction,  after  fire,   205.   295, 

380,  621,  635. 
Refrigerating  rooms,  335. 
"Regan"  nozzles,  737*. 
Reinforced  concrete,  601. 

columns,       371, 

372*. 

design   of,    602. 
factories,       800, 

804. 

floors,  601, 
606  *,  607  *, 
608*,  612*, 
613. 

garages,  825. 
residences,    778. 
schools,  752. 

terra-cotta  columns,  379  * 
Residences,  basement  ceilings,  765. 
brick  and  stone,  779. 
brick  and  hollow  tile,  779, 

780*. 

causes  of  fires  in,  758. 
chimneys    and    flues    in, 

759,  760*,  761*. 
closets,  765. 
concrete,  776,  778. 
concrete     block,      777*, 

778*. 

costs  of,  787,  789. 
electric  wiring  in,  763. 
fire-extinguishing     appli- 
ances for,  785. 
fire  hazards  in,  757. 
fire-resisting,  766. 
fire-stopping,   763,   764  *, 

765*. 
heating     apparatus     in, 

763. 

hollow  tile,  769,  770*, 
771*,  772*,  773*, 
774  *,  775  *,  770  *, 
780*. 

interior  finish  for,  784. 
metal  casement  sash  for, 

786,  786*,  787*. 
metal   lath   and   plaster, 
767. 


INDEX 


1031 


Residences,  metal  lumber,  768,  769  *. 
"ribbed  concrete,"  781  *. 
roofs  for,  766,  775. 
shafts  in,  766. 
stairs  in,  765. 
stone,  781  *. 
stucco,  767. 
wall    finishes    for,    782  *, 

783*. 

wood  and  hollow  tile,  767. 
"Ribbed    concrete"    wall    construc- 
tion, 781  *. 

"Richardson  "  kalamine  doors,  482  *. 
Ring  Theatre  (Vienna)  fire,  698. 
Rise  and  tread  of  stairs,  511,  520,  717. 
Rodef  Sholem  Synagogue,  328. 
Rolling  steel  doors,   "Abacus,"  480, 

492*. 

double  automatic, 
491,492*,493*. 
tests  of,  480,  492. 
types  of,  476. 
"Wilson  Arrange- 
ment   No.    1," 
478*,  479*. 
shutters,  "Abacus  No. 
4,"  436,  437*, 
438*. 
automatic,      436, 

437*,  438*. 
in  San  Francisco 
conflagration, 
424. 

tests  of,  454. 
types    of,    435, 

436*. 
Roof  coverings,  664,  680.      See  also 

Roofs. 

framing,  protection  of,  669. 
nozzles,  966,  967  *. 
spaces,  669. 
surfaces,  670. 
trusses,  669,  671  *. 
Roofing  and  ceiling  blocks,  677,  678  *, 

679*. 

Roofing,  tile,  685. 

Roofs,  access  to,  from  fire  escapes,  539. 
asbestos  felt,  683. 
asbestos  roofing  shingles  for, 

686. 

brick,  681. 
ceiling  blocks  for,   677,   678  *, 

679. 

classification  of,  664. 
combined  with  ceilings,  665. 
composition,  683. 
concrete,  666  *,  668  *. 
coverings  for,  680. 
examples  of,  666  *,  668  *,  671*, 

672  *,  673  *. 
flat,  665,  681. 

"Ferroinclave,"  269*,  685. 
fire-curtains  for,  674. 
fire-resisting,  665. 
hollow    tile    blocks    for,    677, 

678*.  679*. 
importance  of,  663. 
mansard,  672  *. 
mill  construction,  82*.  84*.  89*. 


Roofs,  pent  houses  for,  675. 

pitched,  669,  684. 

protection  for  theatre,  738. 

residence,  766,  775,  776  *. 

requirements  for  fire-resisting, 
663. 

V saw-tooth,"  92,  93*,  95*, 
97*. 

scuttles  for,  676. 

semi-fire-resisting,  673. 

skylights  on,  676. 

slate  shingles,  684  *. 

slate  tile,  682. 

suspended  eeilings  under, 
668*,  686,  687*.  688*, 
689*. 

tile  for,  685. 

trusses  for,  669,  671  *. 

vitrified  tile  for,  682. 

wooden,  686. 

Rookery  Building,  Chicago,  460. 
Roosevelt  Building  fire,  152,  522. 
Rubber  stair  treads,  524. 
Ryerson  Building,  Chicago,  350. 


Sackett  plaster  board,  257,  408,  415. 
Safe  Deposit  and  Trust  Co.'s  Bldg., 

Baltimore,  435. 
Safe  loads  for  architectural  terra-cot- 

ta,  638. 

combination          terra- 
cotta   and    concrete 
floors,  628,  629. 
combination         terra- 
cotta arches,  566. 
end-construction  terra- 
cotta arches,  566. 
' '  Johnson ' '     long-span 

T.  C.  floors,  564. 
"Natco"    hollow    tile 

blocks,  771. 
segmental     terra-cotta 

arches,  574. 
side  construction  T.  C., 

arches,  555,  556. 
terra-cotta  walls,  641. 
Safes,  fire-resistance  of,  827. 
in  Baltimore  fire,  828. 
in  San  Francisco  fire,  828. 
Parker  Building  fire,  335. 
portable,  827. 
provisions  for,  334. 
weight  of,  334. 

Safety  fire  bucket  tank,  926  *. 
Safety  treads  for  stairs,  523,  717. 
"Saino  "  fire  doors,  476,  477  *.   « 

shutters,  433  *,  434  *. 
Salt,  927. 

Sand  and  deterrents,  823,  924,  932. 
Sandstone  under  fire  test,  218. 
San  Francisco  City  Hall,  636. 
San  Francisco  conflagration,      build- 
ings burned,  180. 
causes  of  building  fail- 
ures, 319. 

column      failures      in, 
348,  349,  352. 


1032 


INDEX 


San  Francisco  conflagration,  concrete 

in,  245,  620. 
deductions,  181. 
description  of,  178. 
face-brick  in,  224. 
fire  protection,  179. 
partitions  in,  386,  505. 
safes  in,  828. 
steel  frames  in,  213. 
suspended   ceilings  in, 

344,  687. 
terra-cotta     in,      238, 

593. 

vaults  in,  831. 
vertical    openings    in, 

540. 
wall    construction    in, 

634,  636. 

window  protection  in, 

423,  430,  431*,  432*, 

439*,    440*,    458*, 

459*.  462. 

wire  glass  windows  in, 

455,  458*. 
"Saw-tooth"    roofs,    92,    93*,    95*, 

97*. 
Schiller   Theatre   Building,    Chicago, 

fire  in,  640. 
Schools,  297,  740. 

assembly  halls,  750. 
conclusions,  756. 
concrete,  752. 
construction,  752. 
corridors,  exits,  etc.,  749. 
cost  of,  754. 
exit  doors,  749. 
fire  alarm  system,  752  *. 
fire  drills,  753. 
fire  escapes,  751. 
fire  hazard  in,  740. 
fire-resisting,  742. 
"first  aid"  appliances,  753. 
height  of,  743. 
location  of,  742. 
masonry  and  wood  joist,  741. 
planning  of,  743. 
stairs  in,  744,  747,  748  *. 
types  of,   741,    743*,    744*. 
745*,   746*,  749*,  750*, 
751*. 

wooden,  741. 
Scuppers,  337  *. 
Scuttles,  on  roofs,  676. 
Seats,  theatre,  714. 
Segmental  terra-cotta  arches,        cen- 
tering for,  579. 
' '  Haverstraw ' '      hollow 

brick,  570*. 
safe  loads  for,  574. 
side  construction,  571  *. 
short-span,  572  *. 
with  suspended  ceilings, 

572* 

Selection  of  concrete  floor,  620. 
floor  type,  345. 
hollow  tile  floor  type,  596. 
window  protection,  464. 
Self-supporting  vs.  veneer  walls,  634. 
Shafting  in  factories,  794,  795*. 


Shaft  openings,  645,  646  *,  766. 

Sheathings,  408. 

Sheet-iron  doors,  471,  490,  491  *. 

shutters,  430,  432  *. 
Sheet-metal  doors,  483  *,  484  *,  485  *. 
trim,  413  *,  498  *. 
windows,  442  *. 
Shelving,  metal  837. 
Shreve  Building,  San  Francisco,  353. 
Shutters,  corrugated-iron,  433  *,  434. 
in  Baltimore  conflagration, 

422. 

in  San  Francisco  conflagra- 
tion, 424,  431  *,  432  *. 
inside  folding,  434. 
Kinnear,   436,  437*,  438*. 
requisites  for  fire-resisting, 

427. 

"Saino"  fire,  433*.  434*. 
sheet-iron,  430,  432  *. 
steel-rolling,      435,      436  *, 
437  *,  438  *,  439  *,  440  *. 
tin-covered,  427,  431  *. 
types  of  fire-resisting,  426. 
underwriters',  426. 
vs.  wire  glass  windows,  460. 
Side-construction   terra-cotta  arches, 

see  Terra-cotta  Arches. 
Siegel  Store,  Boston,  891  *. 
Sills  for  fire  doors,  494,  495  *,  496  *. 
"Simplex"      watchman's      recorder, 

950*,  951  *. 
Singer  Building,  N.  Y.,  485,  856,  970, 

971*. 
Skylights,  on  roofs,  676. 

over  stage,  see  Theatres^ 
Slate   and   marble   treads   and   plat- 
forms, 521. 

Slate  roofs,  682,  684  *. 
Sodium  chloride,  927. 
Solid  vs.  hollow  column  casings,  357. 
Sorelite,  see  Sorel  Store. 
Sorellith,  see  Sorel  Stone. 
Sorel  stone,  tests  of,  259. 
use  of,  258. 

Sound-proof  partitions,  414. 
Spandrels,  650. 

concrete,  656. 

examples  of,  652  *,  653  *, 

654*,  655*. 
fire-resistance  of,  651. 
requirements  for,  651. 
"Special  Building  Signals,"  955. 
Special  hazards,  30,  298,  838,  932. 
Speculative  building,  320. 
Spontaneous  combustion,  838. 
Sprinkler     alarm     and     supervisory 

system,  909,  919. 

Sprinklers,  air-pressure  tanks  for,  876. 
alarm     valves     fbr,     877. 
879*,  880*,  881*,  920. 
allowances  for,  906. 
applicability  of,  866. 
automatic  dry-pipe,  881. 
wet-pipe,  863. 
basement,     891,    see    nho 

Basement  Sprinklers, 
check-     and    gate-valves, 
for,  877,  920. 


INDEX 


1033 


Sprinklers,  cornice,  885  *. 

corrosion  of  heads,  992. 
dry-pipe  vs.  wet-pipe,  882, 

899. 

early  application  of,  864. 
eave,  885  *. 
efficiency  of,  895. 
example   of   rebate   value 

of,  62. 

feed  mains,  873,  874  *. 
fire  pumps,  876. 
'  fusible  solder  for,  865. 
gravity  tanks  for,  875. 
heads,  871*,  872*. 
in  factories,  807,  811. 
inspection     and     mainte- 
nance of,  986,  996. 
in  theatres,  736. 
limitations  of,  904. 
location  of  heads,  869. 
maintenance  of,  986,  996. 
open,     425,     884,     885*, 
887*,  889,    891*.     See 
also  Open  Sprinklers, 
pipe  sizes,  873. 
principles  of,  863. 
requisites   for   protection, 

867. 

ridge-pole,  885  *. 
risers,  874. 

statistics  regarding,  897. 
steamer    connections    to, 

877. 
supervisory     service     for, 

909,  919,  920. 
types  of,  863. 
use  of,  866,  904. 

in  car  barns,  905. 
in  hotels,  904. 
water  supply  for,  875,  920. 
window,  885  *. 
St.  Francis  Hotel,  San  Francisco,  353, 

368. 

Stage,  see  Theatre. 
Stairs,  300,  302,  501,  717,  744. 

adjacent     to     elevator     well, 

503*,  541. 
capacity  of,  509. 
circular,  around  elevator,  502*. 
concrete,  526,  527  *,  528  *. 
design  of,  501. 
double,  718*,  748*. 
enclosing  partitions  for,    505, 

507*. 

emergency  access,  303. 
emergency  egress,  301. 
fire-escape,  see  Fire  Escapes, 
garage,  821. 
Guastavino,  525,  526  *. 
intermediate  platforms,  512. 
isolation  of,    504,    747,    748*, 

749*. 

location  of,  501,  509. 
marble  and  slate  treads,  521. 
metal  and  glass  enclosures  for, 

503  *,  506,  507  *. 
newel  posts  for,  519. 
ordinary  service,  301. 


Stairs,  partial    enclosures    for,     506, 

507  *. 

railings  for,  524. 
residence,  765. 
rise  and  tread,  511,  520. 
safety  of,  510,  521. 
safety  treads  for,  523,  717. 
school,  744,  747,  748*. 
soffits  of,  518. 
strength  of,  512. 
sub-treads  for,  522. 
supports  for,  508. 
terra-cotta,  525  *. 
theatre,  717,  718*. 
treads  and  landings,  521. 
types    of,    513,    514*,    515*, 
516*,    517*,    518*.    519*. 
718*. 

winders,  511. 
Standpipes,  automatic     valves     for, 

964. 

Boston    practice    regard- 
ing, 969. 
capacity  of,  960. 
check-valves  for,  962.. 
essentials     for     efficient 

service,  959. 
hose  for,  965. 
hose     racks    for,     963  *, 

964*. 
in     Equitable     Building 

fire,  973. 
in  factories,  807. 
in  Singer  Building,  N.  Y., 

970,  971  *. 

inspection    and    mainte- 
nance of,  998. 
location  of,  959. 
New     York     regulations 

regarding,  967,  968. 
roof  nozzles,  966,  967  *. 
water  supply,  961. 

Stationary  watch-clocks,  see  Watch- 
clocks. 

Steam  pipes,  763,  840,  841*,  842*. 
Steel,  bucks  for  partitions,  409. 
cleaning  of,  278. 
columns,  tests  of,  212. 
condition    of,     in    torn    down 

buildings,  273,  284. 
corrosion  of,  273. 
doors,  see  Doors, 
expansion  of,  211. 
factories,  799. 

necessity  for  protection  of,  211. 
oiling  of,  278. 
painting  of,  277,  278. 
protective  coatings  for,  281. 
reinforcement     for     concrete 

arches,  603,  604. 
shelving,  837. 
tonnage  of  structural,  in  U.  S., 

271. 

Steel  frames,  in  Baltimore  and  San 
Francisco  buildings,  212. 
protective  coatings  for, 

281. 

protective    qualities    of 
cement  on,  280. 


1034 


INDEX 


Steel-woven  oak  flooring,  341. 
Stones,      see      Granite,      Limestone, 

Marble,  Sandstone. 
Stoves,  763. 

Stucco  finish,  782  *,  783  *. 
garages,  825. 
residences,  767. 
Stuyvesant  High  School,  N.  Y.,  746, 

748*. 

Sub-division  of  large  areas,  305,  383. 
Suspended  ceilings,  efficiency  of,  343, 

687. 

in  San  Francisco 
buildings,    344, 
687. 
metal     lath     for, 

691*,  692*. 
roof  spaces  over, 

669. 
specifications  for, 

688. 

types  of,  572*, 
611*,  612*, 
668  *,  686, 

687*,        688*, 
689*. 
wire      clips     for, 

344*. 
T 
Temperatures,  exhibited  in  fires  and 

conflagrations,  192. 
Terra-cotta    and   concrete   floors,  see 

Combination  Floors. 
Terra-cotta  arches,    advantages   and 
disadvanta  g  e  s 
of,  599. 

beam  and  girder 
protections,  see 
Beam  Protec- 
tions, see  Gir- 
der P  r  o  t  e  c- 
tions. 

behavior  of  in 
actual  fires, 
593. 

camber  of,  577. 
ceiling  finish,  575. 
combination  con- 
struction,  565, 
566*,  568*. 
construction     of, 

551,  597. 
depth  of,  568,597. 
e  n  d-c  onstruc- 
tion,557,  558*. 
559*,  560*. 
floor  finish,   575. 
inspection  of,  5  79. 
insulated,  335. 
"Johnson     long- 
span,        562  *, 
563*. 

load     tests     and 
factor         of 
safety,   595. 
method     of    sot- 
ting, 576,  577*. 
raised  skewbacks 
for,  569*,  570*. 


Terra-cotta    arches,   safe    loads    for, 
555,    556,  564, 
567,  574. 
segmental,        see 
Segmental     T. 
C.  Arches, 
selection  of  type, 

596. 

side-c  o  n  s  t  r  u  c- 
tion,  551,552*, 
553*. 

strength  of  side- 

vs.    e  n  d-c  o  n- 

struction,  589. 

tie-rods  for,  333, 

575. 

tests  of,  see  Tests. 
vs.         concrete 
arches,  345. 
waterproofing 

of,  335. 

weather  a,nd  stain 

protection,  576. 

Terra-cotta,    architectural,    cornices. 

657. 

durability  of,  226. 
fire-resisting     proper- 
ties, 227. 

improvements  needed 

in  use  of,  227,  637. 

in  Baltimore  fire,  227, 

228. 
in  San  Francisco  fire, 

227,  228. 
manufacture  of,   225, 

637. 

setting  of,  638. 
spandrels,  650. 
strength  of,  638,  639. 
wall         construction, 

638,  639  *,  640  *., 
beam    protections,   580, 
581*,     582*,     583*, 
584*. 

ceiling  tile,  677,  678*. 
column  protections,  350, 
360,  361*,  362*.  363*, 
364*,      365*.      366*, 
372*. 

conclusions,  239. 
conductivity  of,  355. 
cornices,  657,  658*,  659*, 
fire-resisting  qualities  of, 

235. 
floors,     see    Terra-cotta 

Arches. 

furring  blocks,  648*. 
girder   protections,    580, 
584*,      585*,      586*, 
587*. 

hard-burned,         charac- 
teristics of,  234,  237. 
manufacture  of,  234. 
vs.  porous,  237. 
in  Baltimore  fire,  238. 
in    San    Francisco    fire, 

238. 

partitions,     failures     of, 
385  *,  403. 


INDEX 


1035 


Terra-cotta    partitions,   heights    and 
lengths, 
399. 
setting        of, 

400. 

sizes         of 

blocks, 

398*,  399. 

tests  of,  401. 

weights      of, 

399. 

permeability,       porosity 
and    chemical    action 
of,  285. 
porous,  characteristics 

of,  234,  237. 
method  of  man- 
ufacture, 229. 
vs.    hard-burned 

237. 
residences,     see    R  e  s  i  - 

dences. 

roofing  tile,  682. 
semi-porous,      manufac- 
ture of,  233. 
stairs,  525  *. 
structural,      for      walls, 

638,  639*,  640*. 
trim,  412  *. 
varieties  of,  229. 
vaults,  829  *. 
vs.  concrete,  235,  252. 
wall  furring,  648*. 
walls,   638,  639*,  640*. 
Terrazzo  floors,  341. 
Test-kilns,   N.   Y.   Building   Depart- 
ment, 122  *. 
Tests,  Associated     Factory     Mutual 

Laboratories,  121. 
blast-furnace    slag    concretes, 

619. 

British    F.  .P.    Com.,     "armo- 
crete"  floors,  617, 
618  *. 
' '  Coignet ' '    system 

floors,  617. 
combination    floor, 

631. 
"composite"  doors, 

474. 
concrete,  243. 

floors,  614. 
doors,  "armoured," 

470. 
asbestos-clad, 

473. 
plate-iron, 

471,  473. 
steel    rolling, 

480,  492. 
tin-clad,  470, 

471. 

fire      pails,      extin- 
guishers, etc. ,933. 
fire-retarding       so- 
lutions, 940. 
object  of,  114. 
partitions,  388,  402. 


Tests,  British  F.  P.  Com.,  petroleum 

products,  934. 
standards    of    fire- 
resistance,  115. 
terra-cotta    arches, 

591. 
tin-clad  doors,  470, 

471. 

windows,  451,  453. 
wire  glass,  451,  453. 
cast-iron  columns,  215. 
combination    terra-cotta    and 

concrete  floors,  631,  632. 
"Columbia  "  Fire  Testing  Sta- 
tion, 124,  592,  613. 
fire  and  water,  classified,  128, 

209. 

German,  125. 
Guastavino  floor  construction, 

592. 

manufacturers',  113. 
metal  furniture,  836. 
"Monarch"     tile     block     col- 
umns, 378  *. 
motar-blocks,  254. 
N.  Y.    Building    Department, 

121. 

concrete,    243, 

floors,    613. 

floors,  560,  589, 

592,  613. 
kilns,  122  *. 
partitions,  387, 
405,  406,  408 
present      re- 
quirem  e  n  1 3 
for,  123. 
terra-cotta 
arches,    589, 
592. 
partitions,  384,  387,  393,  396, 

397,  401,  405. 
reinforced    concrete    columns, 

371. 
reinforced  terra-cotta  columns, 

379*. 

steel  columns,  212. 
terra-cotta   arches,    588,    589, 

592. 
Underwriters'        Laboratories, 

Inc.,  119,  408,  409. 
U.  S.  Laboratories,  St.  Louis, 

117. 
Testing  Stations,  principal,  in  U.  S., 

113. 
Theatres,  697. 

aisles  in,  714. 

Austrian     experiments, 

721. 
automatic     sprinklers     in, 

736. 

Brooklyn,  fire  in,  698. 
construction  of,  738. 
costs  of,  73$. 
courts,  716. 
entrance  and  exit  doors  in, 

716. 

equipment  for,  736. 
escalators  in,  718. 


1036 


INDEX 


Theatres,  exits  in,  701,  706. 

fire    curtains,     721,     725*, 
726*,  727*,  728*,  729*. 
fire  drills  in,  738,  1014. 
fire  escapes,  719  *. 
"first  aids  "  in,  737. 
foyers  in,  715. 
inclines  and  ramps,  718. 
Iroquois,  153,  156  *. 
isolation  of  dangerous  risks 

in,  701. 

lighting  of,  718. 
lobbies,  715. 

location  and  site  of,  700. 
loss  of  life  in,  698. 
model     design     of,     708  *, 
709*,   710*.   711*,  712*, 

713*. 

passages  in,  715. 
planning  of,  699,  701,  708  *, 
709*.  710*,  711  *,  712* 
713*. 

proscenium  wall,  720,  736. 
protection     against     light- 
ning, 845. 

quick  emptying  of,  704. 
requisites  for  safety  in,  699. 
Ring,  Vienna,  698. 
roof  protection,  738. 
seats  in,  714. 
stage,  720,  735,  737. 
stairs  in,  717,  718*. 
standpipes  in,  737. 
statistics  of  fires  in,  697. 
tiers,  703. 
vents  over   stage   in,    731, 

732  *,  733  *. 
Thermostats,  "aero,"  915. 

allowances  for,  918. 
details   of,    913,    914  * 

915*,  917*. 
in  Baltimore  conflagra- 
tion, 917. 

installation  of,  911. 
j  ournal-bearing,       916, 

917*. 

location  of,  912. 
operation  of,  912. 
requisites  for,  912. 
types  of,  911,  912,914*. 

915*,  917*. 
"United  States,"  915  *. 
vapor,  916. 
"Watkins"     expansion 

spring,  914  *. 
Thickness  of  walls,  642. 
Tie-rods,  333,  575. 

protected,  575  *. 
Tin-covered  doors,    467,    468  *,    470 

489,  490*. 
shutters,  427,  431  *. 
Trap  doors,  489. 

Treads  and  landings  on  stairs,  521. 
Trim,  for  doors,  497  *. 

partitions,  etc.,  411,  412*, 

413  *,  498*. 

Turngemeinde    Club    House,    Phila., 
630. 


U 

Underwriters'      Laboratories,      Inc., 
building    of,     525  * 

563*. 

labeling  system,  120. 
organization  of,  119. 
roofing  specifications, 

681. 
Underwriters'  National  Electric  Assn., 

Union   Trust   Co.'s   Building,    Balti- 
more Fire,  169,  351  *,  581  *. 
United  States  Appraisers'  Stores  pro- 
posed, Boston,  610*. 
611  *. 

Appraisers'     Ware- 
house, N.   Y.  City, 
368  *,  438,  668  *. 
Assay     Office,    N.    Y., 

528  *,  609  *. 
Court  House  and  P.  O., 
Los  Angeles,  Cal., 
327*,  566*,  586*. 
606  *,  666  *,  672  * 
673*. 

Geological  Survey  tests 
of  concrete,  244. 
mortar-b  locks, 

254. 

partitions,  402. 
Laboratories      at      St. 

Louis,  117. 
Mint,    San    Francisco, 

424,  435. 
Post    Office,    Chicago, 

365*. 

P.     O.     and     Custom 
House,  Richmond, 
Va.,  606  *, 
612*. 

San  Fran- 
cisco, 410, 
666*. 

S  po  k  ane, 
Wash.  , 
369*,  607. 
611*. 

Printing  Office,  Wash- 
ington,  D.   C.,   325, 
326*,  369*. 
Public  Buildings,    117. 
Public     Stores     Bldg., 
after  Baltimore  Fire, 
217*. 
Thermostats,  913,915*. 


Valves,  automatic,  964. 

check-  and  gate-,  877,  962. 

inspection   and   maintenance 

of,  988. 

Vanderbilt  Building  fire,  142,  422. 
Vapor  thermostats,  916. 
Vault  doors,  832,  833. 
Vaults,  doors  for,  832,  833. 

in  Baltimore  fire,  830. 

in  Equitable  Building  fire,  834. 


INDEX 


1037 


Vaults,  in  San  Francisco  fire,  831. 
large,  833. 

proper  construction  of,  832. 
usual  inefficient  construction 

of,  829  *. 

Veneer  walls,  284,  633,  634,  643. 
Vents  over  stage,  see  Theatres. 
Vertical  openings,  design  of,  312. 

elevator       enclos- 
ures, 499,  540. 
in  residences,  766. 
rating  for,  in  typi- 
cal building,  67. 
stair  wells,  504. 
"Voigtmann"  fusible  links,  488*,  489*. 

W 

Waggoner    "Sanatory"    fire    bucket, 

926*. 

Waldorf-Astoria  Hotel,  347. 
Wall,  columns,  660,  661  *,  662  *. 
exposures,  420. 
finishes,  205,  649. 
mullions,  656. 
pocket  for  doors,  490  *. 
spandrels,     650,     652  *,     653  *, 

654  *,  655  *. 

Walls,  anchorage  of,  644. 
bearing,  633,  643. 
brick,  637. 
combination  tile  and  concrete, 

642. 

concrete,  641,  656. 
concrete-block,  642. 
court,  655. 
curtain,  633,  656. 
finish  of,  205,  649. 
fire,  643,  660. 
fire-resistance  of,  634,  643. 
furring  of,  647,  648  *,  689. 
hollow  concrete,  642. 
improper  enclosing,  507. 
iron  work  in,  507,  635. 
load-supporting,  633. 
materials  used  in,  635. 
mullions  in,  656. 
"Natco"    hollow    tile    blocks, 

771  *. 

openings  in,  645. 
ornamental  terra-cotta  in,  637. 
party,  660. 

residence,  see  Residences, 
self-supporting,  633,  634,  643. 
solid    enclosure,    for    elevator 

wells,  541. 
spandrel,     650,     652*,     653*, 

654  *,  655  *. 
stone,  160*,  635. 
terra-cotta,  638,   639  *,  640  *, 

641. 
terra-cotta   cornices   for,    657, 

658  *,  659  *. 

thickness  of,  642,  652,  656. 
types  of,  633. 
veneer,  633,  634,  643. 
Wanamaker  Bldg.,  Phila.,  658  *. 
Wanamaker     store,    N.    Y.,    568  *, 
587*. 


War  College  Building,  Washington, 

D.  C.,  630,  631  *. 
Warehouses,  design  of,  298. 

mill     construction,     see 

Mill  Construction, 
sub-division      of      large 

areas,  306. 

Waste  of  structural  materials,  21. 
Waste-paper  chutes,  546  *. 
Watch-clocks,  allowances  for,  957. 

central  station,  super- 
vision of,  953. 
dial  records  of,   949  *, 

951*. 
key    boxes    for,     948, 

949*. 

keys  for,  949. 
magneto,  950*. 
"Newman"    portable, 

948  *. 

portable,  947,  948  *. 
recorders  for,  952  *. 
"Simplex"         station- 
ary, 950  *. 

stations  for,  948,  949  *. 
stationary,  950  *. 
Watchmen,  944, 

allowances  for,  957. 
central      station      super- 
vision of,  953. 
efficiency  of,  909,  944. 
requirements  for,  945. 
service,  946. 
supervision  of,  947. 
Water  casks,  926,  927. 

freezing  of,  in  sprinkler  pipes, 

990. 

pails,  922,  926,  *,  933. 
pressure,  testing  of,  991. 
supply  for  standpipes,  961. 
supply  for  sprinklers,  875,  888, 

898,  987,  991. 

Waterproofing,  floors,  335,  794. 
scuppers,  337  *. 

"Watkins"  thermostats,  913,  914  *. 
Weights,  book  tile  and  roofing  blocks, 

678,  679. 

ceiling  blocks,  679. 
cement  floors,  330. 
cinder  concrete,  330. 
combination  terra-cotta  and 
concrete  floors,  628,  629. 
concrete  floor  slabs,  603. 
end-construction        terra- 

cotta  arches,  558. 
"Excelsior"      terra-cotta 

arches,  568. 
hollow  brick,  647. 
live  loads  on  floors,  331. 
marble  floors,  330. 
metal  lath,  692,  693. 
"New    York"     terra-cotta 

arches,  561. 

plaster  on  tile  arches,  330. 
safes,  334. 
side-construction       terra- 

cotta  arches,  554. 
wood  flooring,  330. 


1038 


INDEX 


Wells-Fargo  Building,  San  Francisco, 

459*. 
Western  Electric  Co.'s  Bldg.,  Chicago, 

572*. 
Western  Electric  Co.'s  Building,  Sari 

Francisco,  424,  455,  456  *,  458  *. 
West  St.  Building,  N.  Y.,  543  *,  544  *. 
Wet-pipe  vs.  dry-pipe  sprinklers,  882, 

899. 
Wilson  steel  rolling  doors,  477,  478  *, 

479*.  491,  493*. 

Windows,  automatically  closing,  449*. 
double-glazed,    4'52,    453*. 
drawn-bronze,    447,    448  *. 
factory,  792,  793  *. 
fire-tests  of,  451,  453. 
hollow  sheet-metal,  442. 
in  Baltimore  conflagration, 

422. 

in  San  Francisco  conflagra- 
tion, 423. 
kalamine,  444  *. 
mullioned,  450. 
open    sprinklers    for,    425, 
884,  885*,  887*,  891  *. 
prism  glass,  459. 
protection    of,     418,     461, 

464,  889. 

protection  rods  for,  545. 
rolled  steel,  793  *. 
shutters  vs.  wire  glass,  460. 
types  of  fire-resisting,  441. 
types    of    protection    for, 

425. 

wire  glass  in,  450,  460. 
wrought-     and     cast-iron, 
445,  446  *. 


Windows  vs.  shutters,  460. 

Wire  glass,  elevator  enclosures,  542*, 

543*,  544*. 
fire-resistance     of,    266, 

453,  455,  542. 
in  fire-resisting  partitions, 

414. 

kinds  and  sizes,  265*. 
manufacture  of,  264. 
partitions,  409. 
stair     enclosures,     503*, 

506,  507*. 
strength  of,  266. 
tests  of,    451,  453,   455, 

458*. 
windows,  443,  450,  455, 

460,  535, 
Wisconsin  Central  Ry.  Co.'s  Freight 

House,  Chicago,  640. 
Wood,  fireproof,   fire-resisting  quali- 
ties of ,  261. 
method    of    manu- 
facture, 260. 
use  of,  260. 
Wood  floors,  340, 

steel- woven  oak,  341. 
"Woodman"  thermostats,  913. 
Wool,    spontaneous    combustion    in, 

839. 
Woolworth  Building,  N.  Y.,  856. 

X 

X-tile  end-construction  arches,  559  *  « 


ALPHABETICAL   INDEX    TO   ADVERTISEMENTS 

PAGE 

AMERICAN  MASON  SAFETY  TREAD  Co 1 

ATLANTIC  TERRA  COTTA  Co 1 

BERGER  MFG.  Co 2 

DAHLSTROM  METALLIC  DOOR  Co 3 

EASTERN  EXPANDED  METAL  Co 2 

ESTY  SPRINKLER  Co 4 

FULLER,  GEORGE  A.,  COMPANY 4 

GAMEWELL  FIRE  ALARM  TELEGRAPH  Co 6 

GENERAL  FIRE  EXTINGUISHER  Co 5 

GUASTAVINO,  R.  Co 6 

KINNEAR  MANUFACTURING  Co 7 

MOSLER  SAFE  Co 8 

NATIONAL  FIRE  PROOFING  Co 9 

NEWMAN  CLOCK  Co 8 

PENNSYLVANIA  WIRE  GLASS  Co 10 

POMEROY,  S.  H.  Co 10 

TOCH  BROTHERS 11 

WILEY  &  SONS,  JOHN 11 

WILSON,  JAS.  G.  MFG.  Co 12 

WOOD-MOSAIC  Co 13 


CLASSIFIED   LIST  OF   ADVERTISEMENTS 

ARCHITECTURAL  TERRA  COTTA.  PAGE 

Atlantic  Terra  Cotta  Company 1 

AUTOMATIC  SPRINKLERS. 

Esty  Sprinkler  Co 4 

General  Fire  Extinguisher  Co 5 

BUILDING  CONSTRUCTION. 

George  A.  Fuller  Co. .  . 4 

EXPANDED  METAL,"  FURRING,  REINFORCING  MATERIALS,  ETC. 

Eastern  Expanded  Metal  Co 2 

FIRE  ALARMS  AND  SIGNALING  SYSTEMS. 

Garnewell  Fire  Alarm  Telegraph  Co 6 

METALLIC  DOORS  AND  TRIM. 

Dahlstrom  Metallic  Door  Co 3 

METAL  LUMBER,  METAL  LATH,  ETC. 

Berger  Mfg.  Co 2 

PAINTS  AND  PROTECTIVE  COATINGS  FOR  STEELWORK. 

Toch  Brothers 11 

ROLLING  STEEL  FIRE  DOORS,  SHUTTERS,  ETC. 

Kinnear  Manufacturing  Co 7 

Jas.  G.  Wilson  Mfg.  Co 12 

SAFES,  VAULT  DOORS  AND  BANK  VAULTS. 

Mosler  Safe  Co 8 

SAFETY  TREADS  AND  FIREPROOF  SANITARY  FLOORING. 

American  Mason  Safety  Tread  Co 1 

STEEL  WOVEN  FLOORING. 

Wood-Mosaic  Co 13 

TERRA  COTTA  HOLLOW  TILE  CONSTRUCTION. 

National  Fire  Proofing  Co 9 

TIMBREL  VAULT  CONSTRUCTION. 

R.  Guastavino  Co 6 

WATCHMEN'S  CLOCKS. 

Newman  Clock  Co 8 

WINDOWS,  FIRE-RESISTING. 

S.  H.  Pomeroy  Co 10 

WIRE  GLASS. 

Pennsylvania  Wire  Glass  Co 10 

iii 


SAFETY  TREADS 

AND 

FIREPROOF  SANITARY  FLOORING 

MASON  SAFETY  TREAD:  consists  of  a  base  of  rolled  steel  or  hard 
brass  with  ribs  inclined  to  each  other  in  pairs,  and  strips  of  lead  rolled  into 
the  dove-tailed  grooves  which  furnish  a  fire-proof  prevention  from  slipping. 


CARBORUNDUM  SAFETY  TREAD:  consists  of  Mason  steel  or 
hard  brass  base  with  the  grooves  filled  with  granulated  carborundum 
bound  by  cement. 

MASON   SAFETY    SIDEWALK  AND  VAULT  LIGHTS. 

KARBOLITH  makes  the  best  fire-proof ,  magnesite  flooring,  cove  base 
and  wainscoting  for  all  kinds  of  inside  construction.  Thoroughly  sanitary, 
noiseless,  elastic  and  durable. 

Catalogues  and  estimates  furnished  on  application  to 

American  Mason  Safety  Tread  Co. 

702  Old  South  Building  Boston,  Mass. 

Branches  at  New  York,  Philadelphia,  Washington,  Chicago,  St.  Louis 
and  Kansas  City.  Agencies  in  all  the  large  cities. 


The  Building  Material 

that  is 

Unaffected   by  Fire 

Atlantic  Architectural  Terra  Cotta  is  more  than  fire- 
proof. A  spreading  fire  may  pass  over  a  building,  melting 
a  metal  roof  and  gutting  the  interior;  but  if  the  exterior 
walls  are  of  Atlantic  Architectural  Terra  Cotta,  properly 
protected  on  the  inside  by  fire-proofing,  the  frame  will  be 
uninjured. 

Atlantic  Terra  Cotta  offers  an  exceptional  field  for  arch- 
itectural treatment  in  modeled  ornament  and  color.  Per- 
manently durable,  it  is  the  one  material  that  combines 
structural  efficiency  and  architectural  beauty  with  practical 
economy. 

Atlantic  Terra  Cotta  Company 

1 1 70  Broadway,  New  York  Booklets,  etc. 


The  logical  material  to  take  the  place  of  wood 
lumber  (structural  members)  Metal  Joists  and 
Studs  in  floor  and  partition  construction.  It 
assures  an  absolutely  non-combustible  and  in- 
destructible building  at  practically  the  same 
cost  as  wood  lumber. 
Address  nearest  branch  for  complete  catalogue. 

The  Berger  Mfg.  Co.,  canton,  Ohio. 

New  York  Philadelphia  Boston          Minneapolis 

San  Francisco       St.  Louis       Chicago       Atlanta 


Eastern  Expanded  Metal  Co. 

MANUFACTURERS  OF 

EXPANDED    METAL 

FIRE    DOORS,    FRAMES     AND 
FITTINGS 

REINFORCING   MATERIALS 

CONTRACTORS    FOR 

IRON  FURRING  AND  METAL  LATHING 


201    DEVONSHIRE  STREET 


BOSTON 


It  is  now  possible  to  obtain  absolute 

Interior  Fire  protection— the  Kind 

that   Safeguards  Life  and 

Contents 

Tenant,  owner,  builder  and  architect  should 
first  know  what  constitutes  absolute  fire -proof 
protection  rather  than  to  learn  after  a  fire 
has  occurred  that  their  confidence  had  been 
misplaced;  that,  however  perfect  and  fire- 
proof the  exterior  walls,  they  only  form  a 
flue  for  the  destruction  of  the  inflammable 
interior  and  contents  of  the  building. 

V\/rHEN  you  have  eliminated  all  inflammable  materials 
in    a    building   by    replacing  wood  with  steel  in 
every  part  of  its  interior,  then,  and  then  only  have  you  a 
fireproof  building  in  reality. 

Without  the  slightest  sacrifice  of  artistic  value,  with  higher 
first  cost  more  than  compensated  for  by  reduced  cost  of 
insurance  and  maintenance,  hundreds  of  representative  build- 
ings have  been  fireproofed  in  the  highest  sense  of  the  term  by 

DAHLSTROM 

Metallic  Doors  and  Trim 

Absolute  fireproofing  simply  means  that  wherever  wood  has 
heretofore  b^een  used  it  is  replaced  with  the  Dahlstrom  Steel 
Products.  If  the  exterior  walls,  floors  and  partitions  are  of 
fireproof  construction  and  the  last  link  in  the  chain,  the 
Dahlstrom  Metal  Doors  and  Windows  are  added,  every  room  is 
converted  into  a  fireproof  unit — artistic,  sanitary,  immune  from 
the  spreading  of  flames  for  all  time. 

Everycrne  who  values  human  life  should  draw  the  line  of 
distinction  between  so-called  "fireproof"  buildings  and  those 
fireproof  in  fact. 

To  the  interested  descriptive 
booklets  are  sent  free 

DAHLSTROM    METALLIC    BOOK    CO. 

Executive  Offices  and  Factories: 
18  Blackstone  Avenue,  Jamestown,  N.  Y. 

Branch    Offices    in    All    Principal    Cities 
3 


(two-thirds  size) 
MANUFACTURED  BY 

ESTY  SPRINKLER  GO. 

Laconia,  N.  H. 


GEORGE  A.  FULLER  COMPANY 

jPutlbtng  Construction 

Board  of  Trade  Building     ::     Boston 


NEW  YORK  CHICAGO  WASHINGTON 

KANSAS  CITY  PHILADELPHIA 

BALTIMORE  CANADA 


RINNELI 


AUTOMATIC  SPRINKLERS 


have  successfully  handled  more  fires 
than  all  other  Automatic  Sprinklers 
combined.  They  have  been  installed 
in  more  than  100,000  buildings.  They 
furnish  at  once  the  simplest,  the  most 
sensitive,  and  the  most  reliable  and 
complete  fire  protection  to  any  building 
or  its  contents. 


General  Fire  Extinguisher  Co. 

Executive  Offices  ::   Providence,  R.I. 

Plants,  Warehouses   and    Offices    in    Principal    Cities    of 
United  States  and    Canada 


40—40 


THE 


Gamewell  Fire  Alarm  Telegraph  Co. 


Manufacturers  and  Installers  of  approved  Fire  Alarm 
and  other  Emergency  Signaling  Systems 
for  Buildings,  Factories  and  Institu- 
tions of  all  kinds. 

Our  system  is  installed  in  over  6,000  private 
plants  and  Institutions. 

EXECUTIVE    OFFICES: 

30  Vesey  Street,   New  York,   N.   Y. 


NEW  YORK  BOSTON 

R.  GUASTAVINO  GO. 
Timbrel  Vault  Construction 

Contractors  for  the  erection 
of  all  masonry  floor  spans 
for  heavy  loads.  Big  roof 
domes  and  all  forms  of 
Cohesive  arches  in  rough  or 
finished  tile. 


Steel    Rolling 
Fire     Doors     and    Shutters 


Abacus  No.  i 

ABACUS  NO.  1  for  Elevator  Openings 

ABACUS  NO.  2  for  Elevator  Openings 

ABACUS  NO.  4  for  Exterior  Openings 
ABACUS  NO.  3  for  Fire  Walls 
Ajax  Sliding  Door  for  Fire  Walls 

Inspected  and  labeled  under  the  supervision  of  the  Under- 
writers' Laboratories  Inc. 

See  approved  list  issued  by  the  National  Board  of  Fire 
Underwriters. 

The  Kinnear  Manufacturing  Company 

COLUMBUS,  OHIO,  U.  S.  A. 


THE  MOSLER  SAFE  CO. 

MANUFACTURERS 

House,  Office,  and  Bank  Safes 
Safe  Deposit  and  Bank  Vaults 

51  SUDBURY  STREET,  BOSTON 
GEO.  E.  FOSTER,   New  England  Manager 


ABSOLUTE  SECURITY  is  SECURED 

BY  USING  THE 

Newman  Watchman's  Clock  System 

"A  Positive  Check  on  Human  Fallibility" 
SAFEGUARDS  THE 

Underwriters'  Laboratories— Chicago 

The  most  important  insurance  building  in  the  Country 


NEWMAN  CLOCK  COMPANY 

1526  Wabash  Ave.  178  Fulton  Street, 

CHICAGO  NEW  YORK  CITY 

Foreign  Representatives 

THE  NEWMAN  CLOCK  COY.,  Ltd. 

2  &  4  Whitechapel  Road,  London,  England. 


NATIONAL 

FIRE  PROOFING 

COMPANY 

ORGANIZED  1889 
MANUFACTURERS   OF 

TERRA  GOTTA 
HOLLOW  TILE 

CONTRACTORS    FOR 

FIREPROOF 
CONSTRUCTION 

MAIN   OFFICE: 

Fulton  Building  Pittsburgh,  Pa. 

CHICAGO :   Commercial  National  Bank  Building 
CINCINNATI:   Union  Trust  Building 

CANTON :   City  National  Bank  Building 
DETROIT :   Penobscot  Building 

MINNEAPOLIS :  Lumber  Exchange 

LOS  ANGELES:   Central  Building 

COLUMBUS :  West  Broad  Street 
NEW  YORK:    Flatiron  Building 

PHILADELPHIA:   Land  Title  Building 
BOSTON:   John  Hancock  Building 

WASHINGTON:  Colorado  Building 

CLEVELAND :  Chamber  of  Commerce  Building 
TORONTO:    Ontario 

MONTREAL:   Quebec     ' 

26  Factories  in  the  United  States 


FOR  FIRE  PROTECTION  SPECIFY 

SOLID  WIRE  GLASS  MADE  BY  THE    CONTINUOUS  PROCESS 

To  immediate  and  permanent  advantage.  It  possesses  greater  strength 
than  any  other  make,  and  when  properly  glazed  stands  against  fire  and  weather. 

For  Glazing  Light  Openings  in  Outside  Walls  where  same  are  subject 
to  attack  by  fire  from  within  or  without. 

For  Glazing  All  Skylights,  unless  it  is  desirable  that  same  shall  be  broken 
by  excessive  heat  for  purpose  of  outlet  for  smoke  or  flame. 

For  Glazing  All  Light  Openings  In  All  Interior  Fire-Retarding  Doors, 
Partitions,  and  other  cut-offs,  especially  in  Elevator  and  Stair  Enclosures. 


gth- 
unequalled  by  any  other  make. 

Our  new  pattern,  "Cobweb" 
\Vire  Glass,  possesses  remarkable 
diffusive  quality  and  extraordi- 
nary tensile  strength.  We  guar- 
antee it  against  breakage  in 
transit  and  installation  for  one 
year. 


PENNSYLVANIA  BUILDING 
PHILADELPHIA 


100  BROADWAY,  NEW  YORK 


Increases 

Rent 

Values 

Fire  Barriers 
Affording  Light 
and  Ventilation 

Decreases 

Fire 

Premiums 


The  Voigtmann  Standard  Automatic 

Closing  and  Locking  Windows 

a    Specialty 


The  Voigtmann  Adjustable  Weather 

Guide  Windows.     Interior  View 

Showing  Sash  Weights 


S.  H.  POMEROY  CO., 


INC. 


Successors    to     VOIGTMANN     &    CO.     OF     NEW  YORK 

Manufacturers  of  their  Specialties  under  Patents  in 

METALLIC     WINDOW     FRAMES     AND    SASHES 

FOR  CARRYING  WIRE  AND  PLATE  GLASS 
Tested  and  Approved  by  the  National  Board  of  Fire  Underwriters'  Laboratories 

FACTORY  AND  OFFICE 
430  WEST    14th  STREET  427  WEST  13th  STREET 

Tel.  771  Chelsea  NEW  YORK 

10 


DAMP    RESISTING    PAINT 

"TOCKOLITH."    (Pat'd)  A  cement  paini   for  priming  metal. 
Absolutely  prevents  corrosion. 

No.   110  "R.  I.  W."     Acid,  alkali  and  water  proof.      Prevents 
electrolytic  corrosion  of  metal. 

No.   112  "R»  I.  W."      A    finishing    coat    for    structural    steel. 
Prevents  corrosion. 

"R.  I.  W."   Smoke  Stack  Paint.      For  ail  hot  surfaces.     Stands 
heat  up  to  the  point  of  carbonization. 

Write  for   "  The  Red  Book"   for   detailed   information   concerning 
protective  coatings  and  specialties 

TOGH  BROTHERS  Estrd 

MANUFACTURERS  OF 

TECHNICAL  AND  SCIENTIFIC  PAINTS 

320  FIFTH  AVE.,  NEW  YORK 

Works  :   LONG  ISLAND  CITY,  N.  Y.,     TORONTO,     CANADA 

BOOKS    FOR    ARCHITECTS 

ARCHITECTURAL  ENGINEERING.  With  Especial  Reference  to  High  Build- 
ing Construction,  including  Many  Examples  of  Prominent  Office  Buildings. 
By  Joseph  Kendall  Freitag,  B.S.,  C.E.,  Associate  Member  American 
Society  of  Civil  Engineers.  Second  Edition,  Rewritten.  8vo,  xiv  +  40/ 
pages,  196  figures,  including  half-tones.  Cloth,  $3.50  (15,'-  net). 

THE  ORIENTATION    OF    BUILDINGS    OR    PLANNING    FOR    SUNLIGHT. 

By  William  Atkinson,  Fellow  of  Boston  Society  of  Architects.      8vo,  xiii  -\- 
139  pages,   74  figures.      Cloth,    $2.00  net  (8,6  net) 

PRACTICAL  METHODS  OF  SEWAGE  DISPOSAL.  For  Residences,  Hotels 
and  Institutions.  By  Henry  N.  Ogden,  M.  Am.  Soc.  C.E. ,  Professor 
of  Sanitary  Engineering,  Cornell  University,  and  H.  Burdett  Cleveland, 
Assoc.  M.  Am.  Soc.  C.E.,  Principal  Assistant  Engineer,  New  York  State 
Department  of  Health.  8vo,  vi+i32  pages,  52  figures.  Cloth,  $1.50  net 
(6/6  net) 

BUILDING  STONES  AND  CLAYS:  Their  Origin,  Characters  and  Examination. 
By  Edwin  C.  Eckel,  C.E.,  Associate,  American  Society  of  Civil  Engineers, 
Member,  Society  of  Chemical  Industry,  Fellow,  Geological  Society  of 
America.  8vo,  xiv  +  264  pages,  37  figures.  Cloth,  $3.00  net  (12  6  net). 

BUILDING  STONES  AND  CLAY  PRODUCTS.  By  Heinrich  Ries,  Professor 
of  Economic  Geology,  in  Cornell  University  (In  Press). 

INSPECTION  OF  THE  MATERIALS  AND  WORKMANSHIP  EMPLOYED  IN 
CONSTRUCTION.  Third  Edition,  Thoroughly  Revised.  By  Austin  T. 
Byrne,  Civil  Engineer,  Author  of  "Highway  Construction."  i6mo, 
xvi +  609  pages.  Cloth,  $3.00  (12, "6  net). 

JOHN    WILEY    &    SONS 

43  East  Nineteenth  St.,  New  York 
London:   CHAPMAN   &   HALL,    Limited 

11 


ROLLING  STEEL  FIRE  DOORS 

ROLLING  STEEL  DOORS  FOR  FIRE 
PROTECTION  AND  FOR  ENCLOS- 
ING ROUND  HOUSES,  FREIGHT 
SHEDS,  STORE  FRONTS,  CAR 
BARNS,  ELEVATOR 
OPENINGS,  ETC. 


GUN  SHEDS,  FORT  ETHAN  ALLEN,  EQUIPPED  WITH  WILSON'S 
INTERLOCKING  STEEL  DOORS 


MANUFACTURED   BY 

JAS.  G.  WILSON  MFG.  CO. 

3   AND  5  WEST   29TH    STREET 

NEW  YORK 


12 


A  real  Parquetry  Floor  for  the  building  of  Fireproof  Construction.  No 
flooring  but  a  wood  floor  is  ever  comfortable  to  walk  upon.  A  fine  office 
or  residence  that  has  not  Hardwood  Floors  is  a  cold  proposition. 

Steel  Woven  Flooring  has  stood  the  test  of  years  in  St.  Luke's  Hospital. 
The  floor  in  the  Baltimore  Bar  Library  was  flooded  for  forty-eight  hours 
during  the  great  fire,  as  it  was  from  this  room  of  the  Co.urt  House  that  the 
successful  stand  of  the  firefighters  was  made.  After  refinishing,  the  floor 
was  as  good  as  the  day  it  was  laid.  Several  carloads  were  laid  in  New 
York  Custom  House. 


Showing  two  border  and  wall  strips  with  bridge  over  compression  space  and 
short  dovetailed  pieces  of  wood  to  which  border  strips  are  llghty  nailed. 


No  big  beams  are  inserted  in 
the  concrete.  No  sticking  of 
blocks  to  concrete  which  will 
swell  and  tear  loose  with  change 
of  season.  The  floor  lies  solidly 
of  its  own  weight.  In  case  of 
swelling,  owing  to  dampness,  or 
even  flooding  with  water,  the  floor 
swells  as  a  whole  and  takes  up 
the  compression  space  in  the 
border.  If  the  floor  shrinks  again 


Detail  of 
4"  quartered 
white  oak  block. 


after  such  an  accident  the 
blocks  shrink  individually 
and  the  shrinkage  is  divided 
up  so  many  times  that  no 
cracks  are  seen.  In  extreme 
cases  the  entire  floor  can  be 
keyed  up  from  the  com- 
pression spaces. 


Please  send  for  our  literature 


four  blocks 
showing  steel  weave. 


WOOD-MOSAIC  CO. 

Rochester,  N.  Y.  New  Albany,  Ind. 


13 


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This  book  is  due  on  the  last  date  stamped  below,  or 

on  the  date  to  which  renewed. 
Renewed  books  are  subject  to  immediate  recall. 


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LD  21-32m-3,'74 
(R7057slO)476 — A-32 


General  Library 

University  of  California 

Berkeley 


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GENERAL  LIBRARY  -  U.C.  BERKELEY 


